Surgical aspects of subungual malignant melanomas. The Scottish Melanoma Group.

The incidence, treatment, and survival of subungual malignant melanomas in Scotland is reviewed from the Scottish Melanoma Group database. Between 1979 and 1989, 100 cases of subungual melanoma were identified (2.8% of all malignant melanomas in Scotland). The tumors tended to be locally advanced at the time of presentation (mean Breslow depth, 4.7 mm +/- 3.0 mm), and this is reflected in an overall 5-year survival of 41%. There was no difference in the survival of patients treated with local/proximal interphalangeal (PIP) joint amputation compared with those having more proximal amputations. Because nearly 70% of these tumors arose on the thumb or hallux, it is concluded that, provided adequate clearance could be obtained, less radical excision should be performed for these lesions to maintain maximum function.