title: Comparison of long-term survival outcomes between stereotactic body radiotherapy and sublobar resection for stage I non-small-cell lung cancer in patients at high risk for lobectomy: A propensity score matching analysis.
abstract: BACKGROUND
  The aim of this study was to perform a survival comparison between stereotactic body radiotherapy (SBRT) and sublobar resection (SLR) in patients with stage I non-small-cell lung cancer (NSCLC) at high risk for lobectomy.
  
  
  METHODS
  All patients who underwent SBRT or SLR because of medical comorbidities for clinical stage I NSCLC were reviewed retrospectively. Propensity score matching (PSM) was performed to reduce selection bias between SLR and SBRT patients based on age, gender, performance status, tumour diameter, forced expiratory volume in 1 second (FEV1) and Charlson comorbidity index (CCI).
  
  
  RESULTS
  One hundred and fifteen patients who underwent SBRT and 65 SLR were enrolled. The median potential follow-up periods for SBRT and SLR were 6.7 and 5.3 years, respectively. No treatment-related deaths were observed. Before PSM, the 5-year overall survival (OS) was 40.3% and 60.5% for SBRT and SLR, respectively (P=0.008). PSM identified 53 patients from each treatment group with similar characteristics: a median age of 76 years, a performance status of 0-1, a median tumour diameter of ∼20 mm, a median FEV1 of ∼1.8L and a median CCI of 1. The difference in OS became insignificant between the matched pairs (40.4% and 55.6% at 5 years with SBRT and SLR; P=0.124). The cumulative incidence of cause-specific death was comparable between groups (35.3% and 30.3% at 5 years, P=0.427).
  
  
  CONCLUSIONS
  SBRT can be an alternative treatment option to SLR for patients who cannot tolerate lobectomy because of medical comorbidities.
authors.affiliation: Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Japan. Electronic address: ymatsuo@kuhp.kyoto-u.ac.jp.
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Matsuo
authors.affiliation: Department of Thoracic Surgery, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Fengshi
authors.initials: F
authors.lastname: Chen
authors.affiliation: Department of Thoracic Surgery, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Hamaji
authors.affiliation: Department of Biomedical Statistics and Bioinformatics, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kawaguchi
authors.affiliation: Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Nami
authors.initials: N
authors.lastname: Ueki
authors.affiliation: Department of Radiation Oncology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Nagata
authors.affiliation: Department of Thoracic Surgery, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Sonobe
authors.affiliation: Department of Biomedical Statistics and Bioinformatics, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Morita
authors.affiliation: Department of Thoracic Surgery, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Date
authors.affiliation: Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hiraoka
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality; D057216:Propensity Score; D016634:Radiosurgery / Q000401:mortality*; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Minimally invasive surgery; Non-small cell lung cancer; Propensity score; Stereotactic body radiotherapy; Treatment outcome