title: Alveolar soft part sarcoma causing perianal abscess.
abstract: A 34-year-old woman presented with a perianal abscess that communicated with the vagina. There was a background of a one-year history of a conservatively treated, traumatic, paravaginal haematoma. Histology of the fistula tract showed alveolar soft part sarcoma and subsequent imaging  identified a large soft tissue mass in the pelvis with lung metastases. Alveolar soft part sarcoma is a rare soft tissue sarcoma of unknown cellular origin affecting predominantly young women, often in deep soft tissues and lower extremities.
authors.affiliation: North Bristol NHS Trust, Bristol, UK. niallsullivan@doctors.org.uk
authors.forename: Niall
authors.initials: N
authors.lastname: Sullivan
authors.forename: Tom
authors.initials: T
authors.lastname: McCulloch
authors.forename: David
authors.initials: D
authors.lastname: Leverton
mesh_terms: D000038:Abscess / Q000175:diagnosis / Q000209:etiology; D000328:Adult; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000556:secondary*; D010502:Perineum; D012003:Rectal Fistula / Q000209:etiology; D018234:Sarcoma, Alveolar Soft Part / Q000556:secondary*; D014624:Vaginal Fistula / Q000209:etiology