title: Association Between Radiation Dose and Outcomes With Postoperative Radiotherapy for N0-N1 Non-Small Cell Lung Cancer.
abstract: To review trends in the use of postoperative radiotherapy (PORT) in the modern era for N0-N1 margin-negative non-small cell lung cancer (NSCLC) following surgical resection and evaluate the association between PORT dose and overall survival.
  
  
  
  We performed a retrospective study of nonmetastatic stage II and III N0-N1 margin-negative NSCLC surgically treated patients within the National Cancer Data Base from 2003 to 2011. Cox proportional hazards regression was performed for multivariable analyses of overall survival and PORT dose. Radiation modalities included nonconformal beam radiation, 3-dimensional conformal radiation (3D-CRT), and intensity-modulated radiation therapy.
  
  
  
  We identified 2167 (6.7%) and 30,269 (93.3%) patients with surgically resected stage II or III N0-N1 margin-negative NSCLC who were treated with and without PORT, respectively. The proportion of patients treated with PORT (dose range, 45 to 74 Gy) decreased from 8.9% in 2003 to 2006 to 4.1% in 2010 to 2011. Among patients receiving PORT, the use of high-dose (60 to 74 Gy) PORT rose throughout the study period, starting at 34.8% in 2003 to 2006 and rising to 49.3% in 2010 to 2011.Overall, patients who received PORT had worse survival (hazards ratio=1.30; 95% confidence interval, 1.20-1.40) compared with those not receiving PORT. This association was unchanged when limited to patients receiving modern treatment with 3-CRT or intensity-modulated radiation therapy (hazards ratio=1.35; 95% confidence interval, 1.10-1.65).
  
  
  
  The use of PORT for N0-N1 margin-negative NSCLC decreased from 2003 to 2011. We found no evidence of benefit from PORT for resected N0-N1 margin-negative NSCLC, regardless of dose or technique. PORT should be approached with caution in this group of patients, regardless of radiotherapy technique.
authors.affiliation: Department of Therapeutic Radiology, Yale School of Medicine.|Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center at Yale.
authors.forename: Elyn H
authors.initials: EH
authors.lastname: Wang
authors.affiliation: Department of Therapeutic Radiology, Yale School of Medicine.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Corso
authors.affiliation: Department of Therapeutic Radiology, Yale School of Medicine.|Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center at Yale.
authors.forename: Henry S
authors.initials: HS
authors.lastname: Park
authors.affiliation: Department of Radiation Oncology, Harvard School of Medicine, Boston, MA.
authors.forename: Aileen B
authors.initials: AB
authors.lastname: Chen
authors.affiliation: Department of Therapeutic Radiology, Yale School of Medicine.
authors.forename: Lynn D
authors.initials: LD
authors.lastname: Wilson
authors.affiliation: Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center at Yale.|Department of Thoracic Surgery, Yale School of Medicine, New Haven, CT.
authors.forename: Anthony W
authors.initials: AW
authors.lastname: Kim
authors.affiliation: Department of Therapeutic Radiology, Yale School of Medicine.|Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center at Yale.
authors.forename: Roy H
authors.initials: RH
authors.lastname: Decker
authors.affiliation: Department of Therapeutic Radiology, Yale School of Medicine.|Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center at Yale.
authors.forename: James B
authors.initials: JB
authors.lastname: Yu
mesh_terms: D000046:Academic Medical Centers; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality* / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D015331:Cohort Studies; D016208:Databases, Factual; D018572:Disease-Free Survival; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D008297:Male; D000072662:Margins of Excision; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D011013:Pneumonectomy / Q000379:methods; D011379:Prognosis; D016016:Proportional Hazards Models; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome