Melanoma in black South Africans.

Abstract

There are distinct differences in malignant melanoma between black and white populations regarding the incidence, anatomical distribution, histogenetic types of melanoma, stage at presentation and prognosis. Several of these aspects have been addressed both by Lodder and colleagues in this issue of the journal and by other authors who have reported melanoma data from southern Africa. While there has been an inexorable increase worldwide in the incidence of cutaneous malignant melanoma among white population groups, the incidence of melanoma in black and Asian populations remains low compared with Western series. In a worldwide study evaluating 59 population-based carcinoma registries, Crombie reported a three-times greater melanoma incidence in white compared with black populations. Melanoma in the African-American population is reported to be 20 times less common than in American white population groups. In South Africa, the incidence of melanoma in the black population is 0.9 per 100 000, which is 15 times less than in the white population. In fair or light-skinned Celtic populations, more than 90% of melanomas occur in sun-exposed skin, whereas 60% of melanomas among Africans arise in non-sun-exposed skin, involving, in particular, plantar, palmar, subungual and mucosal surfaces. The volar and subungual areas are the most common anatomical sites of malignant melanoma in black populations, with 70% of melanomas found on the lower limb and 90% of melanomas on the leg occurring below the ankle.