Melanoma, malignant

The most serious of the 3 types of skin cancer, the other 2 being basal cell carcinoma and squamous cell carcinoma. Malignant melanoma is a tumour of melanocytes, the cells that produce melanin, and is due to long-term exposure to strong sunlight. There are an increasing number of new cases and deaths in the UK each year from this skin cancer. Tumours usually develop on exposed skin but may occur anywhere on the body. A melanoma usually grows from an existing mole, which may enlarge, become lumpy, bleed or crust over, change colour, develop an irregular edge, turn into a scab, or become itchy. Occasionally, a melanoma develops in normal skin. The tumour often spreads to other parts of the body. Diagnosis is by a skin biopsy and the melanoma is removed surgically. Radiotherapy or anticancer drugs may also be necessary.