title: Evidence supporting contemporary post-operative radiation therapy (PORT) using linear accelerators in N2 lung cancer.
abstract: OBJECTIVE
  Post-operative radiotherapy (PORT) treatment for lung cancer declined since a meta-analysis failed to show benefit in patients with N2 disease. Because several included studies employed outmoded radiation planning and delivery techniques, we sought to determine whether PORT with modern technology benefits patients with N2 disease.
  
  
  METHODS
  We conducted searches of the published literature. For inclusion, studies must have included patients with stage III-N2 lung cancer treated with PORT using only linear accelerators, used a control group that did not receive PORT, and reported outcome data for overall survival (OS). Prospective and retrospective analyses were included. Exclusion criteria were the use of cobalt devices or orthovoltage radiation.
  
  
  RESULTS
  Data were evaluated with random-effects models. Three prospective and eight retrospective studies were included. The PORT and no-PORT groups included 1368 and 1360 patients, respectively. The PORT group had significantly improved OS over the no-PORT group (hazard ratio [HR] = 0.77, 95% confidence interval [CI] 0.62-0.96, P = 0.020). Locoregional recurrence-free survival (LRFS) in 10 studies for which data was available was also improved in the PORT group (HR = 0.51, CI 0.41-0.65, P < 0.001).
  
  
  CONCLUSIONS
  PORT was associated with significantly lower risk of death and locoregional recurrence in patients with N2 lung cancer. Our study was limited by lack of access to individual patient data, which would have enabled more detailed analyses. Regardless, data thus far suggest PORT may be associated with a survival benefit. Given a lack of large-scale prospective data, clinical trials evaluating PORT with modern technology are warranted.
authors.affiliation: Stich Radiation Center, New York Presbyterian Hospital/Weill Cornell Medical Center, 525 East 68th Street, New York, NY 10065, United States.
authors.forename: Suchit H
authors.initials: SH
authors.lastname: Patel
authors.affiliation: Division of Biostatistics and Epidemiology, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10021, United States.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Stich Radiation Center, New York Presbyterian Hospital/Weill Cornell Medical Center, 525 East 68th Street, New York, NY 10065, United States.
authors.forename: A Gabriella
authors.initials: AG
authors.lastname: Wernicke
authors.affiliation: Stich Radiation Center, New York Presbyterian Hospital/Weill Cornell Medical Center, 525 East 68th Street, New York, NY 10065, United States.
authors.forename: Dattatreyudu
authors.initials: D
authors.lastname: Nori
authors.affiliation: Stich Radiation Center, New York Presbyterian Hospital/Weill Cornell Medical Center, 525 East 68th Street, New York, NY 10065, United States.
authors.forename: K S C
authors.initials: KS
authors.lastname: Chao
authors.affiliation: Stich Radiation Center, New York Presbyterian Hospital/Weill Cornell Medical Center, 525 East 68th Street, New York, NY 10065, United States. Electronic address: bup9001@med.cornell.edu.
authors.forename: Bhupesh
authors.initials: B
authors.lastname: Parashar
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000532:radiotherapy*; D018572:Disease-Free Survival; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D010315:Particle Accelerators; D016016:Proportional Hazards Models; D018714:Radiotherapy, Adjuvant / Q000295:instrumentation; D016896:Treatment Outcome
keywords: Lung; Meta-analysis; N2; PORT; Radiation; Survival