Subungual squamous cell carcinoma masquerading as a melanotic macule.

Subungual squamous cell carcinoma is a rare condition. Diagnosis is often delayed because it presents with minimal nail changes and mimics a number of benign nail conditions. We report a 43-year-old Chinese man who presented with a three-year history of an indolent melanotic macule of the fingernail. Histology from a punch biopsy revealed a well-differentiated squamous cell carcinoma. Wide local excision with full thickness skin grafting was performed. Physicians should have a high index of clinical suspicion as early nail biopsy and prompt tumour clearance can preserve joint function.