title: Thermal ablation matches sublobar resection outcomes in older patients with early-stage non-small cell lung cancer.
abstract: OBJECTIVE
  To compare survival outcomes of sublobar resection and thermal ablation for early-stage non-small cell lung cancer (NSCLC) in older patients.
  
  
  METHODS
  SEER-Medicare linked data for patients with a diagnosis of lung cancer from 2007-2009 were used. Patients ≥ 65 years old with stage IA or IB NSCLC who were treated with sublobar resection or thermal ablation were identified. Primary outcome was overall survival (OS), and secondary outcome was lung cancer-specific survival (LCSS). Demographic and clinical variables were compared. Unadjusted OS and LCSS curves were estimated using the Kaplan-Meier method, and multivariate analysis was performed using the Cox model. OS and LCSS curves for propensity score matched groups were also compared.
  
  
  RESULTS
  The final unmatched study population comprised 1,897 patients. Patients who underwent sublobar resection were significantly younger (P = .006) and significantly less likely to have a comorbidity index > 1 (P = .036), a diagnosis of chronic obstructive pulmonary disease (P = .017), or adjuvant radiation therapy (P < .0001) compared with patients treated with thermal ablation. Unadjusted survival curves of unmatched groups demonstrated significantly better OS (P = .028) and LCSS (P = .0006) in the resection group. Multivariate Cox model adjusting for demographic and clinical variables found no significant difference in OS between the treatment groups (P = .555); a difference in LCSS (hazard ratio = 1.185, P = .026) persisted. Survival curves for matched groups found no significant difference in OS (P = .695) or LCSS (P = .819) between treatment groups.
  
  
  CONCLUSIONS
  After controlling for selection bias, this study found no difference in OS between patients treated with sublobar resection and thermal ablation.
authors.affiliation: Department of Radiology, University of Washington Medical Center, 1959 NE Pacific Street, 357115, Seattle, WA 98195. Electronic address: shakwan@uw.edu.
authors.forename: Sharon W
authors.initials: SW
authors.lastname: Kwan
authors.affiliation: Department of Radiology, University Hospitals Case Medical Center, Cleveland, Ohio.
authors.forename: Kelly E
authors.initials: KE
authors.lastname: Mortell
authors.affiliation: Department of Radiology, Weill Cornell Medical Center, New York, New York.
authors.forename: Adam D
authors.initials: AD
authors.lastname: Talenfeld
authors.affiliation: Departments of Radiology, William S. Middleton Memorial Veterans Administration Hospital and University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Brunner
mesh_terms: D055011:Ablation Techniques / Q000009:adverse effects / Q000401:mortality; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D016009:Chi-Square Distribution; D018572:Disease-Free Survival; D005260:Female; D006358:Hot Temperature; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008297:Male; D015999:Multivariate Analysis; D011013:Pneumonectomy / Q000009:adverse effects / Q000401:mortality; D057216:Propensity Score; D016016:Proportional Hazards Models; D012307:Risk Factors; D018426:SEER Program; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States
keywords: COPD; HR; LCSS; NSCLC; OS; SEER; Surveillance, Epidemiology and End Results program; chronic obstructive pulmonary disease; hazard ratio; lung cancer–specific survival; non–small cell lung cancer; overall survival