title: It's never too late: Smoking cessation after stereotactic body radiation therapy for non-small cell lung carcinoma improves overall survival.
abstract: OBJECTIVE
  As stereotactic body radiation therapy (SBRT) has emerged as a quick, effective, and well-tolerated treatment for early stage non-small cell lung carcinoma (NSCLC), it can be difficult to convince patients to quit smoking in follow-up. We evaluated whether there was a survival benefit to smoking cessation after SBRT.
  
  
  METHODS
  Patients with early-stage NSCLC treated from 2004 to 2013 who were still smoking tobacco at the time of SBRT were identified from a prospective institutional review board-approved registry. Peripheral tumors were treated to 54 Gy in 3 fractions and central tumors to 50 Gy in 5 fractions. Patients were reviewed for overall survival (OS) and disease progression. The log-rank and Cox regression tests were used to identify factors predictive of OS.
  
  
  RESULTS
  Thirty-two patients (27%) quit smoking after SBRT, and 87 (73%) continued smoking. Median follow-up was 22 months (range, 2-87). On multivariate analysis, smoking status (hazard ratio, 2.1; 95% confidence interval, 1.02-4.2; P = .045), increasing age-adjusted Charlson comorbidity score and larger tumor size were predictive of worse OS. The prior number of cigarette pack-years was not significant (P = .62). In a Kaplan-Meier comparison, smoking cessation after SBRT was associated with improved 2-year OS, 78% versus 69% (P = .014). There was no significant difference in 2-year progression-free survival (75% vs 55%, P = .23) or local control (97% vs 88%, P = .63).
  
  
  CONCLUSIONS
  OS is significantly improved in patients who stop smoking after SBRT for early-stage NSCLC, no matter their previous smoking history. Encouraging smoking cessation should be an important part of every posttreatment visit.
authors.affiliation: Department of Radiation Oncology, Siteman Cancer Center, Washington University in Saint Louis, St. Louis, Missouri.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Roach
authors.affiliation: Department of Radiation Oncology, Siteman Cancer Center, Washington University in Saint Louis, St. Louis, Missouri.
authors.forename: Sana
authors.initials: S
authors.lastname: Rehman
authors.affiliation: Department of Radiation Oncology, Siteman Cancer Center, Washington University in Saint Louis, St. Louis, Missouri.
authors.forename: Todd A
authors.initials: TA
authors.lastname: DeWees
authors.affiliation: Department of Radiation Oncology, Siteman Cancer Center, Washington University in Saint Louis, St. Louis, Missouri.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Abraham
authors.affiliation: Department of Radiation Oncology, Siteman Cancer Center, Washington University in Saint Louis, St. Louis, Missouri.
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Bradley
authors.affiliation: Department of Radiation Oncology, Siteman Cancer Center, Washington University in Saint Louis, St. Louis, Missouri. Electronic address: crobinson@radonc.wustl.edu.
authors.forename: Cliff G
authors.initials: CG
authors.lastname: Robinson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D011379:Prognosis; D011446:Prospective Studies; D016634:Radiosurgery / Q000401:mortality*; D011879:Radiotherapy Dosage; D016540:Smoking Cessation / Q000706:statistics & numerical data*; D015996:Survival Rate