title: Comparing Preoperative With Postoperative Stereotactic Radiosurgery for Resectable Brain Metastases: A Multi-institutional Analysis.
abstract: Stereotactic radiosurgery (SRS) is an increasingly common modality used with surgery for resectable brain metastases (BM).
  
  
  
  To present a multi-institutional retrospective comparison of outcomes and toxicities of preoperative SRS (Pre-SRS) and postoperative SRS (Post-SRS).
  
  
  
  We reviewed the records of patients who underwent resection of BM and either Pre-SRS or Post-SRS alone between 2005 and 2013 at 2 institutions. Pre-SRS used a dose-reduction strategy based on tumor size, with planned resection within 48 hours. Cumulative incidence with competing risks was used to determine estimated rates.
  
  
  
  A total of 180 patients underwent surgical resection for 189 BM: 66 (36.7%) underwent Pre-SRS and 114 (63.3%) underwent Post-SRS. Baseline patient characteristics were balanced except for higher rates of performance status 0 (62.1% vs 28.9%, P < .001) and primary breast cancer (27.2% vs 10.5%, P = .010) for Pre-SRS. Pre-SRS had lower median planning target volume margin (0 mm vs 2 mm) and peripheral dose (14.5 Gy vs 18 Gy), but similar gross tumor volume (8.3 mL vs 9.2 mL, P = .85). The median imaging follow-up period was 24.6 months for alive patients. Multivariable analyses revealed no difference between groups for overall survival (P = .1), local recurrence (P = .24), and distant brain recurrence (P = .75). Post-SRS was associated with significantly higher rates of leptomeningeal disease (2 years: 16.6% vs 3.2%, P = .010) and symptomatic radiation necrosis (2 years: 16.4% vs 4.9%, P = .010).
  
  
  
  Pre-SRS and Post-SRS for resected BM provide similarly favorable rates of local recurrence, distant brain recurrence, and overall survival, but with significantly lower rates of symptomatic radiation necrosis and leptomeningeal disease in the Pre-SRS cohort. A prospective clinical trial comparing these treatment approaches is warranted.
  
  
  
  BM, brain metastasesCI, confidence intervalCTV, clinical target volumeDBR, distant brain recurrenceGTV, gross tumor volumeLC, local controlLMD, leptomeningeal diseaseLR, local recurrenceMVA, multivariable analysisOS, overall survivalPost-SRS, postoperative stereotactic radiosurgeryPre-SRS, preoperative stereotactic radiosurgeryPTV, planning target volumeRN, radiation necrosisSRN, symptomatic radiation necrosisSRS, stereotactic radiosurgeryWBRT, whole-brain radiation therapy.
authors.affiliation: *Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, Georgia; ‡Southeast Radiation Oncology Group, Levine Cancer Institute, Carolinas Healthcare System, Charlotte, North Carolina; §Carolina Neurosurgery and Spine Associates, Levine Cancer Institute, Charlotte, North Carolina; ¶Biostatistics and Bioinformatics Shared Resource, Winship Cancer Institute, Emory University, Atlanta, Georgia; ‖Department of Neurological Surgery, Emory University, Atlanta, Georgia.
authors.forename: Kirtesh R
authors.initials: KR
authors.lastname: Patel
authors.forename: Stuart H
authors.initials: SH
authors.lastname: Burri
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Asher
authors.forename: Ian R
authors.initials: IR
authors.lastname: Crocker
authors.forename: Robert W
authors.initials: RW
authors.lastname: Fraser
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.forename: Zhengjia
authors.initials: Z
authors.lastname: Chen
authors.forename: Shravan
authors.initials: S
authors.lastname: Kandula
authors.forename: Jim
authors.initials: J
authors.lastname: Zhong
authors.forename: Robert H
authors.initials: RH
authors.lastname: Press
authors.forename: Jeffery J
authors.initials: JJ
authors.lastname: Olson
authors.forename: Nelson M
authors.initials: NM
authors.lastname: Oyesiku
authors.forename: Scott D
authors.initials: SD
authors.lastname: Wait
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Curran
authors.forename: Hui-Kuo G
authors.initials: HK
authors.lastname: Shu
authors.forename: Roshan S
authors.initials: RS
authors.lastname: Prabhu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000532:radiotherapy* / Q000556:secondary / Q000601:surgery*; D001943:Breast Neoplasms / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology; D011182:Postoperative Care; D011300:Preoperative Care; D016634:Radiosurgery; D012189:Retrospective Studies