Subungual melanoma following a single injury.

Subungual melanoma is an uncommon disease. This paper presents eight cases where a subungual melanoma followed a single injury to the digit after an interval of between nine months and seven years (average 2.9 years). Although most injuries to the nail bed have no long term problems and subungual melanomata do arise in apparently normal nail beds, it is felt that there is increasing evidence that a direct causal relationship between the injury and the melanoma exists in some cases. This evidence includes case histories, statistical studies, the incidence of melanoma in coloured races and the distribution between the various digits.