Subungual squamous cell carcinoma.

Twelve patients with subungual squamous cell carcinoma were treated at Memorial Sloan-Kettering Cancer Center during a 27-year period. To our knowledge, only 58 cases are reported in the literature. Trauma and chronic infection were predisposing factors in some of the cases, and radiation therapy was a substantive predisposing factor in our series. Disarticulation of the distal phalanx proved effective in most patients.