title: Radiotherapy and extent of surgical resection in retroperitoneal soft-tissue sarcoma: multi-institutional analysis of 261 patients.
abstract: OBJECTIVE
  To examine the impact of adjuvant radiotherapy (RT) and surgical technique on survival in retroperitoneal soft-tissue sarcoma.
  
  
  METHODS
  A retrospective analysis was conducted using the National Oncology Database, a proprietary database of aggregated tumor registries owned by IMPAC(R) Medical Systems (Sunnyvale, CA). Patients who received definitive surgery with negative or microscopic-positive margins were included. Multivariate analysis was performed using the Cox proportional hazards model. Survival curves were estimated by the Kaplan-Meier method and were compared for statistical significance (P < 0.05) using the log-rank test.
  
  
  RESULTS
  Two hundred sixty-one patients met inclusion criteria. The median follow-up was 59 months (range 0.2-186 months). The 5-year cause-specific survival (CSS) and local failure-free survival (LFFS) were 73% and 66%, respectively. Grade, margin status, and histology were independent predictors for CSS (P < 0.05). Adjuvant RT was associated with a significant improvement in LFFS over surgery alone (hazard ratio = 0.42, 95% confidence interval 0.21-0.86, P < 0.05). Patients receiving simple excision and RT had a 5-year LFFS of 88%, significantly higher than wide resection with or without RT (log-rank, P < 0.05).
  
  
  CONCLUSIONS
  Adjuvant RT is associated with a lower risk of local relapse compared to surgery alone. The impact of surgical technique on adjuvant RT efficacy warrants further study.
authors.affiliation: Department of Radiation Oncology, Huntsman Cancer Hospital, University of Utah, Salt Lake City, Utah 84112, USA. sagus.sampath@hci.utah.edu
authors.forename: Sagus
authors.initials: S
authors.lastname: Sampath
authors.forename: Ying J
authors.initials: YJ
authors.lastname: Hitchcock
authors.forename: Dennis C
authors.initials: DC
authors.lastname: Shrieve
authors.forename: R Lor
authors.initials: RL
authors.lastname: Randall
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Schultheiss
authors.forename: Jeffrey Y C
authors.initials: JY
authors.lastname: Wong
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D012186:Retroperitoneal Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D012189:Retrospective Studies; D012509:Sarcoma / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D017211:Treatment Failure