Squamous cell carcinoma arising in an epidermal cyst.
D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D004814:Epidermal Cyst / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012878:Skin Neoplasms / Q000473:pathology*