title: Malignant degeneration in a presacral squamous cyst.
mesh_terms: D001943:Breast Neoplasms / Q000601:surgery; D002277:Carcinoma / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D004814:Epidermal Cyst / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000473:pathology; D012445:Sacrococcygeal Region