Skin cancer — the malignant tumoral disease of skin resulting from atipichesky transformation of its cages and differing in considerable polymorphism. Allocate 4 main types of cancer of skin: planocellular, basal and cellular, the adenocarcinoma and a melanoma, each of which in turn has several clinical forms. Diagnosis of cancer of skin includes survey of all integument, Dermoscopy and ultrasonography of the changed sites of skin and tumoral knots, a siaskopiya of pigmentary new growths, survey and a palpation of lymph nodes, cytology of dabs prints and a histologic research. Cancer therapy of skin consists in its fuller removal, performing radiation therapy, photodynamic influence and chemotherapy.
Among total number of malignant tumors cancer of skin makes about 10%. Now the dermatology notes a tendency to growth of incidence with an average annual gain of 4,4%. Most often cancer of skin develops at people of advanced age, is not dependent on their floor. The white-skinned people, persons living in conditions of the increased insolation (tropical countries, mountain areas) are most predisposed to developing of a disease and it is long staying in the open air.
In the general structure of cancer of skin of 11-25% it is the share of a planocellular form of cancer and about 60-75% for basal and cellular cancer. As development of planocellular and basal and cellular cancer of skin comes from cells of epidermis, these diseases also carry to malignant epitelioma.
Causes of cancer of skin
Among the reasons causing malignant regeneration of cells of skin excess ultra-violet radiation is on the first place. It proves the fact that nearly 90% of cases of cancer of skin develop on the open parts of the body (the person, a neck) which are most often exposed to radiation. And for people with light skin influence of UV rays is the most dangerous.
Developing of cancer of skin can be provoked by impact on it of various chemicals possessing cancerogenic action: tar, lubricants, arsenic, particles of tobacco smoke. The radioactive and thermal factors operating on skin can lead to emergence of cancer. So, cancer of skin can develop on the place of a burn or as a complication of beam dermatitis. The frequent travmatization of hems or birthmarks can become the reason of their malignant transformation with developing of cancer of skin.
Contributing to emergence of cancer of skin can be hereditary features of an organism that causes family cases. Besides, some skin diseases have ability over time to be exposed to malignant regeneration in skin cancer. Such diseases belong to precancer states. Their list includes Keyr's eritroplaziya, Bowen's disease, a pigmentary xeroderma, a leukoplakia, a senile keratoma, a skin horn, Dyubreylya, a melanomoopasny nevus (a difficult pigmentary nevus, a blue nevus, a huge nevus, Ott's nevus) and chronic inflammatory damages of skin (trophic ulcers, tuberculosis, syphilis, hard currency, etc.).
Classification of cancer of skin
Allocate the following forms of cancer of skin:
- Planocellular cancer of skin (skvamozno-cellular carcinoma) — develops from flat cages of a blanket of epidermis.
- Basal and cellular cancer of skin (bazaliom) — arises at atipichesky regeneration of the basal cells of epidermis having rounded shape and located under a layer of flat cages.
- Skin adenocarcinoma — the rare malignant tumor developing from grease or sweat glands.
- Melanoma — the skin cancer arising from its pigmentary cages — melanotsit. Considering a number of features of a melanoma, many modern writers identify the concept "skin cancer" only with non-melanoma cancer.
At non-melanoma cancer of skin apply the international TNM classification to assessment of prevalence and a stage of process.
T — prevalence of primary tumor
- TH — cannot estimate a tumor because of a lack of data
- THAT is a tumor is not defined.
- Tis — cancer on the place (a preinvazivny carcinoma).
- TI — the size of a tumor is up to 2 cm.
- T2 — the size of a tumor is up to 5 cm.
- TZ — the size of a tumor is more than 5 cm.
- T4 — cancer of skin sprouts in underlying deep fabrics: muscles, cartilages or bones.
N — a condition of lymph nodes
- NX — cannot estimate a condition of regionarny lymph nodes because of a lack of data.
- N0 — signs of metastasises in regionarny lymph nodes are not revealed.
- N1 — is available metastatic damage of regionarny lymph nodes.
M — existence of metastasis
- MX — a lack of data on existence of the remote metastasises.
- MO — signs of the remote metastasises are not revealed.
- M1 — existence of the remote metastasises of cancer of skin.
Assessment of degree of a differentiation of tumor cells is made within gistopatologichesky classification of cancer of skin.
- GX — there is no opportunity to define differentiation degree.
- G1 — a high differentiation of tumor cells.
- G2 — an average differentiation of tumor cells.
- G3 — a low differentiation of tumor cells.
- G4 — undifferentiated cancer of skin.
Skin cancer symptoms
Planocellular cancer of skin is characterized by rapid growth and distribution both on the surface of skin, and in depth. Germination of a tumor in the fabrics located under skin (muscular, bone, cartilaginous) or accession of an inflammation is followed by emergence of a pain syndrome. Planocellular cancer of skin can be shown in the form of an ulcer, a plaque or knot.
The ulcer option of planocellular cancer of skin has an appearance of the crateriform ulcer surrounded as the roller, the dense raised and abruptly breaking edges. The ulcer has the uneven bottom covered with crusts of the dried-up serous and bloody exudate. From it quite unpleasant smell proceeds. The plaque of planocellular cancer of skin differs in bright red coloring, a dense consistence and a hilly surface. It often bleeds and quickly increases in sizes.
The Krupnobugristy surface of knot at planocellular cancer of skin makes it similar to a cauliflower or a mushroom. The big density, bright red or brown coloring of tumoral knot is characteristic. Its surface can erozirovatsya or .
Basal and cellular cancer of skin has more good-quality and slow current, than planocellular. Only in the started cases it sprouts the subject fabrics and causes morbidity. Metastasis, as a rule, is absent. Basal and cellular cancer of skin differs in big polymorphism. It can be presented nodular , the warty, pro-butting, cicatricial and atrophic, pigmentary, nodulyarny, sklerodermiformny, flat superficial and "tyurbanny" forms. The beginning of the majority of clinical options of a bazalioma occurs from education on skin of a single small small knot. In certain cases new growths can have multiple character.
The skin adenocarcinoma most often arises on the sites rich with sweat and sebaceous glands. These are axillary hollows, inguinal area, folds under mammary glands, etc. The adenocarcinoma begins with formation of the isolated knot or a papule of the small sizes. This seldom found type of cancer of skin is characterized by slow growth. Only in certain cases the adenocarcinoma can reach the big sizes (about 8 cm in the diameter) and to sprout muscles and fastion.
The melanoma in most cases represents the pigmented tumor having black, brown or gray coloring. However cases and the depigmented melanomas are known. In the course of growth of melanomny cancer of skin allocate a horizontal and vertical phase. Its clinical options are presented by a lentigo-melanoma, the superficial extending melanoma and a nodal melanoma.
Skin cancer complications
Skin cancer, extending in depth of fabrics, causes their destruction. Considering frequent localization of cancer of face skin, process can affect ears, eyes, okolonosny bosoms, a brain that leads to loss of hearing and sight, development of sinusitis and meningitis of a malignant origin, defeat of the vital structures of a brain up to a lethal outcome.
Metastasis of cancer of skin happens first of all on lymphatic vessels to development of malignant damage of regionarny lymph nodes (cervical, axillary, inguinal). At the same time consolidation and increase in the affected lymph nodes, their painlessness and mobility when probing comes to light. Over time there is an accustoming to drinking of a lymph node to the fabrics surrounding it therefore it loses mobility. There is a morbidity. Then the lymph node breaks up with formation of ulcer defect of the skin located over it.
Distribution of cancer cells with current of blood leads to formation of the secondary tumoral centers in internals with development of lung cancer, a stomach, bone, liver, a tumor of a brain, a breast cancer, cancer of a kidney, a malignant tumor of an adrenal gland.
Diagnosis of cancer of skin
Patients with suspicion of cancer of skin have to be consulted dermatoonkology. The doctor performs inspection of education and other sites of skin, a palpation of regionarny lymph nodes, Dermoscopy. Determination of depth of germination of a tumor and prevalence of process can be made by means of ultrasonography. For pigmentary educations the siaskopiya is in addition shown.
It is final can confirm or disprove the diagnosis of cancer of skin only cytologic and a histologic research. The cytologic research is made by microscopy of specially painted dabs prints made from a surface of cancer ulcers or erosion. Histologic diagnosis of cancer of skin is carried out on the material received after removal of a new growth or by a skin biopsy. If integrity of skin over tumoral knot is not broken, then capture of biopsiyny material is carried out by a punktsionny method. According to indications make a biopsy of a lymph node. The histology reveals existence of atipichesky cages, establishes their origin (flat, basal, melanotsita, ferruterous) and differentiation degree.
When diagnosing cancer of skin in certain cases it is necessary to exclude its secondary nature, that is existence of primary tumor of internals. Especially it concerns skin adenocarcinomas. Ultrasonography of abdominal organs, a X-ray analysis of lungs, KT of kidneys, contrast urography, a stsintigrafiya of a skeleton, brain MPT and KT and so forth is for this purpose carried out. The same inspections are necessary in diagnostics of the remote metastasises or cases of deep germination of cancer of skin.
Cancer therapy of skin
The choice of a way of cancer therapy of skin is defined according to its type, prevalence of process, degree of a differentiation of cancer cells. Also localization of cancer of skin and age of the patient is considered.
The main objective in cancer therapy of skin is its radical removal. Most often it is carried out by surgical excision of pathologically changed fabrics. Operation is performed with capture probably of healthy fabrics on 1-2 cm. Microscopic intraoperative inspection of a regional area of the deleted education allows to carry out operation with the minimum capture of healthy fabrics during the fullest removal of all tumor cells of cancer of skin. Excision of cancer of skin can be carried out by means of the neodymium or carbon dioxide laser that reduces bleeding during operation and yields good cosmetic result.
Electrothermic coagulation, curettage or removal by the laser can be applied to tumors, small by the size (to 1-2 cm) at insignificant germination of cancer of skin in surrounding fabrics. When carrying out electrothermic coagulation the recommended capture of healthy fabrics makes 5-10 mm. The superficial high-differentiated and low-invasive forms of cancer of skin can be exposed to cryodestruction with capture of healthy fabrics on 2-2,5 cm. As cryodestruction does not leave an opportunity for carrying out histologic studying of remote material, it can be carried out only after a preliminary biopsy with confirmation of small distribution and a high differentiation of a tumor.
The skin cancer occupying the insignificant square can be effectively cured by means of a short-distance rentgenterapiya. Radiation by an electron beam is applied to treatment of superficial, but large formations of cancer of skin. Radiation therapy after removal of tumoral education is shown to patients with high risk of metastasis and in case of a skin cancer recurrence. Radiation therapy is also applied to suppression of metastasises and as a palliative method in case of inoperable cancer of skin.
Application of photodynamic therapy of cancer of skin at which radiation is carried out against the background of introduction of photosensitizers is possible. At a bazalioma the local chemotherapy cytostatics gives positive effect.
Prevention of cancer of skin
The preventive actions directed to the prevention of cancer of skin consist in protection of skin against influence adverse chemical, radiation, ultra-violet, traumatic, thermal, etc. influences. It is necessary to avoid open sunshine, especially in the period of the greatest solar activity, to use various sun-protection means. The workers of chemical industry and faces tied with radioactive radiation need to follow safety rules and to use protective equipment.
Observation of the patients having precancer diseases of skin is important. Regular surveys of the dermatologist or a dermatoonkolog in such cases are directed to timely identification of signs of regeneration of a disease in skin cancer. The prevention of transformation of a melanomoopasny nevus in cancer of skin consists in a right choice of medical tactics and a way of their removal.
Forecast of cancer of skin
Lethality indicators at cancer of skin are one of the lowest in comparison in other oncological diseases. The forecast in many respects depends on a type of cancer of skin and degree of a differentiation of tumor cells. Basal and cellular cancer of skin has more good-quality current without metastasis. At adequately carried out timely treatment of planocellular cancer of skin 5 summer survival of patients make 95%. The most adverse forecast at patients with a melanoma at which 5 summer survival make only 50%.