Skin cancer
Skin cancer (melanoma and epithelial) cancers are common.
The two main types of skin cancer are:
* The epithelial cancers with 80 to 800 new cases per year per 100 000 population by country;
* Malignant melanomas with 4 to 6 new cases per 100 000 people in France each year.
Skin carcinomas
(spino epitheliomatous cancer and basal cell)
What is it?
The epitheliomatous cancer (or carcinoma) skin cancer of the superficial layer of the skin: the epidermis.
This includes:
* Basal cell carcinomas evolving purely local;
*The spinocellular epitheliomatous cancer can be invasive and metastatic.
These skin cancers are most common in Caucasian people.
They thrive in subjects at risk who can be identified, enabling prevention and early detection.
The prognosis depends on early diagnosis.
Populations at risk
Environmental factors are paramount.
The sun is the main enemy of the skin. The sun exposure are all the more harmful they are prolonged, intense and involve the patient skin (phototype 1, II or III).
Factors are also toxic.
The arsenic poisoning of occupational origin is (viticulture etc.), Drug (liqueur Fowler formerly used in the treatment of psoriasis) or very rarely food.
Handling of toxic substances such as polycyclic aromatic hydrocarbons, tars, can cause skin carcinoma.
Smoking in combination with the sun plays an important role in the development of cancers of the lower lip.
Drug causes (iatrogenic) are possible:
Some skin cancers induced by radiotherapy. This therapy is vital in the treatment of many cancers, is dropped against certain indications: angioma, tinea, dermatitis chronic …
The puvathérapie is a widely used treatment for psoriasis. It involves taking an oral psoralen (méladinine) with exposure to UVA. The long-term consequences of such treatment, especially if prolonged, are at increased risk of squamous cell carcinoma.
Immunosuppressive treatments (particularly AZT) also increases the risk of skin cancer.
Some states are cutaneous risk factors: scars, burns, ulcers, chronic inflammatory skin diseases etc.
Family of rare skin diseases are also risk factors: xeroderma pigmentosum, épidermodysplasie verruciformis, basal cell nævomatose, albinism …
Basal cell carcinomas
The tumor derives from the basal cells of the epidermis.
Several factors contributed to their occurrence:
* Exposure to sunlight and ionizing radiation;
* All treatments with arsenic;
* The great age and Caucasian;
* The existence of precancerous skin lesions such as solar keratoses: small dry red scaly plaques in areas exposed to sunlight.
The occurrence of these cancers is usually in areas exposed to sunlight. You must be careful when the skin shows signs of photo-induced aging. These signs are especially clear in the face, chest, back of hands and forearms. The skin is thin, irregularly pigmented, wrinkled, dry, covered by telangiectasias and sometimes papules or yellowish patches corresponding to areas of elastosis. The patient or doctor should be concerned before any damage persistent papular, erythematous (red) or color of normal skin, crusted or ulcerated.
Clinical aspects vary. Pearl épithéliomateuse is typical. They are small translucent grains of 1 to 5 mm in diameter, Opaline, firm, found at the periphery of the lesion.
The skin biopsy allows diagnosis histologically.
The spontaneous evolution is slowly extensive surface without invasion of surrounding tissues or metastasis. Under treatment, the evolution is favorable. Local recurrence may occur if treatment is poorly led.
Early treatment is based on the complete surgical excision of the lesion or, for small tumors, destruction, liquid nitrogen or laser.
Regular monitoring is required (every 6 months or every year) because of the risk of developing other cutaneous carcinomas.
Epitheliomatous spinocellular
These rare tumors derived from keratinocytes of the epidermis.
Clinically, the lesion can take different aspects, bud, or ulceration saignotante benign lesion. Biopsy is necessary in any doubt.
The extension is local, regional (lymph nodes) and general (metastases).
The treatment is wide surgical excision combined if necessary to the lymph node. Radiotherapy and chemotherapy have their indications.
The causes are similar to those of basal cell carcinomas but additional factors are possible:
* Malignant degeneration of old scars of burns, for example, or of chronic wounds such as leg ulcer;
* Degeneration of a keratosis or Bowen’s disease.
The actinic keratoses are precancerous skin lesions. These lesions are very frequent and almost all the elderly light-skinned who lived and worked in the sunshine.
They are often associated with signs of chronic sun exposure (wrinkles, elastosis, telangiectasia, pigmentation).
They are presented as plaques, variable size, erythematous and keratotic. Their surface is rough to the touch feature. Some of these keratoses are hyperkeratotic (cutaneous horn). Where there is a seepage, erosion or erythema marked a transformation in spino-cellular epithelioma should be suspected.
The actinic keratoses should be distinguished from seborrheic warts.
Methods of destruction of actinic keratoses are: electro-curettage, cryotherapy (dry ice, liquid nitrogen), local chemotherapy by 5-fluorouracil (5FU), tretinoin (cream with vitamin A acid), interferon alpha, retinoids by General …
Bowen’s disease is rare. It takes the form of a plate of limited érythémato-scaly few mm to several cm can sit anywhere. Eczema, psoriasis are sometimes mentioned, but the fixity of the lesion requires histological examination. The risk of transformation into squamous cell carcinoma is important.
Treatment is urgent and is based on surgical excision or electrocoagulation.
The prognosis depends on early diagnosis.
Prevention
Some preventive measures are simple: photoprotection, treatment of actinic keratoses etc.