title: Preoperative radiation therapy combined with radical surgical resection is associated with a lower rate of local recurrence when treating unifocal, primary retroperitoneal liposarcoma.
abstract: OBJECTIVE
  Local recurrence (LR) is the primary cause of death in patients with retroperitoneal liposarcoma (RP-LPS). The purpose of this study was to evaluate if the addition of preoperative radiation therapy (XRT) to radical resection for RP-LPS at a single institution was associated with improved LR.
  
  
  METHODS
  This retrospective analysis included patients with unifocal, primary RP-LPS who underwent complete R0/R1 resection at a single institution between 1991 and 2013. Multiple patient, tumor, and surgeon characteristics were tested to evaluate their association to LR (recurrence in the retroperitoneal space). We used competing risk hazards regression to evaluate the effect of preoperative XRT on the probability of LR.
  
  
  RESULTS
  There were 41 patients with liposarcoma histology whose tumors included entirely well-differentiated (N = 13), de-differentiated components (n = 26), myxoid (n = 1), and NOS (n = 1). Preoperative XRT was significantly associated with a lower probability of LR (HR 0.11, 95%CI 0.01-0.91, P = 0.04) and a higher 5-year local recurrence-free survival (95.6%, 95%CI 72.4-99.4%, vs. 75.0%, 95%CI 40.8-91.2%; P = 0.0213), but not with 5-year distant recurrence-free survival or disease-specific survival.
  
  
  CONCLUSIONS
  Preoperative XRT combined with complete R0/R1 resection for unifocal, primary RP-LPS was associated with improved LR and it should be considered in the multimodality treatment of RP-LPS. J. Surg. Oncol. 2016;114:814-820. © 2016 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Surgery, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: George
authors.initials: G
authors.lastname: Molina
authors.affiliation: Division of Surgical Oncology, Virginia Commonwealth University School of Medicine, Richmond, Virginia.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Hull
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Yen-Lin
authors.initials: YL
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: DeLaney
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Karen
authors.initials: K
authors.lastname: De Amorim Bernstein
authors.affiliation: Division of Hematology and Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Edwin
authors.initials: E
authors.lastname: Choy
authors.affiliation: Division of Hematology and Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Gregory
authors.initials: G
authors.lastname: Cote
authors.affiliation: Division of Hematology and Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: David C
authors.initials: DC
authors.lastname: Harmon
authors.affiliation: Department of Surgery, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: John T
authors.initials: JT
authors.lastname: Mullen
authors.affiliation: Department of Surgery, Massachusetts General Hospital, Boston, Massachusetts. abhaynes@mgh.harvard.edu.
authors.forename: Alex B
authors.initials: AB
authors.lastname: Haynes
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016208:Databases, Factual; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008080:Liposarcoma / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology / Q000517:prevention & control*; D018714:Radiotherapy, Adjuvant; D012186:Retroperitoneal Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
keywords: local; neoplasm recurrence; radiotherapy; retroperitoneal liposarcoma