OBJECTIVE: To examine incidence and survival patterns of acral lentiginous melanoma (ALM) in the United States. DESIGN: Population-based registry study. We used the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute to evaluate data from 17 population-based cancer registries from 1986 to 2005. PARTICIPANTS: A total 1413 subjects with histologically confirmed cases of ALM. Main Outcome Measure Incidence and survival patterns of patients with ALM. RESULTS: The age-adjusted incidence rate of ALM overall was 1.8 per million person-years. The proportion of ALM among all melanoma subtypes was greatest in blacks (36%). Acral lentiginous melanoma had 5- and 10-year melanoma-specific survival rates of 80.3% and 67.5%, respectively, which were less than those for all cutaneous malignant melanomas overall (91.3% and 87.5%, respectively; P < .001). The ALM 5- and 10-year melanoma-specific survival rates were highest in non-Hispanic whites (82.6% and 69.4%), intermediate in blacks (77.2% and 71.5%), and lowest in Hispanic whites (72.8% and 57.3%) and Asian/Pacific Islanders (70.2% and 54.1%). Acral lentiginous melanoma thickness and stage correlated with survival according to sex and in the different racial groups. CONCLUSIONS: Population-based data showed that ALM is a rare melanoma subtype, although its proportion among all melanomas is higher in people of color. It is associated with a worse prognosis than cutaneous malignant melanoma overall. Hispanic whites and Asian/Pacific Islanders have worse survival rates than other groups, and factors such as increased tumor thickness and more advanced stage at presentation are the most likely explanations.
Bradford et al. (Wed,) studied this question.