title: Surgical Treatment of Primary Osteosarcoma of the Sacrum: A Case Series of 26 Patients.
abstract: METHODS
  Twenty-six patients were treated surgically for sacral osteosarcomas in our center. The oncological and functional results are analyzed.
  
  
  OBJECTIVE
  To describe the general characteristics and evaluate the outcome of surgical treatment of primary osteosarcoma of the sacrum.
  
  
  BACKGROUND
  A very few reports have addressed the technique and outcome of surgical treatment of primary sacral osteosarcoma. The survival rate of such cases is low.
  
  
  METHODS
  The clinical data of 26 patients treated surgically for sacral osteosarcomas from June 2000 to December 2013 at our hospital were retrospectively reviewed.
  
  
  RESULTS
  There were 15 males and 11 females with a median age of 28 years (range, 12-68 years). Distal metastasis occurred in 13 patients (50%), and local recurrence occurred in 10 patients (38.5%, including 6 patients with additional distal metastasis). The 1-year and 5-year survival rates were 92.3% and 38.7%, respectively. Adequate and inadequate surgical margins were obtained in 16 and 10 cases, respectively. Patients with adequate margins had a significantly lower recurrence rate (P = 0.015) and higher event-free survival rate (P = 0.04) than those with inadequate margins. However, the overall survival rate did not differ significantly between patients with adequate and inadequate margins (P = 0.22). Only seven cases showed a good response based on necrosis rate (>90%). Patients with a better response to chemotherapy had better event-free and overall survival rates.
  
  
  CONCLUSIONS
  Adequate surgical margins are achievable in most cases of sacral osteosarcomas. Adequate margins can significantly improve the recurrence rate and event-free survival rate compared with inadequate margins. However, sacrectomy is still a challenging surgical technique. Adequate margins are also difficult to obtain in sacrectomy. In addition, only a few patients had a good response to chemotherapy. These reasons lead to a low 5-year survival rate in primary sacral osteosarcoma patients.
  
  
  METHODS
  4.
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, China.
authors.forename: Yifei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.affiliation: Department of Pathology, Peking University People's Hospital, Beijing, China.
authors.forename: Danhua
authors.initials: D
authors.lastname: Shen
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Tang
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Ji
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Xu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000473:pathology / Q000601:surgery*; D002648:Child; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000601:surgery*; D012516:Osteosarcoma / Q000601:surgery*; D012445:Sacrococcygeal Region / Q000473:pathology; D012447:Sacrum / Q000473:pathology / Q000601:surgery*; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult