title: Surgery and radiotherapy for retroperitoneal and abdominal sarcoma: both necessary and sufficient.
abstract: OBJECTIVE
  To evaluate the effect of surgical resection and radiotherapy (RT) in retroperitoneal or abdominal sarcoma.
  
  
  METHODS
  Retrospective cohort.
  
  
  METHODS
  Surveillance, Epidemiology, and End Results, 1988-2005.
  
  
  METHODS
  Patients 18 years or older with initial diagnosis of primary retroperitoneal and nonvisceral abdominal sarcoma.
  
  
  METHODS
  Survival for 2 years after diagnosis. Kaplan-Meier survival was stratified based on surgery and RT status. Cox proportional hazards model was used to assess adjusted effects of surgery and RT on survival in patients with locoregional disease.
  
  
  RESULTS
  Of 1901 patients with locoregional disease, 1547 (81.8%) underwent resection; 447 (23.5%) received RT. Overall, patients who received both surgery and RT demonstrated improved survival compared with patients who underwent either therapy alone; patients undergoing monotherapy in turn had more favorable survival compared with patients who received neither therapy (P < .001, log rank). Cox analysis demonstrated that surgical resection (hazard ratio [HR], 0.24; 95% confidence interval [CI], 0.21-0.29; P < .001) and RT (0.78; 0.63-0.95; P = .01) independently predicted improved survival in locoregional disease only. In adjusted analyses stratified for American Joint Commission on Cancer (AJCC) stage, for stage I disease (n = 694), RT provided an additional benefit (HR, 0.49; 95% CI, 0.25-0.96; P = .04) independent of that from resection (0.35; 0.21-0.58; P < .001). For stage II/III (n = 552), resection remained protective (HR, 0.24; 95% CI, 0.18-0.32; P < .001); however, RT was no longer associated with a significant benefit (0.78; 0.58-1.06; P = .11).
  
  
  CONCLUSIONS
  In a national cohort of retroperitoneal and abdominal sarcomas, surgical resection was associated with significant survival benefits for AJCC disease stages I to III. Radiotherapy provided additional benefit for patients with stage I disease. Resection should be offered to reasonable surgical candidates with nonmetastatic retroperitoneal/abdominal sarcomas; radiotherapy may most benefit patients with early-stage disease.
authors.affiliation: Department of Medicine, University of Massachusetts Memorial Medical Center, Worcester, USA.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zhou
authors.forename: Theodore P
authors.initials: TP
authors.lastname: McDade
authors.forename: Jessica P
authors.initials: JP
authors.lastname: Simons
authors.forename: Sing Chau
authors.initials: SC
authors.lastname: Ng
authors.forename: Laura A
authors.initials: LA
authors.lastname: Lambert
authors.forename: Giles F
authors.initials: GF
authors.lastname: Whalen
authors.forename: Shimul A
authors.initials: SA
authors.lastname: Shah
authors.forename: Jennifer F
authors.initials: JF
authors.lastname: Tseng
mesh_terms: D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D009367:Neoplasm Staging; D018714:Radiotherapy, Adjuvant; D012186:Retroperitoneal Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D012189:Retrospective Studies; D018426:SEER Program; D012509:Sarcoma / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D015996:Survival Rate; D016896:Treatment Outcome