title: Buttock soft tissue sarcoma: clinical features, treatment, and prognosis.
abstract: BACKGROUND
  Primary buttock soft tissue sarcomas in adults are common entities that have been infrequently reported (three clinical series and isolated case reports). We present our experience of buttock sarcomas to better characterize and define the natural history of this condition.
  
  
  METHODS
  Buttock tumors occurring in adults (>16 years) between January 1990 and January 2002 were identified from the Royal Marsden Hospital's Sarcoma Unit prospective database.
  
  
  RESULTS
  Seventy-three buttock sarcomas were evaluated and treated at the Royal Marsden Hospital during this period. Liposarcoma (n = 19), leiomyosarcoma (n = 13), and synovial sarcoma (n = 9) were the most frequent histological types. There were 8 T1 and 61 T2 tumors, and size was not available in 4 patients. Most tumors (n = 64) were located deep to the deep fascia. There were 15 grade 1, 20 grade 2, and 37 grade 3 tumors, and grade was not available in 1 patient. There were 29 tumors contained within the gluteus maximus. Wide excision was performed in 50 patients. Local recurrence and distant metastasis occurred in 15 and 35 patients with a median time of 18 and 8 months, respectively. The rate of local recurrence at 2 years was 20.9% (SE, 6.8%). The 2-year overall and disease-free survival rates were 64.1% (SE, 6.7%) and 48.5% (SE, 6.4%), respectively.
  
  
  CONCLUSIONS
  Buttock sarcomas present special surgical difficulties because of proximity of the sciatic nerve and the ability of tumors at this site to extend into the pelvis and perineum. Size and grade of the tumor were independent predictors for disease-free and overall survival.
authors.affiliation: Sarcoma and Melanoma Unit, Royal Marsden National Health Service Trust, South Kensington, London, United Kingdom. kbelranwala@hotmail.com
authors.forename: K A
authors.initials: KA
authors.lastname: Behranwala
authors.forename: P
authors.initials: P
authors.lastname: Barry
authors.forename: R
authors.initials: R
authors.lastname: A'Hern
authors.forename: J M
authors.initials: JM
authors.lastname: Thomas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002081:Buttocks / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D012509:Sarcoma / Q000473:pathology* / Q000628:therapy; D012983:Soft Tissue Neoplasms / Q000473:pathology* / Q000628:therapy; D016019:Survival Analysis