Melanoma Causes

Melanoma
Causes
Melanoma develops extensively in the area especially in regions with intense intermittent sun exposure (on the trunk in men, legs and back in women). Lentigo malignant melanoma is more common on exposed parts usually in the sun: face, neck and arms. The incidence is increasing in individuals with low melanic pigment, which live in warm areas near the equator, suggesting a causative role of ultraviolet radiation. Cancer is the result of complex interactions between different factors, both genetic and environmental. However, excessive exposure to ultraviolet radiation is the main risk factor for developing melanoma, regardless of whether radiation from the sun or from tanning machines.

About 40 -50% of melanomas develop from pigmented nevi, the rest of melanocytes in normal skin. Precancerous lesions include atypical nevi (dysplastic). Very rare cases of childhood melanomas develop from a giant congenital nevus. Although melanoma can occur during pregnancy, the pregnancy increases the risk that a mole to turn into a melanoma. In addition, warts frequently change their color and size during pregnancy.

Because a small fraction of cases of cutaneous melanoma occur by transforming pre-existing moles, removing all melanocytic nevi do not guarantee prevention of the occurrence of melanoma.

Melanoma
Causes
However, for individuals with many nevi (common or dysplastic) or with a family history of melanoma, skin self-examination is very important for early detection of skin cancer.