title: A comparison between accelerated hypofractionation and stereotactic ablative radiotherapy (SABR) for early-stage non-small cell lung cancer (NSCLC): Results of a propensity score-matched analysis.
abstract: OBJECTIVE
  Stereotactic ablative radiotherapy (SABR) has become standard for inoperable early-stage non-small cell lung cancer (NSCLC). However, there is no randomized evidence demonstrating benefit over more fractionated radiotherapy. We compared accelerated hypofractionation (AH) and SABR using a propensity score-matched analysis.
  
  
  METHODS
  From 1997-2007, 119 patients (T1-3N0M0 NSCLC) were treated with AH (48-60 Gy, 12-15 fractions). Prior to SABR, this represented our institutional standard. From 2008-2012, 192 patients (T1-3N0M0 NSCLC) were treated with SABR (48-52 Gy, 4-5 fractions). A total of 114 patients (57 per cohort) were matched (1:1 ratio, caliper: 0.10) using propensity scores.
  
  
  RESULTS
  Median follow-up (range) for the AH cohort was 36.3 (2.5-109.1) months, while that for the SABR group was 32.5 (0.3-62.6)months. Three-year overall survival (OS) and local control (LC) rates were 49.5% vs. 72.4% [p=0.024; hazard ratio (HR): 2.33 (1.28, 4.23), p=0.006] and 71.9% vs. 89.3% [p=0.077; HR: 5.56 (1.53, 20.2), p=0.009], respectively. On multivariable analysis, tumour diameter and PET staging were predictive for OS, while the only predictive factor for LC was treatment cohort.
  
  
  CONCLUSIONS
  OS and LC were improved with SABR, although OS is more closely related to non-treatment factors. This represents one of the few studies comparing AH to SABR for early-stage lung cancer.
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Chiang
authors.affiliation: Département de Radio-Oncologie, Centre Hospitalier Universitaire de Québec, Canada.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Thibault
authors.affiliation: Department of Radiation Oncology, London Regional Cancer Program, University of Western Ontario, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Warner
authors.affiliation: Department of Radiation Oncology, London Regional Cancer Program, University of Western Ontario, Canada.
authors.forename: George
authors.initials: G
authors.lastname: Rodrigues
authors.affiliation: Department of Radiation Oncology, London Regional Cancer Program, University of Western Ontario, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Palma
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Canada.
authors.forename: Hany
authors.initials: H
authors.lastname: Soliman
authors.affiliation: Centre for Cancer Research and Cell Biology, Queen's University Belfast, United Kingdom.
authors.forename: Suneil
authors.initials: S
authors.lastname: Jain
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Canada.
authors.forename: Ian
authors.initials: I
authors.lastname: Poon
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Canada. Electronic address: patrick.cheung@sunnybrook.ca.
authors.forename: Patrick
authors.initials: P
authors.lastname: Cheung
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D057216:Propensity Score; D016016:Proportional Hazards Models; D011446:Prospective Studies; D000069473:Radiation Dose Hypofractionation; D016634:Radiosurgery / Q000379:methods* / Q000401:mortality; D016896:Treatment Outcome
keywords: Accelerated hypofractionation; Lung cancer; Stereotactic radiotherapy