20.04.2018

There is a huge amount of material on the Web about skin cancer. Unfortunately, information that is not presented in the form of scientific articles and not on the websites of dermato-oncologists does not stand up to scrutiny.

In this article, I will answer many burning questions: “how to recognize skin cancer in yourself?”, “is skin cancer dangerous?”, “what are the treatment options for skin cancer?” other.

Types of skin cancer

There are 3 types of common skin cancers. They differ both in the incidence rate (i.e., the chance of getting sick) and in the degree of danger to life - basalioma, squamous cell carcinoma and melanoma.

Melanoma- one of the rare and dangerous skin tumors. It is only 4% of total malignant skin tumors, but is the cause of almost 80% of deaths in this localization. Read more about melanoma.

Basal cell skin cancer

Basalioma- the most common, but at the same time the safest type of skin cancer. Death from basalioma is possible only in very advanced cases or with aggressive forms (basal squamous) tumors. The favorable course of basalioma is due to the fact that it almost never metastasizes (only 0.5% of cases).

Symptoms and signs

Most often, basalioma occurs on the skin of the nose, a little less often on the face, and much less often on other parts of the body.

The peak incidence occurs at the age of over 40 years. The youngest patient who was diagnosed with basalioma by histology was 39 years old.

What basal cell skin cancer looks like depends on the form:

1. Nodal shape (synonymous with nodular). The tumor is presented in the form of a nodule. It can be distinguished from other skin formations by an increased number of vessels on the surface, a waxy sheen and small gray-blue inclusions. All these signs are visible in the photo.

In addition, on the surface of the nodular basalioma there may be another feature- ulceration.

1. surface form basalioma in most cases is presented in the form of an area of ​​redness on the skin. Peeling elements and the waxy sheen already mentioned above are also possible.

1. Scleroderma-like form basalioma is very rare and often presents difficulties in diagnosis. It is characterized by a lighter and firmer seal compared to the surrounding skin.

1. pigment form basalioma is very a small part of the total number of these tumors. It is distinguished by a large amount of pigment. In this regard, basalioma is often mistaken for melanoma when viewed without a dermatoscope.

1. can reach very large sizes and in advanced cases is practically untreatable.

Photo in the initial stage

Unfortunately, basal cell skin cancer is extremely difficult to diagnose on early stages, i.e. at minimum sizes. Here are some photos:

Diagnosis of basalioma in the early stages, with a small tumor size, can present significant difficulties. Only a combination of a comprehensive examination of the entire skin, a thorough clarification of the history of the formation and dermatoscopy will help in establishing the diagnosis of basalioma at an early stage.

Basaliomas with high and low risk of recurrence (NCCN, 2018)

Notes

1. Localization regardless of size can be a sign of high risk
2. Histological forms of low risk: nodular (nodular), superficial, keratotic, piloid, with differentiation towards skin appendages, Pinkus fibroepithelioma
3. Area H means high risk regardless of size
4. Morpheus-like, basosquamous (metatypic), sclerosing, mixed infiltrative, micronodular in any part of the tumor

Only one of the factors from the right or left column is sufficient to assign a tumor the status of "high risk of recurrence".

Basalioma treatment

The main goal of the treatment of basal cell carcinoma is the complete removal of the tumor with the maximum preservation of the cosmetic properties and functions of those parts of the body where this neoplasm has developed.

Usually, best result ensured surgical methods. However, the desire to preserve functionality and cosmetic properties may lead to the choice radiotherapy as the main method of treatment.

Depending on the risk of recurrence (see above), the approach to treating basalioma may vary.

In patients with superficial basalioma and low risk of recurrence, when surgery or radiation therapy is contraindicated or not applicable, may be used following methods treatment:

• 5-fluorouracil ointment;
• ointment "Imiquimod" ("Aldara", "Keravort");
• photodynamic therapy;
• cryodestruction.

Micrographic surgery according to Mohs may be recommended for patients at high risk of relapse.

Chemotherapy for basalioma, it includes hedgehog signaling pathway inhibitors vismodegib (Erivedge) and sonidegib (Odomzo). These drugs can help when surgical methods, like radiation therapy, are inappropriate or contraindicated.

What you need to know about basalioma?

• In the vast majority of cases, basalioma not poses a threat to life.
• If the answer is basal cell carcinoma during a histological examination of a distant formation, there is nothing to worry about. It is important to make sure that education is removed fully- be sure to consult with an oncologist.
• If after removal of the basalioma in the histological examination there is the phrase “tumor cells in the resection margin” or something similar, it is necessary further treatment to completely remove the tumor.
• Strongly not I recommend removing the basalioma without histological examination, because even a very typical looking education may not be what it seems at first glance.
• Basaliom needs treat. Observation is a bad option for such a diagnosis. Treatment of advanced forms (see photo of the ulcerative form) is extremely difficult and expensive.
• If you have already had a basalioma removed, you need to regularly undergo an examination of the entire skin by an oncologist in order to possibly identify another such tumor.
• Probability of metastasis in the metatypical (basosquamous) histological type it is higher than in other species.

Squamous cell carcinoma

It is less common than basalioma, the second most common type of skin cancer and has a slightly less favorable prognosis. However, it should be noted that the course of the disease much less malignant than melanoma.

Metastases occur relatively rarely - an average of 16% of cases. In patients with squamous cell skin cancer less than 2 cm in size, the 5-year survival rate is about 90%, with large sizes and tumor invasion into the underlying tissues - less than 50%.

It can occur on any part of the body, including the genitals and mucous membranes, but most often in places exposed to sunlight.

Symptoms and signs

The appearance of squamous cell skin cancer depends largely on the clinical form of the disease.

keratinizing form- an elevation or a flat surface covered with horny scales that can grow and fall off. May bleed if damaged.

It must be remembered that under the mask skin horn it is the keratinizing form of squamous cell carcinoma that may be hiding. In this regard, such formations should always be removed only with a histological examination:

Nonkeratinizing endophytic form(growing in the direction of surrounding tissues). Most often it looks like a long-term non-healing wound or ulcer, which can deepen and expand over time.

Exophytic non-keratinizing form squamous cell skin cancer looks like a nodule that rises above the level of the skin. The surface of the node may be eroded or wet.

Photo in the initial stage

The initial stage of squamous cell carcinoma is understood as a condition when the malignant process is limited to the epidermis - the uppermost layer of the skin. Indicated in the diagnosis as in situ or intraepidermal squamous cell carcinoma. This disease is not life threatening if removed completely.

There are 2 forms of this phase of the disease:

Most often it is represented by single flat plaques, with clear boundaries, asymmetric shape, uneven edges. The size reaches 7–8 mm. Education can gradually increase, peeling or crusting is often noted on the surface.

The color is red or brown, located on any part of the body.

On my own behalf, I will add that in my practice, histologically confirmed Bowen's disease met only once. It looked like a small (3 x 4 x 3 mm) flesh-colored lump with a smooth surface on the skin of the shaft of the penis in a 43-year-old man.

The second form of early-stage skin cancer that develops most often on the skin foreskin penis or glans. Much less often, the disease affects the female external genitalia.

The most common appearance of Keyr's erythroplasia is a bright red spot with clear boundaries, a wet, shiny surface.

Treatment of squamous cell skin cancer (NCCN, 2018)

As in the case of basalioma, squamous cell carcinoma is divided into groups of high and low risk of recurrence and metastasis.

Area H: face mask (including eyelids, eyebrows, skin around the eyes, nose, lips [skin and red border of the lips], chin, lower jaw, skin/furrows in front of and behind the auricle, temples, ears), genitals, palms and feet.

Area M: cheeks, forehead, scalp, neck and shins

Region L: Trunk and limbs (excluding lower legs, palms, feet, nails and ankles)

Notes

1. The rim of hyperemia should be taken into account when measuring the size.
2. An excisional biopsy is preferred over an incisional one.
3. The modified Breslow thickness measurement should rule out parakeratosis and crusting and should be taken from the base of the ulcer, if any.
4. Localization, regardless of size, can be a sign of high risk.
5. Area H implies high risk regardless of size.

The basic principles and methods of treatment for squamous cell carcinoma are the same as for basalioma.

The main goal is to maintain functionality and cosmetic qualities. The most effective is considered surgical method– removal of the tumor with the capture of 4-6 mm of healthy tissue with a low risk of recurrence and metastasis. Recommended for high risk tumors micrographic surgery according to Mohs or excision in a wider range than at low risk.

Radiation therapy applicable in cases where other methods cannot be used. Platinum drugs (cisplatin, carboplatin), as well as EGFR inhibitors (cetuximab) can be used in chemotherapy for squamous cell carcinoma.

How not to get skin cancer? What to avoid?

Sunlight. The most proven cause of both types of skin cancer, however, like melanoma, is exposure to sunlight. If you like to visit hot countries, you have blond hair and skin, or your work is related to prolonged exposure to the sun, you should seriously take care of UV protection.

Precancerous skin diseases- the next factor that may precede the development of the squamous form: actinic (solar) keratosis and cheilitis, leukoplakia, papillomavirus infection of the mucous membranes and genitals. This type of tumor can also develop against the background of cicatricial changes after burns or radiation therapy.

Contact with carcinogens

Various chemicals can lead to the development of skin cancer: arsenic and petroleum products.

Weakened immune system. People who take immunosuppressants after organ transplants or who are HIV positive have an increased risk of developing squamous cell skin cancer.

Summary

Skin cancer in the vast majority of cases is not a fatal disease. In the early stages, it is treated quite successfully, there are a lot of doctors in the arsenal different methods. In the case of aggressive forms or a long course without treatment, skin cancer can be life-threatening.

Bibliography

1. Gantsev Sh. Kh., Yusupov AS Squamous cell skin cancer. Practical oncology. 2012; 2:80-91.
2. Miller AJ, Mihm MC. melanoma. N Engl J Med. 2006; 355:51-65.
3. I. A. Lamotkin. Clinical dermato-oncology: atlas / M.: BINOM. Knowledge Lab, 2011.

Basalioma (basalioma)

In the WHO International Histological Classification of Tumors (1980), basalioma is designated by the term "basal cell carcinoma". She represents slowly developing tumor, which has the ability to locally invasive and destructive growth, practically does not metastasize (or in very rare cases) and occurs in the epidermis or in the appendages of the skin.

Basalioma can occur in people of both sexes, at a young and old age, on any part of the skin. However, most often it develops in people over 40 years of age, and its predominant localization is the face (periorbital region, nose, nasolabial folds), as well as the temporal, parotid region, skull skin, neck. Basalioma can occur on intact skin or against the background of pathological processes that preceded it: late x-ray dermatitis, foci of cicatricial atrophy that developed with tuberculous and lupus erythematosus, as well as some connective tissue tumors (histiocytoma, etc.).

According to the clinical picture, there are superficial, tumor, ulcerative, pigmented and scleroderma-like forms of basalioma.

Superficial form of basalioma characterized by the appearance of an initially limited scaly patch of pink color. In the future, the spot gradually acquires clear contours, oval, round or irregular shape. On its periphery, small, dense nodules appear, gleaming in side illumination, merging with each other and forming a roller-like edge raised above the level of the skin with a slight depression in the center. The tumor acquires a dark pink, brownish, grayish, and with a pigmented form, a bluish, purple or dark brown color. Such lesions may be solitary or multiple. The multiple form of superficial basalioma often occurs in blondes living in a climate zone with increased insolation, and can be combined with freckles, nevus cell nevus, multiple foci of seborrheic keratosis, and Bowen's disease (Fig. 77). Among the superficial forms, self-scarring, or pagetoid, basalioma is distinguished, which is characterized by peripheral growth of the lesion, in the center of which an atrophy zone is formed, and along the periphery - chains of small, dense, opalescent nodules. Such plaques can reach a significant size (diameter up to 5-7 cm or more).

Tumor form basalioma is characterized by the appearance of a nodule, which gradually (over several years) increases in size, reaching 1.5-3 cm or more in diameter, acquires a rounded shape, pale pink or stagnant pink color. The surface of such a formed tumor can be smooth with pronounced telangiectasias, sometimes covered with grayish scales, or its central part is ulcerated and covered with dense bloody crusts (Fig. 78). Sometimes the tumor protrudes significantly above the level of the skin, may have a stalk (the so-called fibroepithelial type). Depending on the size of the tumor, small- and large-nodular forms of basalioma are distinguished. When the nodes merge, a tumor conglomerate (a conglomerated form of basalioma) can form.

Ulcerative form basalioma can form as a primary variant of the tumor or be the result of a superficial or tumor form of the neoplasm (Fig. 79). The characteristic clinical signs of the ulcerative form of basalioma as the primary variant of the tumor are a funnel-shaped ulceration of a relatively small size and a massive infiltrate (tumor proliferation) soldered to the underlying tissues (tumor proliferation) with fuzzy boundaries, which are much larger in size than the ulcer itself. This form of ulcerative basalioma is isolated under the name "ulcus rodens" (Fig. 79). In some cases, the tumor ulcerates especially intensively, destroys the underlying tissues, grows in depth and along the periphery (ulcus terebrans). Sometimes the ulcerative form of basalioma is accompanied by papillomatous, warty growths (ulcerative-papillary form), characterized by particularly intense endophytic and exophytic growth, and with “dangerous” localization (corner of the eye, eyelid, parotid, temporal region) can lead to death.

Scleroderma-like the form of basalioma is a rare clinical variety. In this case, the tumor looks like a dense whitish plaque with slightly raised edges. Usually this form of basalioma develops very slowly, grows along the periphery, in its central part there may be telangiectasias.

The histological features of basalioma are even more varied than its clinical features. The main pathomorphological criterion, common to all diverse forms of basalioma, is the presence of tumor cells that mimic the basal cells of the epidermis. This similarity is especially pronounced in the peripheral zone of tumor proliferates, where the cells are located like a palisade and differ from the usual basal cells of the epidermis by the absence of intercellular processes and large, intensely stained nuclei.

Many authors give various histological classifications of basalioma. General essence they are reduced to the isolation of solid, cystic, adenoid tumor types and varying degrees of differentiation of the histological picture of basalioma in the direction of the hair follicle (trichobasalioma), elements of the sebaceous glands, sweat glands, complex structure, etc. It should be emphasized that various clinical forms of the tumor practically do not differ from each other histologically. Allocate only superficial, multicentric, scleroderma-like and fibroepithelial histological types of basalioma with characteristic clinical features.

Differential diagnosis of basalioma should be carried out in relation to one or another clinical form of neoplasm: superficial, pigmented, scleroderma-like, tumor and ulcerative.

The superficial solitary form of basalioma should be differentiated from lichen planus, lupus erythematosus, Bowen's disease, seborrheic keratosis.

With lichen planus in contrast to the superficial solitary basalioma, one lesion almost never occurs, especially only on the face, where basalioma is most often observed. However, in cases of localization of the formed focus of the superficial form of basalioma on the neck or on the skin of the trunk, it may resemble the atrophic form of lichen planus. The latter differs from basalioma in short terms of development, dark brown, lilac opalescent color. On the periphery of it there is a shiny roller, in which it is impossible to distinguish individual nodules (pearls), so characteristic of basalioma. The decisive diagnostic feature that testifies in favor of lichen planus is the presence of specific polygonal papules with an umbilical indentation in the center on other areas of the skin and often on the oral mucosa. In doubtful cases, a cytological examination, and especially a histological one, makes it easy to distinguish lichen planus (degeneration of cells of the basal layer of the epidermis, washed out by cells of a strip-like infiltrate) from basalioma (tumor nests, as if suspended from the basal layer of the epidermis).

lupus erythematosus in the presence of a limited formed focus of small size with atrophy in the center, it may have an external resemblance to a superficial basalioma. Anamnestic data (relapses of lupus erythematosus in the spring and summer seasons), as well as the clinical features of the lesion in lupus erythematosus, characterized by a peripheral zone of erythema, in the center of which, against the background of atrophy, can be observed remnants of follicular hyperkeratosis, help to distinguish lupus erythematosus from it. In addition, with lupus erythematosus, only one small lesion is rarely observed. In most cases, there are similar lesions on the nose with a transition to the cheeks (in the form of a butterfly), on the auricles, in the area of ​​the red border of the lips, which is not typical for basalioma. If basalioma is suspected, it is necessary to conduct a cytological or histological examination; which, in contrast to lupus erythematosus, in basal cell carcinoma allows to identify tumor cells.

Bowen's disease sometimes it is clinically difficult to distinguish from the superficial form of basalioma, especially in cases where the latter is represented by a large plaque, on the surface of which there are serous-cortical layers. Unlike superficial basalioma, the lesion in Bowen's disease has uneven outlines and a mottled picture: areas of cicatricial atrophy are combined with severe hyperkeratosis and erosive-ulcerative changes. In addition, the peripheral zone of the plaque in Bowen's disease seems to be raised above the surrounding skin, in contrast to the superficial basalioma, there are no nodular elements in the marginal zone that form a ridge-like edge. In differential diagnosis, the results of cytological (with basalioma, layers of small tumor basalioma-like cells, with Bowen's disease, elements with squamous differentiation) and histological (with basalioma, tumor proliferates in the form of nests suspended from the epidermis, with Bowen's disease, acanthosis with areas of cell discomplexation, nuclear polymorphism, dyskeratosis of individual cells, i.e., the histological picture of intraepidermal cancer) studies.

The superficial multiple form of basalioma should also be differentiated from disseminated form of lipoid necrobiosis and syndrome. Goltz-Gorlin.

Disseminated form of lipoid necrobiosis in contrast to the superficial multiple basalioma, it is characterized by flat plaques of a round or oval shape, pinkish-yellowish in color with an erythema zone along the periphery and slight induration or atrophy in the center. Often such patients or their relatives are diagnosed with diabetes mellitus. The disease can occur in young and adulthood, while multiple superficial basalioma is more common in the elderly. The histological picture of lipoid necrobiosis, in contrast to superficial multiple basalioma, is characterized by granulomatous and necrobiotic processes in the dermis and the absence of changes (including atrophy) of the epidermis.

Goltz-Gorlin syndrome- a hereditary disease, in contrast to the superficial multiple form of basalioma, is characterized by multiple nevoid basaliomas that occur in young people or exist from birth. Such basaliomas are combined with various malformations - cystic formations in the bones of the jaws and ribs, as well as with pigmented vascular nevi. Thus, these two diseases can only be distinguished on the basis of anamnestic data and additional clinical symptoms characteristic of the Goltz-Gorlin syndrome, since the clinical and histological features of the lesions are identical.

The scleroderma-like form of basalioma should be differentiated from limited scleroderma, Pasini-Pierini atrophoderma, scleroatrophic lichen.

Limited scleroderma unlike scleroderma-like basalioma, it is characterized by large (sometimes 10 cm in diameter or more) lesions in the form of dense waxy or mauve-colored plaques with regular outlines and a zone of congestive erythema along the periphery. In the case of complete resolution of scleroderma, atrophy with hyper- or depigmentation remains at the site of the former lesion. Scleroderma-like basalioma is characterized by a more superficially located focus of small size, whitish color, without a peripheral zone of erythema. In some cases, a barely raised ridge can be found in the tumor zone, which has never happened with plaque scleroderma. Histological studies reveal characteristic nests and strands of tumor cells surrounded by a cicatricial stroma (Marfea type) in scleroderma-like basalioma, while in limited scleroderma there is homogenization of collagen fibers and moderate atrophy of the epidermis.

Atrophoderma Pasini-Pierini in contrast to scleroderma-like basalioma, it is characterized by the appearance, more often in women, of spots of rounded or irregular outlines of various sizes of stagnant pink, cyanotic color with a purple zone along the periphery. In the future, superficial cicatricial atrophy may develop in the central part of the spots. Histologically, Pasini-Pierini atrophoderma is easily distinguished from scleroderma-like basalioma based on the homogenization of collagen fibers, connective tissue edema, and epidermal atrophy.

Lichen sclerosus(syn.: Zumbusch white lichen) may bear some resemblance to scleroderma-like basalioma when considered as an isolated element. However, in most cases, unlike scleroderma-like basalioma, the lesions in this dermatosis are multiple, their surface sinks and has a whitish appearance of wrinkled tissue paper, which is uncharacteristic of basalioma.

The pigmented form of basalioma should be differentiated from precancerous melanosis Dubrey and malignant melanoma.

Precancerous melanosis of Dubrey differs from pigmented basalioma in its clinical picture - an unevenly colored (from light brown to black) plaque with polycyclic outlines and histological features. The latter consist in the fact that the foci of precancerous melanosis are characterized by the accumulation of atypical melanocytes in the epidermis, while in pigmented basalioma, despite the accumulation of unchanged melanocytes between tumor cells and the content of a large amount of melanin, in the stroma, there are elongated prismatic cells typical of this neoplasm. , surrounding tumor proliferates like a palisade, which is not observed with Dubrey's melanosis.

malignant melanoma differs from pigmented basalioma in its clinical features, which consist in the development of a smooth, domed or tuberous dark brown or black plaque, sometimes large, easily injured and bleeding. The tumor often develops from a precancerous Dubrey melanosis, a blue nevus, or a giant warty pigmented nevus that preceded it. In this regard, in the differential diagnosis of malignant melanoma and pigmented basalioma important role history plays. The localization of lesions is also of some importance, since the foci of pigmented basalioma are located mainly on the face, and malignant melanoma - on any part of the skin. Of decisive importance in the differential diagnosis are sometimes the results of histological examination. It should be emphasized that if a malignant melanoma is suspected, a biopsy in order to obtain material for histological examination should be carried out only after a total, within a wide range, excision of the tumor or simultaneously with it. An approximate differential diagnostic criterion for malignant melanoma and pigmented basalioma is the use of an isotope method with radioactive phosphorus (34 R). Accumulation of the isotope in the lesion by more than 200% compared with a symmetrical area of ​​intact skin (compared to clinical features pathological process and anamnestic data) testifies in favor of malignant melanoma.

The tumor solitary form of basalioma should be differentiated from necrotizing (calcified) epithelioma of Malerba, eccrine spiradenoma, fibropapillomatous malformation, atheroma, adenoma sebaceous glands, keratinizing squamous cell carcinoma, lymphocytoma, eosinophilic granuloma, keratoacanthoma.

Necrotizing (calcified) epithelioma of Malherba differs from the tumor form of basalioma primarily in its stony density, large size (several centimeters in diameter), and also in that it occurs not only in adults, but also in children and young men. Histological examination allows us to establish that Malherbe's epithelioma, in contrast to the tumor form of basalioma, is located in the deep sections of the dermis or in the subcutaneous fatty tissue, surrounded by a capsule, not associated with the epidermis, but comes from the hair matrix. In addition, this tumor is characterized by the presence of shadow cells with degenerating, decaying nuclei and the deposition of calcium salts both in the cytoplasm of cells and in foci of necrosis.

Eccrine spiradenoma clinically differs from the tumor form of basalioma in that it develops in most cases in young people, is localized not only on the face, but often on the anterior surface of the trunk, has the appearance of a bulging, dense, painful node on palpation. At the same time, the epidermis above the tumor is not changed, its pattern is not smoothed. Unlike basalioma, eccrine spiradenoma may spontaneously resolve. Histologically, it differs from the tumor form of basalioma in that it is located in the deep parts of the dermis, is not associated with the epidermis, has a lobed structure, glandular and cystic structures, and it lacks palisade-shaped prismatic cells along the periphery of tumor proliferates, which are so characteristic of basalioma.

Fibropapillomatous malformation has some similarities with the fibroepithelial type of tumor solitary basalioma. Both tumors rise above the level of the skin, may be pedunculated, have a pinkish-matte color. The differences lie in the fact that with basalioma the lesion is dense, the skin over it is tense, often riddled with telangiectasias, and the fibropapillomatous malformation of a soft doughy consistency, although it can be more dense, mobile, the skin over it is thinned, can be folded, and unlike basalioma, it occurs in childhood or adolescence. Histologically, fibropapillomatous malformation differs from the tumor form of basalioma in that it is based on connective tissue with fibrosis and hyalinosis, covered with a thinned epidermis.

Atheroma in unlike the tumor form of a solitary basalioma, it has an elongated-rounded shape in the form of a bump and a dense consistency, soldered to the underlying tissues, can suppurate, and then its surface becomes soft, the epidermis becomes thinner, breaks through and the contents of the atheroma are evacuated. Histological atheroma differs from the tumor form of basalioma in that it is a cyst lined with epithelium, in which there are no tumor basaloid cells.

sebaceous adenoma, as well as the tumor form of basalioma, it is more often localized on the face, has a rounded, spherical shape, dense doughy texture, yellowish-pink color, its diameter is 0.3-1 cm. Unlike the tumor form of basalioma, sebaceous adenoma occurs in young people and children, there are no telangiectisias on its surface and for a long time it practically does not change. Histologically, the adenoma of the sebaceous glands has a lobular structure, is located in the dermis, is not associated with the epidermis, which is not changed or thinned. On the periphery of the lobules of the sebaceous gland there are growths of basaloid cells, but they differ from tumor cells in basalioma, as they are prone to squamous differentiation. The histological picture of the tumor form of basalioma with sebaceous differentiation differs from the above histological picture of sebaceous gland adenoma in that among the tumor proliferates typical of basalioma, there are cells with light, foamy protoplasm, in which neutral fat is found

Keratinizing squamous cell carcinoma (exophytic form) may have a clinical similarity with the tumor form of basalioma in cases where its surface is ulcerated or covered with cortical layers. The difference between them lies in the fact that even with prolonged existence and ulceration, a basalioma retains a smooth peripheral zone in the center, while in squamous cell carcinoma, in the case of exophytic growth, there are papillary growths on the surface of the tumor, to which purulent discharge with an unpleasant odor is attached. The base of the plaque in squamous cell carcinoma often increases in size, and with the collapse of the central part and the formation of ulcerations along the periphery, it remains a dense epithelial roller. The tumor acquires uneven outlines, painful. Histologically, keratinizing squamous cell skin cancer differs from the tumor form of basalioma by the proliferation of cells of the spiny layer of the epidermis, resulting in the formation of layers of tumor cells with discomplexation, nuclear polymorphism, severe anaplasia and the formation of "pearls" - the result of keratinization of individual cells of the spiny layer of the epidermis. Along the periphery of tumor proliferate complexes there are small dark elements, but there is no palisade-like arrangement of high prismatic cells so characteristic of basalioma. Unlike the tumor form of basalioma, keratinizing squamous cell carcinoma metastasizes.

Lymphocytoma skin in the case of localization of a single focus on the face may have a clinical similarity with the solitary, tumor form of basalioma. In contrast, lymphocytoma is characterized by a rich pink or stagnant red color, its surface is not spherical, as in basalioma, but more flattened and there are no telangiectasias, often observed in tumor forms of basal cell carcinoma, on it. For the differential diagnosis of the tumors under consideration, anamnetic data are also important. Basalioma usually develops gradually and exists long time(sometimes for many years), and lymphocytoma occurs suddenly. In a cytological examination of a lymphocytoma, it is not possible to detect an accumulation of tumor basalioma-like cells, and a histological examination in the dermis reveals a diffuse (Jesner-Kanaf lymphocytic infiltration) or follicular (Spigler-Fendt lymphocytoma) infiltrate, consisting of lymphocytes and histiocytes.

Eosinophilic granuloma in those cases when it is not represented by flattened, infiltrated plaques, the most characteristic of this tumor, but by a limited tumor-like, nodular element, it can clinically resemble the tumor form of basalioma. However, eosinophilic granuloma is easily distinguished from it by its brownish-bluish coloration and the sudden onset of the lesion, often after trauma or a bite. In doubtful cases, a histological examination helps to establish the correct diagnosis: an eosinophilic granuloma is characterized by a polymorphic infiltrate in the dermis with the presence of eosinophils, separated from the unchanged epidermis by a zone of normal collagen, while in basalioma there is a proliferation of tumor cells emanating from the epidermis or skin appendages.

Tumor multiple form of basalioma should be differentiated from Brook's adendrial cystic epithelioma, cylindroma, trichoepithelioma.

Brook's adenoid cystic epithelioma in contrast to the tumor multiple form of basalioma, it is more common in young women and children. Foci, lesions are multiple, monomorphic, do not ulcerate, tend to cluster or are arranged symmetrically, which never happens with tumor multiple basalioma. Histologically, Brook's adenoid cystic epithelioma differs from basalioma in the presence of cysts with incompletely formed hair, strands of basaloid cells, and ducts of eccrine sweat glands.

The ulcerative form of basalioma should be differentiated from squamous cell skin cancer, metatypical skin cancer, Bowen's disease.

Differential diagnosis with squamous cell carcinoma skin should be carried out taking into account its main clinical forms: exophytic-ulcerative, including papillary, and endophytic-ulcerative.

Exophytic-ulcerative form of squamous cell carcinoma, as well as its papillary form, are similar to the ulcerative-papillary form of basalioma. The differences lie in the fact that a tumor in exophytic-ulcerative form of squamous cell carcinoma can develop on any part of the skin, while the favorite localization of basalioma is the scalp, eyelids in the corners of the eyes. Often, squamous cell carcinoma develops on scarred skin, while the papillary ulcerative form of basalioma often occurs on apparently unaltered skin. The growth of squamous cell carcinoma is much more active than that of basalioma. In the formed focus of the exophytic-ulcerative form of squamous cell carcinoma, the peripheral zone is well expressed in the form of an epithelial shaft, while the papillary-ulcerative form of basalioma is represented by diffuse papillary growths in the area of ​​the lesion without signs of a ridge-like marginal zone. In the exophytic-ulcerative form of squamous cell carcinoma, in some cases, metastases are found in regional lymph nodes, and in the ulcerative-papillary form of basalioma, regional lymph nodes can only be reactively changed in the event of a secondary infection.

In some cases, the clinical picture in these forms of neoplasms is so similar that it is possible to establish a final diagnosis only on the basis of the results of a histological examination. It makes it possible to detect complexes of tumor proliferates in squamous cell carcinoma, consisting of spiny cells with the phenomenon of anaplasia, discomplexation and individual keratinization of individual cells ("pearls"). At the same time, in the ulcerative-papillary form of basalioma, regardless of the direction of differentiation of tumor cells, one can always find a palisade-like arrangement of high prismatic cells along the periphery of tumor complexes, typical for this tumor.

Endophytic-ulcerative form of squamous cell carcinoma must be differentiated from ulcus rodens and ulcus terebrans.

Ulcus rodens differs from the endophytic-ulcerative form of squamous cell carcinoma in its favorite localization of lesions in the chin, base of the nose, and corners of the eyes. characteristic clinical feature This type of ulcerative form of basalioma, in contrast to squamous cell carcinoma, is a pronounced infiltration of the tissue, far beyond the ulcer itself, and therefore the entire tumor conglomerate is, as it were, drawn into the underlying tissues, motionless. In this case, the ulcer itself can be small in size (diameter about 0.5-1 cm), irregularly cone-shaped, penetrates deep into the skin. With the endophyto-ulcerative form of squamous cell carcinoma in the marginal zone, an elevation can always be found - an epithelial ridge, the size of the ulcer often corresponds to the boundaries of the tumor, discharge is often observed. fetid odor, which is absent in ulcus rodens.

The difference between squamous cell carcinoma and ulcus terebrans is basically the same as from ulcus rodens. However, this type of ulcerative form of basalioma is characterized not only by invasive-destructive growth in the underlying tissues, but also by the spread of the tumor along the periphery, and therefore it often occupies vast spaces (temporal and ocular regions, forehead, skull, etc.). The tumor can destroy the underlying tissues, including bones, is characterized by intensive growth and, depending on the localization, can be fatal.

Histologically, it is especially important to distinguish the ulcerative form of basioma from poorly differentiated squamous cell carcinoma, the complexes of which may consist of small dark cells resembling basaloid ones. In this case, the main histological differential diagnostic criterion is a palisade-like arrangement of high prismatic cells around tumor nests in basalioma.

metatypical cancer differs from the ulcerative form of basalioma in the clinical picture. In metatypic cancer, a rather large plaque (diameter 3-5 cm or more) of irregular shape usually appears, along the periphery of which a ridge typical of basalioma, consisting of individual nodules ("pearls"), is often traced, and the surface of the tumor can be covered with dense serous-bloody crusts with areas of ulceration.

The localization of such lesions in metatypical cancer may be different, but more often they are located in the area of ​​the shoulder girdle, on the neck, in the behind-the-ear folds.

Histologically, the ulcerative form of basalioma differs from metatypical cancer in that, along with typical tumor nests consisting of small dark cells surrounded by prismatic cells characteristic of basal cell carcinoma, pronounced squamous differentiation is observed in metatypical cancer. As for such criteria for the differential diagnosis of metatypical cancer and ulcerative basalioma, such as mitotic activity, the frequency and spectrum of pathological mitoses [Bogatyreva I. I. 1983], they cannot be considered absolutely reliable, since in different parts of the same lesion with metatypical cancer, these indicators may be different. For this reason, the most reliable method differential diagnosis of these neoplasms is a comparison of the clinical picture of the tumor with the result of a histological examination of serial sections from different areas of the neoplasm.

Bowen's disease differs from the ulcerative form of basalioma in that it is cancer in situ. Clinically, Bowen's disease is more often manifested by a solitary plaque with raised edges, the surface of which is eczema-like or has a hyperkeratotic character. Often, with Bowen's disease, a variegated surface of lesions is observed: areas of cicatricial atrophy are combined with superficial erosions and scaly-cortical layers. At the same time, plaques are not soldered to the underlying tissues and rarely turn into an ulcer, with the exception of cases when Bowen's disease transforms into squamous cell carcinoma. Histologically, Bowen's disease differs from the ulcerative form of basalioma in that it is an intraepidermal cancer and is characterized by acanthotic growths of the epidermis, within which discomplexation of cells of the spinous layer, nuclear polymorphism, and areas of dyskeratosis are expressed.

In contrast to Bowen's disease, the ulcerative form of basalioma is characterized by the proliferation of small tumor basaloid elements, the nests of which are surrounded by high prismatic cells.

The most common type of non-melanoma skin cancer is basal cell skin cancer (basalioma), which accounts for 45 to 90% of all skin cancers. The incidence rates vary significantly - from low in regions with a small flux of solar radiation to high in regions with hyperinsolation.

In medical statistics, a special account of the incidence of basalioma is not kept. At the same time, the incidence in the Russian Federation of any type of non-melanoma epithelial tumor per 100,000 population is about 43 people and ranks first in the structure of all cancer incidence. Its annual growth is approximately 6% among the male population and 5% among the female population.

Risk factors

Basal cell skin cancer is a slowly growing and recurring malignant tumor that develops in the epidermal layer or skin appendages, has a destructive growth (capable of penetrating into surrounding tissues and destroying them), and in rare cases, the ability to metastasize and lead to death. exodus.

The etiopathogenesis of the tumor is not well understood. However, in the mechanisms of the development of the disease, the main role of one of the intracellular molecular signaling pathways (SHH) that controls the processes of cell metabolism, their growth, motility, synthesis of RNA based on DNA and other intracellular processes is considered to be proven.

It is assumed that the difference in morphological forms and biological behavior (degree of aggressiveness) of basal cell skin cancer is due to genetic and supragenetic regulatory mechanisms. The disease begins to develop as a result of mutations in a certain chromosome gene encoding the SHH signaling pathway receptor, resulting in its pathological activity, followed by the growth of atypical cells.

The factors contributing to the mutation of genes and the implementation of the mechanisms of development of cancer cells are:

1. The influence of the sun's rays. Their role is of paramount importance. Moreover, if for development it is the intensity of ultraviolet rays that is more important, then for - duration, "chronic" nature, that is, the cumulative effect of their exposure. This probably explains the difference in the localization of malignant tumors: melanomas, as a rule, develop in closed areas of the body, basaliomas - in open ones.
2. Age and gender, the influence of which is also partly explained by the cumulative effect of UV rays - in 90% of basal cell carcinoma develops at the age of 60 years, and the average age of those seeking medical help for this reason is 69 years. Skin cancer occurs more often in men than in women. Most likely, this is due to the more frequent and prolonged exposure to the sun due to the peculiarities of professional activity. At the same time, such a difference in the frequency of the disease in last years increasingly obliterated due to changes in lifestyle and women's fashion(open areas of the body).
3. Exposure to the skin of X-ray and radioactive rays, high temperature (burns), inorganic compounds and arsenic compounds contained in contaminated water and seafood.
4. Chronic inflammatory processes skin, frequent mechanical trauma on the same area of ​​the body, skin scars.
5. Chronic conditions associated with immunosuppression in diabetes, hypothyroidism, HIV infection, blood diseases (leukemia), taking glucocorticoid drugs and immunosuppressants for various diseases.
6. Individual characteristics of the body - a tendency to form freckles in childhood, skin phototype I or II according to the Fitzpatrick classification (in persons with dark skin, basal cell carcinoma develops much less frequently), albinism, genetic disorders (hereditary xeroderma pigmentosa).
7. Localization of the neoplasm. So the risks of a tumor and its more frequent recurrence are higher with localization in the head, especially the face, neck, and much less with a primary lesion, for example, the skin of the back and extremities.

Risk factors for recurrence are tumor subtype, its nature (primary or recurrent), and size. In the latter case, such an indicator as the maximum diameter of the carcinoma (more/less than 2 cm) is taken into account.

Symptoms of basal cell skin cancer

This tumor is characterized by very slow growth (many months and even years). The peripheral sections of the focus have the greatest growth activity. Here, the phenomena of cell apoptosis are noted, as a result of which an erosive or ulcerative surface is formed in the center of the neoplasm.

This fact is taken into account in surgical treatment, for the choice of the volume of which it is very important to define the boundaries of the peripheral growth zone as clearly as possible, since cancer cells with the greatest aggressiveness are localized in it.

In the case of long-term development, the initial stage of basal cell carcinoma gradually passes into the next, which are characterized by infiltration and destruction of deeper underlying soft tissues, periosteum and bone, metastasis to regional lymph nodes. In addition, pathological cancerous tissues tend to spread along the periosteum along the tissue layers along the nerve branches. The most vulnerable in this regard are the boundary zones of contact of the embryonic layers, represented, for example, by nasolabial folds on the face.

The histopathological picture is characterized by the presence of cells containing a small amount of cytoplasm and large ovoid-shaped nuclei, which consist mainly of matrix. The index, determined by the ratio of the nucleus to the cytoplasm, significantly exceeds that of normal cells.

The intercellular tissue (stroma) grows along with the tumor cells. It is located in bundles between cell strands and divides them into separate lobules. In the peripheral parts, the formation is surrounded by a layer of cells, the arrangement of the nuclei of which resembles a palisade. This layer contains cells with a high potential for aggressiveness and malignant growth.

In accordance with clinical and histological features, several subtypes, or variants of basal cell carcinoma, are distinguished.

Nodular (nodular) or solid basal cell carcinoma

It averages 81% of all cases of the disease. It is a slowly growing formation of a rounded shape and pink color that rises above the healthy surface of the skin, the size of which in the largest diameter can range from a few to 20-30 millimeters.

The entire focus is represented by papules with a pearlescent shiny surface, and small branched telangiectasias. The surface of the entire tumor bleeds easily with minor trauma. Its size gradually increases, and a crust appears in the center over time, and in the future - an ulcer. Over 90% of the formations of this variant are localized in the head (cheeks, nasolabial folds, forehead, eyelids, auricles) and neck.

On histological examination, a solid tumor consists of compactly grouped epithelial cells, similar to the cells of the basal layer of the epidermis, between which neutral mucopolysaccharides and glycosaminoglycans are located. These complexes have indistinct boundaries and are surrounded by elongated elements, as a result of which they have a characteristic “palisade” appearance. As a result of the progression of the destruction of normal tissue, small (of various sizes) cavities are formed in the form of cystic cells. Calcium salts are sometimes deposited in the destroyed cell mass.

1. Solid form of basal cell skin cancer
2. Sclerosing form

Ulcerative form

It is considered as a result of the natural further development of the previous version. The processes of programmed cell death (apoptosis) in the central zone of the tumor are the cause of the destruction of the malignant focus with the formation of an ulcer covered with purulent-necrotic crusts, surrounded by an elevation in the form of a roller Pink colour with small "pearls" (nodular thickenings) of a grayish color.

Basal cell carcinoma of the ulcerative form, as a rule, does not metastasize. However, it can exist up to 10-20 years, during which the ulcers increase from millimeters (1-2) to gigantic sizes (5 cm or more), penetrating deeply into the underlying tissues and destroying the surrounding structures in the course of their growth. Advanced cases can cause bleeding, purulent and other fatal complications.

surface form

It is approximately 15%. It is characterized by the appearance of a patch of pink color with raised edges, well-defined borders and a shiny or scaly surface, on which a brown crust often forms. The most common (60%) localization is various parts of the trunk and limbs. Quite often there are multiple foci. As a rule, the disease affects younger people - the average age is 57 years.

This form is characterized by benign growth - existing for decades, the tumor slowly increases in area and, as a rule, does not penetrate into neighboring tissues and does not destroy them, but after surgical treatment it often recurs in the peripheral sections of the postoperative scar.

Histologically, the formation consists of many complexes that are located only in the upper layers of the dermis up to the reticular layer. Some (about 6%) superficial tumors contain excessive amounts of melanin and are classified as a pigmented form. They have a brownish or even black color and cause certain difficulties in differential diagnosis with melanocytic tumors.

Superficial form of pathology

Pigmentary basalioma

Flat or sclerosing form of basal cell carcinoma

It averages 7%. It is a plaque with indistinct borders, raised edges and a depression. The color of the formation is flesh, ivory with a mother-of-pearl tint or reddish. Visually, it is similar to a “patch” or looks like a scar. On its surface there may be small crusts, erosions or telangiectasias. The predominant areas of localization are the head (especially the face) and neck (95%). The course of the flat form is more aggressive with germination into the subcutaneous adipose tissue and muscles, but there are no ulcerations and bleeding.

Infiltrative variant

It develops in cases of progression of nodular and flat forms of basalioma. It is characterized by a pronounced infiltrative component of the tumor, a tendency to recurrence after treatment, and a more negative prognosis.

Fibroepithelioma of Pinkus

It is a rare type of basal cell carcinoma. It is characterized by localization in the skin of the lumbosacral region and clinical similarity to fibroepithelial polyps or. Histological examination revealed epithelial strands, consisting of dark small cells of the basalioid type. The strands are interconnected and extend from the epidermis, sometimes small cysts are visible in them. Elements of the surrounding stroma are often enlarged and edematous, it contains many basophils and capillaries.

Basosquamous, or metatypical form

It is characterized by the fact that during histological examination, one part of the tumor has signs of basal cell carcinoma, and the other - of squamous cell carcinoma. Some of the metatypical lesions form as a result of the superimposition of these two types of skin cancer. The metatypical variant is the most aggressive in terms of growth, spread, and distant metastasis, similar to squamous cell carcinoma.

Basal cell neoplasia syndrome (Gorlin-Goltz syndrome)

A rare autosomal dominant disorder that presents with intermittent multiple symptoms. The most characteristic and often occurring is a combination of such signs as:

1. The presence of multiple sites of basal cell carcinoma in various parts of the body.
2. Palmar and plantar pits are dark or pink in color, which result from a defect in the stratum corneum.
3. Cystic formations in the jaw bone that can destroy bone tissue, change the shape of the jaw and lead to tooth loss. Often, these cysts are discovered incidentally on x-rays.

The course of the syndrome, as a rule, is non-aggressive - without involvement of deeply located soft tissues and bones of the face in the process. Other (also inconsistent) symptoms may be increased sensitivity to sunlight, abnormal development of skeletal bones, a large body, and some others. Even in the same family among its members, the symptoms and their combination may be different. The presence of neoplasms at a young age or their multiplicity should be the reason for the presumptive diagnosis of Gorlin syndrome.

Treatment of basal cell skin cancer

According to statistics, about 20% of patients or more with various forms of basalioma were treated with folk remedies or various external medicines before going to the doctor. Such independent therapy is unacceptable, since it is not only ineffective, but can increase the area and depth of the lesion and even provoke the development of metastases.

The main methods of treatment:

1. Surgical.
2. Close focus radiotherapy.
3. Curettage with electrocoagulation.
4. Cryodestruction.
5. Photodynamic therapy (PDT).
6. Chemotherapy.

Surgical method

It consists in elliptical excision within healthy tissues at a distance of 4-5 mm from the borders of the tumor with a mandatory subsequent histological examination of the edges of the removed area. In the case of locally infiltrative growth of the formation, an extensive resection is performed, followed by a plastic-reconstructive operation.

The effectiveness of the surgical method of treating a primary tumor is 95.2% with medium duration observation for 5 years. High rates of recurrence were noted with lesions larger than 10 mm, removal of recurrent tumors, as well as localization of cancer in the nose, ears, scalp, eyelids, and periorbital zone.

In most cases, the microsurgical technique is considered standard. It allows you to maximize the preservation of unaffected tissue areas, which is especially important during operations on the face, fingers and in the genital area. The method consists in excision of a visually visible tumor, followed by serial layer-by-layer horizontal tissue sections and their histological examination and mapping. This method makes it possible to economically achieve "clean" edges.

Close focus radiation therapy using x-rays

The main method in the presence of contraindications for use surgical excision. It is shown mainly to persons 60 years of age and older. Beam method can cause diffuse alopecia, radiation dermatitis, provoke the development of malignant neoplasms, etc.

Curettage with electrocoagulation

They are used most often in the treatment of basal cell skin cancer, due to their high availability, ease of implementation, low cost, and rapid results. The essence of the method is to remove the bulk of the affected tissues (with exophytic growth of the formation) by means of a metal curette and subsequent electrocoagulation of the tumor bed. Its disadvantages are the impossibility of histological control, a high risk of recurrence in tumors larger than 1 cm, and unsatisfactory cosmetic results (the formation of areas with reduced pigmentation is also possible).

Cryosurgery with liquid nitrogen

Despite the possibility of outpatient use, low cost procedures and satisfactory cosmetic results for the treatment of basalioma, it is rarely used. This is due to the need for repeated sessions, the impossibility of histological control, and the presence of a high percentage of relapses.

Photodynamic therapy

It is a relatively new technique in which the treatment of basal cell skin cancer with a low-wavelength laser is carried out against the background of the action of a photosensitizer and oxygen. The impact effect is:

• damage to tumor vessels;
• direct toxic effect on the cells of substances that are formed as a result of the resulting light-chemical reaction; these substances lead tumor cells to apoptosis, as a result of which the latter become foreign to the body;
• formation of an immune response to foreign cells.

Chemotherapy

It is not widely used because it is not effective enough. It can be used for superficial lesions of a small area, mainly as an adjunct to other methods or in cases where there are contraindications to their use.

With monotherapy, the effectiveness of the method can reach 70%. Systemic chemotherapy for basal cell skin cancer consists of intravenous drip of Cisplastin in combination with Doxorubicin according to the scheme or Cisplastin in combination with Bleomixin and Methotrexate also according to the scheme. In addition, creams, emulsions and ointments containing bleomycin, cyclophosphamide, prospidin, methotrexate are produced for topical use.

Forecast

The prognosis for basal cell skin cancer is generally quite favorable, since metastasis occurs mainly in cases of transformation of its various forms into a metatypical one, which metastasizes on average in 18%.

V practical activities especially important is the timely differential diagnosis of dermatological pathology and, in particular, different variants of carcinoma, which allows you to choose the right method of therapy, prevent the possibility of recurrence and achieve acceptable cosmetic results.

IN AND. Volgin, T.V. Sokolova, M.S. Kolbina, A.A. Sokolovskaya

The problem of interdisciplinary interaction in the diagnosis and choice of treatment for basal cell disease (BCCC) is currently very relevant. Most forms of BCC go beyond narrow clinical specialties to some extent and are at the intersection of two or more disciplines. This problem is of great interest to dermatologists, oncologists and surgeons. This is due, firstly, to the absolute increase in the number of patients with various forms of BCC, and secondly, the emergence of new diagnostic and treatment methods that allow for a quick diagnosis and effective removal of tumor foci.

Epidemiology

In recent decades, there has been a steady increase in the incidence of non-melanoma skin cancer worldwide. The annual increase is from 3 to 10%. In the structure of oncological morbidity of the population Russian Federation in 2007, malignant neoplasms of the skin, with the exception of melanoma, ranked second, accounting for 13.6% in female cancer patients and 9.8% in men. During the period from 1999 to 2007, the incidence of skin cancer increased 1.3 times (p< 0,01).

The growth of oncological pathology is due not only to the aging of the population, the deterioration of the environmental situation, but also to the improvement in the detection of malignant neoplasms. The incidence rate of skin cancer (excluding melanoma) increased by 34.3% between 1996 and 2006. The largest increase in the incidence of malignant neoplasms of the skin from 1995 to 2005 was registered in the Far East (31.6%), Siberian (27.5%) and Urals (19.2%) federal districts. Among malignant neoplasms of the skin, BCC is the most common, accounting for 267.8 per 100,000 population in Russia.

BCC ranks second in frequency among all malignant neoplasms after lung cancer, accounting for 11-12%. Among malignant epithelial neoplasms of the skin, BCC is in the lead, its share ranges from 75 to 97% and continues to increase steadily. According to the Moscow Cancer Registry for 2000-2003, BCC accounted for 91.5% of all non-melanoma malignant skin tumors. The annual increase in the number of patients with BCC in different countries world, according to data for 1980-1999, ranged from 40 to 65%. More than 40,000 new cases of BCC are registered annually in the United States, and the increase in the number of newly registered patients reaches 65% and ranges from 500,000 to 700,000 new cases. In the UK, between 1970 and 1992, the incidence of BCC increased 3-fold. In Australia, the incidence reaches 1000-2000 cases per 100,000 population. In Switzerland, between 1976 and 1990, registered constant growth incidence by 2.6%.

BCC most often develops over the age of 50 years. However, cases of the onset of the disease at an earlier age, starting from the age of 20, are often described. The average statistical age averages 64.4 ± 3.3 years. The share of elderly and senile people accounts for 72-78%. The likelihood of developing BCC in people older than 55 years is 4-8 times higher than in people younger than 20 years. in the Siberian federal district the age of patients with BCC in almost half of the cases exceeded 60 years. Cases of BCC have been described in girls aged 15 and 17 years.

Some aspects of the etiology and pathogenesis of BCC

Numerous experimental and epidemiological studies have established that malignancy of epidermal structures can occur in response to various endogenous and exogenous factors.

Among them, the leading ones are hereditary predisposition to carcinogenesis, ultraviolet radiation (UVI), exposure ionizing radiation, chemical carcinogens, mechanical damage to the skin, viral infections, as well as dysfunction of the immune and endocrine systems. However, specific mechanisms for the development of BCC under the influence of these factors are unknown in most cases. Features of the course of basaliomas are also determined by the age of the patients.

Genetic factors play a significant role in the pathogenesis of tumors. In patients with BCC (), a hereditary predisposition (family cases) to the development of tumors was established in 28% of cases. Of these, in more than 3/4 cases, oncological pathology was detected among relatives of the 1st degree of kinship and in the rest (21.4%) - of the 2nd degree. In recent years, great importance has been given to the study of the association of genetic markers with various diseases. Genetic markers can be blood groups, Rh factor, HLA histocompatibility antigens, etc. In chromosome 9q22.3 of the human genome, the PTCH gene was found, mutations of which lead to the development of BCC. The genes that code for blood types are also on chromosome 9q, which undergoes changes that are found in many types of cancer. In other words, cancer genes are controlled by blood group antigen genes. According to HLA-typing data of patients with BCC, it was found that multiple formations are significantly associated with HLAB14 and HLADrl antigens.

Based on a large clinical material, it was shown that in patients with BCRC, compared with healthy donors, the occurrence of I (0) and III (0B) blood groups significantly differed. Without taking into account the Rh factor, BCC developed 1.4 times more often in patients with I (0) blood group and 1.8 times less often in patients with III (0B) group. Multivariate analysis The distribution of patients with BCRC and voluntary donors, taking into account two factors (blood group of the ABO system and Rh factor), showed that in the presence of blood group III (0B) with Rh- BCRC was observed 11 times more often than with the same blood group and Rh +. In patients with group I (0) and Rh+, tumors occurred significantly 1.3 times more often than in Rh-.

Physical damage to the skin UVI stimulates the development of carcinogenesis through a direct effect on the DNA of cells. It has been proven that exposure to the skin of ultraviolet rays is accompanied by immune deficiency. Destruction of lymphocyte-activating la-antigens on the surface of lymphoid cells, impaired immune response, induction of suppressor lymphocytes, disappearance of functionally active Langerhans cells from the epidermis occur. UVR activates keratinocytes, enhances the production of certain cytokines and growth factors. In skin exposed to chronic insolation, a tendency to an increase in mast cells in the dermis was revealed. Any skin cells can undergo malignant transformation, but basal cell and squamous cell carcinomas develop more often.

UV-B rays have the greatest damaging effect, but at the cellular level, various chromophores can also absorb UV-A energy and generate free radicals. They act on membrane lipids and proteins by destroying DNA. Damage to biologically important macromolecules occurs not due to the direct absorption of light quanta by them, but as a result of the photodynamic action of substances. Low doses of UV-A, or even sub-erythemal doses, are also capable of forming pyrimidine diamers and causing DNA damage, leading to cell mutation. Skin sensitivity to sunlight depends on its type. There are 6 skin phototypes. BCC occurs under the influence of the radiant energy of the sun, mainly in people with skin photosensitivity types I and II.

The role of UVR in the pathogenesis of BCC is indicated by the high incidence of BCC in the southern regions, the overwhelming number of patients belonging to the white race, the predominant localization of foci in open areas of the skin, where the ulcerative form predominates (83%). In persons with insufficient skin pigmentation, rays with a wavelength of 290-320 nm are the main cause of the disease. Skin cancer can occur not only under the influence of natural UV radiation, but also as a result of UV exposure from industrial sources. Increased skin sensitivity to solar insolation can be caused by drugs (tetracyclines, sulfonamides, phenothiazines, thiazides, greseofulvin, etc.) and some herbs, especially if they contain coumarins.

It has been shown that mutations in chromosome 9q22.3 of the human genome can occur under the influence of UV radiation. This is confirmed by the high risk of developing skin cancer in patients with rare hereditary diseases exacerbated by photosensitivity - albinism, pigment xeroderma, nevoid basal cell carcinoma syndrome.

Chemical carcinogens, under the influence of which BCC can develop, can be hydrocarbons of oil, coal, mineral oils, resins, arsenic compounds, insecticides, herbicides, petroleum products, etc. The use of photoactive agents (coal tar, 8-methoxypsoralens) in the treatment of certain diseases , hematoporphyrins) in combination with UV-A skin exposure also leads to an increased risk of skin cancer. Experimentally identified mediators involved in carcinogenesis caused by chemical products. They are represented by a group of pro-inflammatory cytokines, often similar to those under UV exposure.

The role of chemical carcinogens in the pathogenesis of skin cancer is indicated by 25-year epidemiological studies in families where parents were in contact with potential carcinogens in production conditions. The risk of developing a tumor process in children was quite high. In foreign studies, the main focus is on fathers, since in developed countries women are much less likely to be employed in production with harmful working conditions. Studies conducted in Russia, where the share of women in industrial production is up to 46%, revealed a pronounced negative effect of harmful professional factors on parents, which affected the health of children, including the risk of developing cancer.

Radiation radiation in approximately 80% of cases comes from natural sources, including cosmic rays, UV light and natural radionuclides, especially radon gas. The remaining 20% ​​comes from various man-made sources of radio and microwave radiation, nuclear power plants and others. The pathological effect of high doses of radiation has been proven, but the total effect of low doses can be harmful to humans. X-ray, gamma and cosmic radiation are referred to as ionizing radiation. There is radiation of elementary particles - electrons, neutrons, mesons and deuterinos. X-ray and gamma radiation at a frequency of 1018-1022 Hz contribute to the emergence of malignant neoplasms of the skin, and ionizing radiation, in addition, - leukemia, osteogenic sarcomas and lung cancer. Diseases often develop 10-20 years after exposure.

The mechanism responsible for late carcinogenesis is not yet well understood. The long latent period between exposure to radiation and the development of cancer is explained by some scientists as the occurrence of the so-called induced genetic instability. Pathological genes can be passed on in a population of cells for several generations.

Anthropogenic contamination of the environment with radionuclides as a result of experimental nuclear explosions, the intensive development of nuclear energy, the use of sources of ionizing radiation in industry, transport, agriculture, science, as well as the expanding scope of X-ray and radioisotope research methods in medicine have led to an increase in external and internal human exposure.

Exposure doses from these sources in developed countries are already several times higher than levels of natural background exposure. latent period for solid tumors depends on the dose of radiation and the age of the person and averages 20-30 years. On the example of the population living around the Semipalatinsk test site, the highest incidence of BCC and melanoma is shown.

An analysis of the history data of 300 patients with BCRC made it possible to study the frequency of exposure to various carcinogens (radiation, microwave radiation, fuels and lubricants, insolation, etc.) on their bodies. More than half (57.7%) of patients with BCC were exposed to carcinogens. Among them, 61.7% had a fairly long contact with fuel and lubricants. More than half (57.3%) were exposed to insolation both at work and at home. Contact with microwave radiation occurred in 31% of patients, exposure to radiation was noted by 28.3%. These factors often overlap. In almost 2/3 of cases, BCRC patients were exposed to 2 or more carcinogens. More often they were 2 (40.7%), less often - 3 (12.8%) and 4 (7.8%). It was shown that the adverse effect of carcinogens (fuel, lubricants, radiation and microwave radiation) most often occurred in hot climates. In 72.5% of patients with BCC, who lived in the southern regions, a combined effect of these factors and insolation was found.

A similar situation was revealed for patients living in different regions with a predominance of the southern (66.4%). The fact of a delayed effect of the action of a carcinogen has been established. Tumors in 68.6% of cases occurred during the retirement period or 12.6 ± 9.3 years after the end of the carcinogen.

The study of the association of skin cancer and antigens of blood groups of the AB0 system, taking into account the impact of factors contributing to carcinogenesis, revealed interesting patterns. It was found that the frequency of BCRC formation, the intensity of growth and size of tumors depended on the conjugation of endo- and exogenous factors. Under the influence of carcinogens, BCC developed 1.7 times more often in patients with II (AO) blood group and 2 times more often in patients with IV (AB). The occurrence of BCC in the majority (82%) of cases occurred in patients exposed to carcinogens for 5 years or more. Statistical processing of the material using the Spearman correlation coefficient showed that certain carcinogens in patients with BCC with various groups blood samples were associated with the size of the tumors. If there was a history of exposure to radiation, large tumors were registered in patients with III and IV blood groups, insolation - in patients with group I, DBS - with II and III blood groups.

Virus-induced carcinogenesis is of particular importance in pathogenesis oncological diseases. This is due to the prevalence of viruses and the peculiarity of their life cycle.

Of particular interest in connection with the pronounced oncogenic potential is the human papillomavirus (HPV). The widespread introduction of molecular biological research methods has made it possible to detect more than 200 HPV genotypes. HPV infects basal epithelial cells, and different types of the virus differ in their tropism for different tissues: some are associated with damage to the skin (skin of the hands, feet and face), others infect the mucous membranes of the oral cavity, pharynx, respiratory tract and anogenital region or the conjunctiva of the eyes.

There are high and low oncogenic risk HPV. The group of viruses of high oncogenic risk also includes types of the virus that are rarely detected in cancer, but are most often associated with the development of dysplasia of varying degrees. This made it possible to separate them into a separate group - "HPV of medium oncogenic risk".

The products of early HPV genes - E6 and E7, and to a lesser extent E5 have a transforming and carcinogenic potential. The products of these genes interact with the cellular tumor growth suppressor genes p53 and Rb, which leads to their inactivation and uncontrolled growth of infected cells with the accumulation of genomic mutations in them. The affinity of E6 and E7 proteins for p53 and Rb differs in high and low oncogenic HPV types. The presence of HPV DNA in the tissues of benign epithelial tumors and BCC has been established. In patients with BCC, immunosuppression is determined, affecting the cellular link of immunity, phagocytic activity, the production of endogenous interferons, immunogbulins of classes A, M, G. The most pronounced immunodeficiency was detected in ulcerative, especially recurrent forms of BCC, which make up 64% of all basaliomas.

A decrease in the number of epidermal Langerhans cells in the skin and a violation of their function lead to a decrease in the protective mechanisms of antitumor growth. Of great importance in the differentiation and proliferation of tumor cells are cytokines that regulate apoptosis and other mechanisms of cytotoxicity in malignant neoplasms.

In patients with Gorlin-Goltz syndrome, a decrease in the activity of normal killers to 3% was revealed (at a rate of 50.4%). This leads to a pronounced deficiency of cellular immunity in the link responsible for antitumor activity, which is a prerequisite for the development of multiple lesions and pathology of internal organs in these patients. Autoimmune disorders also occur in carcinogenesis.

Classifications of basal cell skin cancer

There is no generally accepted classification of BCRC. In our country, the classification proposed by A.K. Apatenko.
All tumors were divided into three groups, including several variants:

Undifferentiated or poorly differentiated basaliomas:

A) undifferentiated basalioma of predominantly solid structure (sometimes with subtle glandular or piloid differentiation);
b) pigmented basalioma;
c) superficial multicentric basalioma.
Differentiated basaliomas:
a) with glandular differentiation (adenoid basalioma);
b) with piloid differentiation (trichobasalioma); ,
c) with sebaceous differentiation;
d) with squamous epithelial (epidermoid) differentiation;
e) complex structure (with the presence various types differentiation).
Special forms of basalioma:
a) scleroderma-like;
b) basalioma of the type of fibroepithelial tumor of Pinkus;
c) basalioma that occurs in the wall of the epidermal cyst.

Somewhat later, W. Lever and G. Shaumburg - Lever proposed their own classification of BCC, depending on the type of cells and the direction of their differentiation. The division into three groups has been preserved (differentiated, undifferentiated and special forms), poorly differentiated forms were excluded, the distribution of BCC variants related to one form or another was different, new tumor variants were added. In the group of differentiated tumors, the authors included cystic, adenoid, keratotic, granular, and adamantinoma-like variants; in the group of undifferentiated - solid, pigmented, scleroderma-like (morphea) and superficial.
E.S. Snarskaya proposes to keep the division of BCC into differentiated forms (basaliomas with elements of differentiation towards sweat, sebaceous glands or with elements of piloid differentiation) and undifferentiated (superficial, solid, morpheal-like, adenoid) and take into account the possibility of the presence of transitional forms.

A.N. Khlebnikova, on the basis of immunohistochemical methods of research, identified histological types of BCC depending on the form of cell growth, their function and the direction of differentiation without combining them into groups. These include superficial, multicentric, solid, adenoid (adenocystic), solid-adenoid, pigmented, scleroderma-like BCC, with sebaceous differentiation, with piloid differentiation (trichobasalioma), with squamous epithelial (epidermoid) differentiation, and a complex tumor (with the presence of different type differentiation).

Using the same method for diagnosing BCC, T. Wade and A. Ackerman proposed their own classification, which already includes 26 independent histological variants of basaliomas, without combining them into groups.
In accordance with the WHO clinical and morphological classification (Lyon, 2006), the following forms BCRC: superficial, nodular, (solid), micronodular, infiltrative, fibroepithelial, BCRC with adnexal differentiation, basal squamous cell (metatypical) cancer, keratotic, cystic, adenoid, morphea-like, infundibulocystic, pigmented and other rare variants.

However, in everyday practice, it is often necessary to confine ourselves to the clinical classification of BCC. According to T. Fitzpatrick, there are five clinical forms: tumor, ulcerative, scleroderma-like, superficial and pigmented. T.P. Pisklakova proposes to distinguish several more clinical forms of BCC: tumor with three varieties (exophytic, papillary and nodular), ulcerative, superficial, pigmented, sclerodermiform (self-scarring) and cystic. R. Raichev and V. Andreev identified two varieties of the surface form of BCRC - pagetoid and erythematous. Currently, the most commonly used classification is B.A. Berenbein, A.M. Vavilov and V.V. Dubensky, allocating superficial, tumor, ulcerative, pigmented and scleroderma-like forms of basalioma.

Features of the course of basal cell skin cancer

When characterizing BCC, the doctor must take into account several clinical criteria - primary or recurrent tumor growth, their number, shape, localization, combination with other tumors of the skin and internal organs. BCC recurrences are registered after removal of formations by various methods. In almost half (47.5%) of cases, relapses of BCC occurred after cryodestruction, in about 1/5 (18.4%) - after surgical excision of the tumor, less often - after laser destruction (11.8%), radiation therapy (10, 5%) and electrocoagulation (9.2%) and in a single case - after photodynamic therapy and when using combined methods of treatment.

According to the literature, the recurrence rate ranges from 10 to 29.2%. The most common (89%) recurrence occurred 5 years after completion of therapy. It is essential that relapses can be single (82%) and repeated (28%). Relapses should be distinguished from the appearance of new foci of proliferative growth in areas of healthy skin, which was observed in 10-20% of patients.

There are differences in the course of primary and recurrent BCC. Observation data of 429 patients with BCC of the eyelids in the ophthalmooncological center of the Chelyabinsk Regional Oncological Dispensary (1999-2005) indicate the predominance (2.9 times) of single relapses over multiple ones. In recurrent BCC compared with the primary process, multiple tumors were observed significantly 2.7 times more often (24.5% vs. 9%), 1.6 times more often they were recorded in patients with T2N0M0 stage (36.9% vs. %) and 2.2 times more often with T3-4N0M0 (24.6% versus 11%). The dependence of the frequency of relapses on the localization of the tumor was revealed. When it was located on the skin of the lower eyelid with the involvement of the intermarginal space, relapses were observed 1.9 times more often (27.7% vs. 15%) than with isolated localization only on the eyelid; 2.2 times more often (24.6% versus 12%) - with a widespread process involving two or more anatomical zones.

In the ulcerative form of BCC, relapses were recorded in 57% of cases, with aggressively growing growth - in 46.7% and mixed growth - in 26.6%.
The number of tumor foci in BCC can be single and multiple. The appearance of neoplasms, according to the definition of primary multiple tumors, can be recorded synchronously (simultaneously), metachronously (successively) and combined.

The incidence of multiple foci of BCC varies widely - from 1 to 21.4%. Differences in the frequency of development of multiple basaliomas can be explained from several positions. First of all, it is necessary to take into account the regional features of the ecological environment where patients with BCC live, and technogenically caused contact with various carcinogens. Secondly, the volume of material analyzed by various researchers. The longer the period of time covered by statistical analysis, the greater the likelihood of registering patients with multiple BCC. Thirdly, the presence of oncological alertness in patients, which is associated with the promotion of a healthy lifestyle among them. The sooner a patient turns to a specialist, the less likely the presence of multiple tumors.

Patients with solitary tumors predominated (85.6%) with a disease duration of up to a year. With a duration of the process of more than 12 years, the number of patients with single tumors decreased by 1.9 times (85.6% versus 45.2%), and with multiple tumors it increased by 3.8 times (14.4% versus 54.8% ). It was noted that with multiple basaliomas, superficial forms of BCC are more often recorded. At the same time, the frequency of their registration decreases as the duration of the disease increases.

It was revealed that the superficial form was much less common with the duration of the disease from a year to 12 years and more than 12 years compared with a prescription of up to a year. The incidence of the ulcerative form, on the contrary, increased by 2.6 times (from 1 year to 12 years) and 1.8 times (more than 12 years) compared with the incidence with a prescription of up to a year. Pigmented and scleroderma-like forms were detected in patients only with the duration of the process from 1 to 6 years. The solid form prevailed in patients with different duration of the process and ranged from 59.6% with the manifestation of the disease more than 12 years ago to 78.4% with the existence of the tumor for a year or less. It is significant that with an increase in the prescription of the disease, the number of patients with a combination of various forms tumors, from 4.6% (up to a year) to 26.2% (more than 12 years). The superficial form was more common with prescription up to a year and in patients with multiple lesions. Ulceration of the tumor occurred a year after its occurrence. Pigmented and scleroderma-like forms of BCC were formed when the duration of the disease was from 1 to 6 years.

Multiple basaliomas may be manifestations of genetic syndromes, in particular Gorlin-Goltz syndrome and xeroderma pigmentosum. In these cases, for the first time BCC may occur in childhood and adolescence.

Gorlin-Goltz syndrome (basal cell nevus syndrome, nevoid basal cell carcinoma syndrome) is a genetically determined disease, the main symptom of which is the multiple nature of BCC in combination with malformations of the nervous, endocrine systems, skeleton, eyes and other organs and tissues. In this syndrome, the presence of mutations in the PTCH gene located at the chromosomal locus 9q 22.3 q31 has been proven. In patients with Gorlin-Goltz syndrome, various malformations are revealed - palmoplantar depressions, odontogenic cysts, bone cysts, hypertelorism, keeled chest, rib splitting, congenital blindness, cataracts, etc. The frequency of the syndrome in the population is estimated as 1:56 000 and accounts for 0.5% of cases of all basapiomas, and 6.7% in the structure of multiple basapiomas.

At the same time, it should be remembered that multiple basaliomas do not always indicate the presence of Gorlin-Goltz syndrome. In addition to the absence of malformations of the nervous, endocrine systems, skeleton, eyes and other organs and tissues, there are other clinical criteria. The average age of patients with Gorlin-Goltz syndrome is 46.7 years, the average number of foci of proliferative growth is 25.1, which are localized in equal proportion on open and closed areas of the skin. The appearance of multiple basaliomas is the priority of patients with an average age of 63.9 years, the average number of foci is 3.7 with their predominant localization in open areas.
Multiple BCC may be a manifestation of a rare genetic syndrome, xeroderma pigmentosa. It occurs when each parent passes on to the child a recessive mutant gene responsible for reparative DNA synthesis. Pigmentary xeroderma is characterized by increased sensitivity of the skin to ultraviolet rays and ionizing radiation. The frequency of the disease among representatives of the European population is 1:250,000. Early symptoms that occur in the first three years of life are photodermatitis, photophobia, conjunctivitis. After 10-15 years, BCC develops, which can be multiple.

BCRC can be combined with malignant tumors of the skin and other organs. The frequency of such a clinical picture is almost the same in different regions of the Russian Federation: 7% - Chelyabinsk region, 10.7% - Middle Urals, 8% - Moscow region. More often, BCC precedes the development of and/or is combined with tumors of the colon.

BCC is localized mainly in open areas of the skin. Almost in 3/4 (72.7%) of patients, BCC occurs on the scalp, in a small part of patients (8.7%) on the skin of the trunk and in single observations on the lower extremities (2.3%), neck (1.7 %) and upper limbs (1%). In 13.6% of cases, tumors were located in two or more anatomical regions.

Quantitative assessment of tumor localizations was carried out. To do this, they were completely counted in 300 patients with BCC, taking into account the topics of the process. The association between the frequency of development and the average number of tumors in different parts of the skin, including different anatomical areas of the head, was revealed. The highest rates were registered in the head area (83.3% and 1.4, respectively). Both indicators were significantly lower in the localization of tumors in both open and closed areas of the skin of the trunk and extremities. At the same time, on the skin of the trunk (21.3% and 0.42) and lower extremities (6.3% and 0.07), the indicators were higher than in the assessment of the skin of the neck (3.7% and 0.04) and upper limbs(3.3% and 0.11). The data obtained indicate that insolation does not always play a leading role in the pathogenesis of the disease.

When analyzing the localization of BCC on the head, the rates of development and the average number of tumors were the highest in the nose (21.7% and 0.27), in the periorbital region (19.7% and 0.21), on the skin of the cheeks (15% and 0.22), auricle and external auditory canal (15.4% and 0.17), as well as the forehead (13.7% and 0.19). The indicators were slightly lower when assessing the skin of the scalp (11.7% and 0.16) and temples (10.7% and 0.12) and minimal when calculating the incidence and average number of tumors on the skin of the lips (2.7% and 0.03) and nasolabial folds (1.7% and 0.02).

Conclusion

Analysis of literature data on epidemiology, etiology and pathogenesis, classification and course of BCC allows the practitioner to expand the amount of knowledge on this issue and use them in their daily activities.

Skin cancer, like most cancers, is considered a polyetiological condition. And it is far from always possible to reliably find out the main trigger for the appearance of malignant cells. At the same time, the pathogenetic role of a number of exogenous and endogenous factors has been proven, and several precancerous diseases have been identified.

Skin cancer is a malignant neoplasm in the form of a tumor that develops as a result of atypical transformation of cells under the influence of subjective and objective factors. The disease is very dangerous because it affects the largest and most important organ of the human body.

By identifying cancer in its early stages and prescribing the right treatment, it can be permanently eliminated, preventing the return of the disease. In the case of the development of a severe, aggressive form, other organs of the human body are often affected, which leads to irreversible consequences, and sometimes even death.

It is extremely important to detect any kind of changes in the skin in a timely manner and consult a doctor for examination and treatment.

Skin cancer is a fairly common form of a malignant type of tumors, in which both women and men are affected almost equally, their age is mainly from 50 years or more, although the likelihood of developing the disease in one form or another in more than one form is not ruled out. young patients.

The area of ​​the lesion is, as a rule, areas of the skin that are open to one or another effect. The development of skin cancer is noted in 5% of the total number of cases of cancer as such.

The mechanism of the development of the disease

Exposure to UV radiation and other causative factors leads in most cases to direct damage to skin cells. At the same time, it is not the destruction of cell membranes that is pathogenetically important, but the effect on DNA.

Partial destruction of nucleic acids is the cause of mutations, which leads to secondary changes in membrane lipids and key protein molecules. Mostly basal epithelial cells are affected.

Various types of radiation and HPV have not only a mutagenic effect. They contribute to the appearance of relative immune deficiency.

This is due to the disappearance of dermal Langerhans cells and the irreversible destruction of some membrane antigens that normally activate lymphocytes. As a result, the work of the cellular link of immunity is disrupted, protective antitumor mechanisms are suppressed.

Immunodeficiency is combined with increased production of certain cytokines, which only exacerbates the situation. After all, these substances are responsible for cell apoptosis, regulate the processes of differentiation and proliferation.

The pathogenesis of melanoma has its own characteristics. Malignant degeneration of melanocytes is promoted not only by exposure to ultraviolet radiation, but also by hormonal changes.

Clinically significant for disrupting the processes of melanogenesis are changes in the levels of estrogens, androgens and melanostimulating hormone. That is why melanomas are more common in women of reproductive age.

Moreover, hormone replacement therapy, contraceptives and pregnancy can act as a provoking factor in them.

Another important factor the appearance of melanomas - mechanical damage to existing nevi. For example, tissue malignancy often begins after the removal of a mole, accidental injuries, and also in places where the skin is rubbed with the edges of clothing.

A malignant neoplasm originates from one or more pinkish spots that begin to peel off over time. This initial stage can last from one to two weeks to several years.

The main localization is the front part, dorsal shoulder and chest. It is here that the skin is the most delicate and susceptible to physiological changes in the body.

Skin cancer can form age spots, which grow in size, become convex, darken sharply to dark brown. It often occurs under the condition of the degeneration of moles into malignant neoplasms.

The tumor may also look like a simple wart.

CAUSES

Before the formation of a full-fledged malignant tumor, precancerous formations often appear, that is, precancerous diseases that have a high tendency to malignancy.

Precancers are divided into obligate and facultative. Obligate in almost 100% of cases degenerate into a malignant neoplasm. These types of tumors include:

• Bowen's disease;
• Erythroplakia Keira;
• Pigmentary xeroderma;
• Paget's disease.

For older men, the development of Bowen's disease is most characteristic. Precancer of this type is characterized by a violation of the integrity of the skin in any part of the body, however, it was noted that the surface of the body is more often affected.

Examination of the skin reveals a solitary plaque growing up to 10 cm in diameter. Hue varies in color from pale pink to purple.

The borders of the tumor are clear, moderately rising above the surface of the skin. During development, the surface of the formation may become crusted and eroded.

Bowen's disease is characterized by slow growth and a 100% chance of degeneration into squamous cell carcinoma. There is an increased risk of a combination of skin lesions and cancer of the internal organs.

A peculiar variation of Bowen's disease is Keyra's erythroplakia, the only difference is the predominant lesion of the mucous membranes. Compared to other tumors, it is considered a rare disease.

On visual inspection, it is a single plaque that has a scarlet hue with clear boundaries and edges rising above the skin surface. An essential sign indicating malignant degeneration is a change in the clarity of the boundaries, the appearance of erosion and ulceration.

With erythroplakia Queira, the ulcer is covered with fibrin or hemorrhagic crust.

Pigmentary xeroderma is a disease that manifests itself in childhood. It is characterized by hereditary transmission in an autosomal recessive manner. Pigmentary xeroderma appears as hypersensitivity to direct sunlight. The researchers identified three main periods of the course of the disease:

• Erythema and hyperpigmentation;
• Atrophic stage with the appearance of telangiectasias;
• Neoplasm stage.

The exact causes of the development of skin cancer cannot be established, but experts name a number of prerequisites that can provoke the disease:

• Exposure to the skin of chemical elements of a carcinogenic effect.
• Ionizing radiation.
• Frequent skin exposure to ultraviolet rays.
• Mechanical damage to tissues, scarring, which in the future can cause the formation of cancer cells and the development of oncology.
• A burn or radiation dermatitis can provoke the development of cancer.
• The degeneration of moles into malignant tumors.
• Heredity.
• The presence of precancerous diseases: nevi, skin pigmentation, skin ulcers, syphilis, tuberculosis, melanosis, etc. In case of incorrect or untimely treatment of these diseases, oncology of the skin can develop.

Causes are a condition or situation that is fertile ground for the development of a particular disease.

The causes of skin cancer are:

• influence of direct ultraviolet and ionizing radiation;
• prolonged exposure to the surface of the skin of chemical carcinogens, a similar effect is exerted by tobacco smoke;
• the genetic predisposition of the body to cancer, in particular to skin cancer;
• prolonged thermal effect on any area of ​​the skin;
• occupational hazards, for example, long-term work associated with skin contact with arsenic and tar;
• various skin diseases related to precancerous conditions, for example, chronic dermatitis, keratoacanthoma, senile dyskeratosis, a large number of warts, atheromas and papillomas, which are often injured;
• scars left after past illnesses, such as lupus, syphilis, trophic ulcers or burns.

The causes of skin cancer can be divided into external and internal.

External causes

There are many predisposing factors that can cause skin cancer.

• Excessive exposure to solar radiation and ultraviolet radiation. This factor especially dangerous for fair-skinned and fair-haired people.
• Professions that involve prolonged exposure to the sun.
• Chemical carcinogens (fuel oil, arsenic, oil and others).
• Prolonged thermal effect on specific areas of the skin. An example is "kangri cancer", it is common among the people of the mountainous regions of Nepal and India. This type of cancer develops on the skin of the abdomen, in those areas where pots of hot coal are placed for warming.
• Precancerous skin diseases (Bowen's disease, Paget's disease, xeroderma pigmentosa, Queyre's erythroplasia and benign neoplasms that are subject to constant traumatization).

Other causes of skin cancer include:

• Smoking.
• Contact radiation and chemotherapy. These methods, which were used to treat oncological diseases of other localization, can also cause skin cancer.
• Reduced immunity due to the influence of various factors. These factors may include: AIDS, the use of immunosuppressants and glucocorticoids after organ transplantation and in the treatment of autoimmune diseases.
• genetic predisposition.
• Sexual features. For example, melanomas, which occur mainly in women.

When considering the causes that provoke the development of skin cancer, there are two main types of factors that are directly related to the process. In particular, these are exogenous factors, as well as endogenous factors, we will consider them in more detail.

Otherwise, they can be defined as external factors. The most important of these factors can be distinguished ultraviolet radiation and the sun's rays in particular.

Remarkably, the development of squamous cell and basal cell carcinoma is provided by chronic damage to the skin obtained when exposed to UV radiation, but the development of melanoma occurs mainly as a result of periodic intense exposure to sunlight.

Moreover, in the latter version, even a single exposure is sufficient for this.

There are several predisposing causes that contribute to the appearance of malignant skin tumors, namely:

1. Long-term exposure of the skin to UV rays. This can be proved by the fact that residents of the southern regions suffer from skin cancer much more often than the northern ones.
2. Skin exposure to radiation.
3. Long-term thermal effect on the skin.
4. Chemical impact. For example, contact with soot, various resins, tar, arsenic.
5. Hereditary predisposition to skin cancer.
6. Frequent use of drugs that suppress the immune system (anticancer, corticosteroids.
7. Age over 50 years. At a younger age, malignant skin diseases appear less frequently, and skin cancer in children is diagnosed even less frequently (0.3% of all cancers).
8. Mechanical injuries of nevi, birthmarks, scars.

Why Skin Cancer Occurs

In addition to the above causes of skin cancer, there are also a number of diseases that are considered precancerous. Precancerous diseases are divided into obligate and facultative precancer. Obligate precancer is usually rare, slow developing diseases, which, however, one hundred percent turn into cancer. These include:

• xeroderma pigmentosa
• Paget's disease
• Bowen's disease
• erythroplasia of Queira

Optional precancers include all kinds of chronic skin diseases: dermatitis, inflammatory and dystrophic processes. Slow-healing wounds and skin ulcers are also considered facultative precancer.

Skin cancer, symptoms and signs in different forms have significant differences

Signs of skin cancer to look out for

• the presence of new moles or spots on the surface of the skin;
• dark red neoplasms that rise above the surface of the skin;
• wound surfaces that do not heal for a long time;
• moles that have been on the body for a long time began to change shape, color and size.

How does skin cancer manifest itself in each individual form?

CLASSIFICATION

There are several classifications according to which types of skin cancer can be distinguished. According to histological characteristics:

1. Basal cell carcinoma or basal cell carcinoma is the most common type of skin cancer. A more favorable type of cancer, because there is no tendency to infiltrative growth and metastasis;
2. Squamous cell carcinoma - often formed against the background of existing precancerous skin diseases. Oncoprocess is prone to germination of the thickness of the skin, early screening of metastases.

As such, there is no classification by localization. Cancer can affect almost all skin covering, including the skin of the lips, external genitalia, scrotum, anus.

The TNM classification includes four stages of skin cancer development, depending on the size of the tumor node, damage to regional nodes, and the presence of distant metastases.

Skin adenocarcinoma

Most often, skin cancer refers to all non-melanoma malignant neoplasms that originate from different layers of the dermis. Their classification is based on the histological structure. Melanoma (melanoblastoma) is often considered an almost independent form of carcinodermatosis, which is explained by the peculiarity of its origin and very high malignancy.

The main non-melanoma skin cancers are:

• Basal cell carcinoma (basalioma) is a tumor whose cells originate from the basal layer of the skin. It can be differentiated and undifferentiated.
• Squamous cell carcinoma (epithelioma, spinalioma) - occurs from the more superficial layers of the epidermis. It is subdivided into keratinized and non-keratinized forms.
• Tumors originating from the appendages of the skin (adenocarcinoma of the sweat glands, adenocarcinoma of the sebaceous glands, carcinoma of the appendages and hair follicles).
• Sarcoma, whose cells are of connective tissue origin.

In the diagnosis of each type of cancer, the WHO-recommended clinical TNM classification. It allows using numbers and letters to encrypt various characteristics tumor: its size and degree of invasion into surrounding tissues, signs of damage to regional lymph nodes and the presence of distant metastases. All this determines the stages of skin cancer.

Each type cancerous tumor have their own growth characteristics, which are additionally reflected in the final diagnosis. For example, basalioma is tumor (large and small nodular), ulcerative (in the form of a perforating or corroding ulcer) and superficially transitional.

Squamous cell carcinoma can also grow exophytically with the formation of papillary outgrowths or endophytically, that is, according to the type of ulcerative-infiltrative tumor. And melanoma is nodular and non-nodular (superficially common).

Other types of skin cancer are much less common and account for a fraction of a percent of all skin cancers. These can be tumors of the sweat and sebaceous glands (adenocarcinoma), tumors from the tissues that make up the follicles, skin metastases from other neoplasms.

To determine the type of tumor in these cases is possible only with the help of diagnostic procedures - MRI, computed tomography and biopsy.

Adenocarcinoma

Adenocarcinoma is a fairly rare type of skin cancer. It develops from glandular cells (sweat and sebaceous glands), grows slowly. It looks like a dense nodule of blue-violet color or a papule rising above the skin, it is formed in the axillary region, in the groin, under mammary glands among women.

The node is characterized by slow growth, but in some cases it can reach large sizes (8-10 cm). Germination deep into the skin tissue and metastasis is rare. After removal, a recurrence of the tumor in the same place is possible.

Verrucous carcinoma

Verrucous carcinoma is a rare type of skin cancer, a type of squamous cell carcinoma. Appears on the skin of the hands, looks like a wart, which makes it difficult to correctly diagnose in the early stages of the disease. However, these formations can bleed, which allows you to pay attention to them in time.

Since the skin is made up of cells that belong to a large number of tissues, there are significant differences in the tumors that affect them. Therefore, the concept of cancer in this case is very collective and defines all pathologies of a malignant nature.

However, experts distinguish the most common types, which include basilomas, melanomas, squamous cell formations, lymphomas, carcinomas, and Kaposi's sarcoma.

Squamous cell skin cancer

This type of pathological process on the skin has several synonyms, it can also be called squamous epithelioma or spinalioma. It occurs regardless of the area of ​​​​the body and can be located anywhere.

But the open parts of the body are most susceptible to this lesion, as well as underlip. Sometimes doctors find squamous cell carcinoma localized on the genitals.

This tumor is not selective to people by gender, but with regard to age, pensioners are more likely to suffer. As the reasons provoking its appearance, experts indicate scarring of tissues after burns or mechanical damage that is systematic.

Actinic keratosis, chronic dermatitis, lichen, lupus tuberculosis and other diseases can also provoke the appearance of squamous cell carcinoma.

Basalioma or basal cell carcinoma of the skin.

It got its name from the place of its "growth" - the basal layer of the epidermis. This tumor lacks the ability to metastasize and recur. Its migration is directed mainly into the depth of tissues with their inevitable destruction.

About 8 out of 10 of all skin cancers are of this type.

This is the least dangerous of all types of skin tumors. The exception is those cases when the basalioma is located on the face or auricles: in such circumstances, it can reach impressive volumes, affecting the nose, eyes, and damaging the brain. Most often occurs in older people.