Subungual squamous cell carcinoma is a rare disease that has been frequently misdiagnosed as
benignity due to lack of awareness among doctors. The author reports a typical case of subungual squamous
cell carcinoma in a 49-year-old Thai farmer who presented with a 4-year history of chronic persistent
discharging ulcer at the nail bed of the left middle finger after experiencing a minor trauma to the hyponychium.
Initially, he was treated as benign infection but the condition did not improve. The nail bed was biopsied and
subungual squamous cell carcinoma was finally diagnosed. One small left epitrochlear lymph node and one
large left axillary lymph node were palpable. He underwent amputation of the neck of the middle phalanx of
the left middle finger, and biopsy of ipsilateral epitrochlear lymph node and dissection of the affected axillary
tissue. The histological examination confirmed the diagnosis of subungual squamous cell carcinoma with left
epitrochlear and axillary lymph node metastasis. Radiotherapy was planned.

Keywords: Carcinoma, Squamous cell, Nail diseases