title: Squamous cell carcinoma arising in a pilonidal sinus presenting with the formation of an abscess.
mesh_terms: D000038:Abscess / Q000209:etiology*; D002294:Carcinoma, Squamous Cell / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010864:Pilonidal Sinus / Q000150:complications*; D012878:Skin Neoplasms / Q000150:complications*