[Subungual squamous cell carcinoma. An important differential diagnosis of subungual tumors].

A 63-year-old patient presented with a 12-month history of a subungual tumor on the right middle finger. The patient had had a similar lesion involving his left index finger 5 years ago, which was identified as a subungual squamous cell carcinoma. Ablation of the nail plate, the nailbed and the matrix was performed. Histopathology confirmed another subungual squamous cell carcinoma. The patient received a full thickness skin graft. Subungual squamous cell carcinomas are among the most frequently reported types of subungual malignancies. However, subungual squamous cell carcinomas arising in more than one digit have been reported only rarely. The cause of subungual squamous cell carcinoma has not been clearly identified, they has been associated with radiation, chronic infection, arsenic ingestion, HPV infection and trauma.