Melanoma - a tumor that develops from melanocytes, ie cells that produce skin pigment sunburn. For this reason, melanoma has a dark color. Melanocytes are of neuroectodermal origin. This means that they develop from progenitor cells of the nervous system. The main function of melanocytes is to protect the skin from excess solar radiation. Malignant melanoma - a very common disease. It is approximately 1% of all cases of cancer each year and develops in about four cases per 100 000 population. For melanoma, characterized by a high mortality rate - about one in three patients died. The reason for this phenomenon lies in the rapid growth and propensity for metastasis of the tumor. About a third of melanomas develop in the head and neck.
Risk factors for melanoma include excessive solar radiation (excess UV exposure, sunburn), the presence of a large number of "moles" moles trauma and genetic predisposition. Changes in hormonal status of the organism can both stimulate and inhibit the growth of melanoma. Not every type of nevi (birthmarks, moles) are equally prone to malignancy (malignization), moreover, melanoma can occur on a clean area of skin. Pigmented nevi are found in almost all people, but the most dangerous in terms of risk of malignancy are the epidermis, dermal nevi or border, which are characterized by almost black color with shades of gray or brown hair and no rough edges, not rising, or almost never rising above the surface skin.
For melanoma is characterized by:
Asymmetrical shape. The edges are irregular (sometimes toothed) shape, and often bleed
Change the color. Color melanoma is usually different from the classic tan the presence of gray, blue, pink and red shades and even white. It should be borne in mind that any change in color of moles should be cause for concern and requires investigation. Resizing. Typically, melanoma is characterized by the size of 6 mm in diameter.
Clinical manifestations of melanoma at an early stage may be absent. Also for melanoma is characterized by unpredictable behavior in terms of growth and metastasis. There are following types of melanoma:
Surface widespread melanoma. The most common type of melanoma usually develops from a nevus. It is characterized by slow growth for several years.
Nodular form. This is the second most common type of melanoma, which is a loose knot on the skin, prone to ulceration. It has a propensity for rapid growth.
Malignant lentigines (freckle of Hutchinson). The most often develops on the face of the elderly.
Peripheral lentigines. Not typical for people of the white race. The danger lies in the frequent development of melanoma on the sole, where it hard to see the emergence and growth.
Diagnosis of melanoma based on histological examination. At the same except for the actual microscopic structure of the estimated growth in all directions (the level of infestation), as Deep invasion is an unfavorable sign, indicating a high risk of metastatic melanoma, both through blood and the lymphatic system. We also use computed tomography, ELISA and other methods, etc. The need for additional research methods depends on the stage of the disease.
Treatment of melanoma primarily surgical. 1-2 stages of conducting a radical excision of melanoma with adequate capture of healthy tissue (0.5 to 2 cm around a melanoma). Sometimes it is necessary to selectively remove regional lymph nodes. Radiation therapy is rarely used, usually in combination with surgery and chemotherapy using a 4-stage disease. Chemotherapy is also used in the later stages, detection of metastases.
Prognosis depends on the nature of the growth stage of the disease, and even the location of the melanoma. In the first stage of the 5-year survival rate is 90% or more, while the fourth stage gives a 90% mortality. Equally disappointing prognosis of melanoma in the mucosa.
Prevention of melanoma is associated with risk factors for its development and is reduced to two basic principles: prevention of excessive sun exposure and injury prevention birthmarks.