Pilomatricoma mimicking small round cell tumor on fine needle aspiration cytology: a case report.

Background: Pilomatricoma, a benign skin adnexal tumor, frequently leads to false positive diagnosis cytologically. We report a rapidly growing nodular swelling misdiagnosed as round cell tumor cytologically and found to be pilomatricoma histopathologically.

Case: A 32-year-old man presented with a rapidly growing, mobile nodule on his left arm for 4 months with fixed, shiny overlying skin.