An annoying mass of the nail bed.

A 56-year-old patient was referred to our unit for a bothersome, mass located under the left thumb nail, of 3 years duration. On clinical examination, the nail plate appeared detached with an underlying bleeding mass; lymphadenopathy was not detected on axillary palpation. Onychoscopy showed a wide area of onycholysis with a homogeneous, mainly violaceous blotchy area beneath. A punch biopsy was performed from the nodule, histopathologic examination of which showed proliferation of atypical epithelial cells infiltrating the nail bed stroma