DERMOID CYST OF THE PENIS

A dermoid cyst of the penis has not been documented previously in the literature. We report a young Caucasian who had an important swelling of the penis dating back several months. On examination a subcutaneous mass on the dorsal aspect of the shaft and prepuce was present. A cut aneous sinus discharging purulent material was also noted above the ma ss. Laboratory tests including serology for syphilis and bacteriologic examination were negative. An excisional biopsy revealed a nodular le sion in the subcutaneous tissue with tufts of hair emerging from the s urface. Histopathologic examination disclosed granulation tissue conta ining fragments of hair surrounded by granulomatous infiltrate. Serial sections allowed identification of a subcutaneous cyst. The wall was epidermoid and connected with several pilosebaceous units, A sinus tra ct lined by stratified squamous epithelium contiguous with the epiderm is was also noted. Clinical and histopathologic differential diagnoses me discussed. Evidence for a congenital origin of this condition is g iven.