A 43-year-old man presents with a 2.5 x 3 cm violaceous nodule with an erythematous rim on the patient's left upper back. The nodule has been present for "many years" but he says that it only recently became bothersome. The lesion started as a small "pimple" and grew in size over the years. The patient complains that now "it sticks out of my shirt" and he can't cover it up. Physical Examination The nodule appears to be composed of smaller nodules. It was firm to palpation but nontender.
The nodule seems to be fixed to the underlying tissue. A punch biopsy was performed. (Images attached) What is the diagnosis? *This case is from Docplexus Editorial Team for educative purpose only. Source: Medscape
