Prognostic factors and survival in acral lentiginous melanoma.

BACKGROUND: Acral lentiginous melanoma (ALM) is a rare melanoma subtype that disproportionately afflicts people of colour. ALMs have a worse prognosis than other melanoma subtypes; this has been attributed to aggressive biological behaviour, more advanced stage at presentation and possible disparities in access to health care.

OBJECTIVES: To examine, using comprehensive patient data and long-term follow-up information in a well-characterized cohort, how patient, tumour and clinical management variables impact overall and melanoma-specific survival.

METHODS: We characterized a consecutive cohort of 123 ALMs diagnosed from 1987 to 2013 and analysed predictors of overall and melanoma-specific survival for their association with survival.

RESULTS: Univariate hazard ratios and 95% confidence intervals using Cox regression models showed that increased Breslow depth, presence of ulceration, receipt of radiation, chemo- and vaccine therapy were associated with worse melanoma-specific survival. Notably, nonwhite race/ethnicity was not associated with worse overall or melanoma-specific survival. Multivariate modelling adjusting for patient, tumour and management variables revealed Breslow depth > 2 mm and disease extent as significantly associated with poor melanoma-specific survival.

CONCLUSIONS: Melanoma-specific mortality among patients with ALM is associated with increased tumour thickness and more advanced stage at presentation, but not with race/ethnicity. Advanced tumour features at presentation and access to care may account for less favourable survival outcomes reported among nonwhite patients.