title: Role of post-operative radiation boost for soft tissue sarcomas with positive margins following pre-operative radiation and surgery.
abstract: OBJECTIVE
  The role of a radiation therapy (RT) boost for positive margins following pre-operative RT and surgery in extremity soft tissue sarcomas (STS) is unclear. We assessed the contribution of a boost to local control (LC), disease-free survival (DFS), and overall survival (OS).
  
  
  METHODS
  We identified 67 patients treated from 1987 to 2011 with pre-operative RT and surgery with positive margin(s). Select patients received a boost delivered as peri-operative Iridium-192 brachytherapy (BRT), intra-operative electrons (IORT), or post-operative external beam RT (EBRT).
  
  
  RESULTS
  Ten patients received no RT boost, 10 received a BRT or IORT boost, and 47 received an EBRT boost. Five-year LC rates for no boost, BRT/IORT boost, and EBRT boost were 100%, 78%, and 71% (P = 0.5). On multivariate analysis, there were no significant predictors for LC. Variables associated with improved DFS rates were single positive margin (P = 0.007) and low tumor grade (P = 0.03). Tumor size <5 cm (P = 0.003), low grade (P = 0.001), and boost (P = 0.02) were associated with longer survival.
  
  
  CONCLUSIONS
  We did not identify a LC advantage for an RT boost. Given the unidentified selection factors for delivery of boost and its potential toxicities, its role in this setting remains unproven.
authors.affiliation: Department of Radiation Oncology, Boston, Massachusetts; Massachusetts General Hospital, Boston, Massachusetts; University of Southern California Keck School of Medicine, Los Angeles, California.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Pan
authors.forename: Saveli I
authors.initials: SI
authors.lastname: Goldberg
authors.forename: Yen-Lin
authors.initials: YL
authors.lastname: Chen
authors.forename: Christine
authors.initials: C
authors.lastname: Giraud
authors.forename: Jason L
authors.initials: JL
authors.lastname: Hornick
authors.forename: Gunnlaugur P
authors.initials: GP
authors.lastname: Nielsen
authors.forename: Francis J
authors.initials: FJ
authors.lastname: Hornicek
authors.forename: Chandrajit P
authors.initials: CP
authors.lastname: Raut
authors.forename: Thomas F
authors.initials: TF
authors.lastname: DeLaney
authors.forename: Elizabeth H
authors.initials: EH
authors.lastname: Baldini
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy; D003131:Combined Modality Therapy; D005121:Extremities / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D018365:Neoplasm, Residual / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D011182:Postoperative Care; D011379:Prognosis; D011879:Radiotherapy Dosage; D012509:Sarcoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D015996:Survival Rate; D055815:Young Adult
keywords: extremity; local control; positive margin; post-operative boost; radiation therapy; sarcoma