Atypical pyoderma gangrenosum of the dorsal hand mimicking squamous cell carcinoma.

We describe a rare case of atypical pyoderma gangrenosum of the dorsal hand in a patient who presented with the histopathologic diagnosis of squamous cell carcinoma (SCC). Atypical pyoderma gangrenosum is a rare variant of pyoderma gangrenosum that occurs on the upper extremities, presenting as a cutaneous ulcer. The correct treatment is nonsurgical, and surgical intervention often results in trauma-induced expansion of lesions. Pyoderma gangrenosum, most commonly mistaken for infection, has resulted in amputation. Histologic and clinical presentation 1 month after onset of symptoms in the patient reported here mimicked SCC. Awareness by hand surgeons of the possible histologic misdiagnosis of SCC at an early stage in the disease evolution and a high index of suspicion in the face of biopsy-proven SCC may prevent unnecessary digit amputation.