Melanoma – Watch for the Signs of Malignancy

Melanoma i/ˌmɛləˈnoʊmə/ (from Greek μέλας — melas, “dark”) is a malignant tumor of melanocytes.

Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel, oral cavity and the eye (see uveal melanoma).

Melanoma can originate in any part of the body that contains melanocytes.

Melanoma is less common than other skin cancers. However, it is much more dangerous if it is not found early. It causes the majority (75%) of deaths related to skin cancer. Worldwide, doctors diagnose about 160,000 new cases of melanoma yearly. It is more common in women than in men. In women, the most common site is the legs and melanomas in men are most common on the back. It is particularly common among Caucasians, especially northwestern Europeans living in sunny climates.

There are high rates of incidence in Oceania, Northern America, Europe, southern Africa, and Latin America, with a paradoxical decrease in southern Italy and Sicily. This geographic pattern reflects the primary cause, ultraviolet light (UV) exposure crossed with the amount of skin pigmentation in the population.
According to a WHO report, about 48,000 melanoma related deaths occur worldwide per year.

The treatment includes surgical removal of the tumor. If melanoma is found early, while it is still small and thin, and if it is completely removed, then the chance of cure is high. The likelihood of the melanoma coming back or spreading depends on how deeply it has gone into the layers of the skin. For melanomas that come back or spread, treatments include chemo- and immunotherapy, or radiation therapy.

A 57-year-old presented for medical attention with a “funny looking mole” on the lateral aspect of his left upper arm. The lesion was asymptomatic.

Key point: The eccentric placement of a darker spot within the overall lesion should raise suspicion for melanoma. The need for histologic examination is clear in such cases.

Treatment: The patient elected to have the entire lesion removed, rather than to undergo a biopsy. The macule proved to be a severely dysplastic junctional nevus. Because the lesion was already excised with a conservative margin of 5 mm clear skin, treatment was considered sufficient. The patient will receive periodic recall skin surface examinations.

Note: This lesion’s asymmetry is the most worrisome feature. The clear margin of 5 mm is identical of that recommended for melanoma-in-situ, so no additional surgery was suggested.

Consultive Live