title: Survival among Never-Smokers with Lung Cancer in the Cancer Care Outcomes Research and Surveillance Study.
abstract: BACKGROUND
  Differences in patient characteristics and outcomes have been observed among current, former, and never-smokers with lung cancer, but most prior studies included few never-smokers and were not prospective.
  
  
  OBJECTIVE
  We used data from a large, prospective study of lung cancer care and outcomes in the United States to compare characteristics of never-smokers and smokers with lung cancer and to examine survival among the never-smokers.
  
  
  METHODS
  Smoking status at diagnosis was determined by self-report and survival was determined from medical records and cancer registries, with follow-up through June 2010 or later. Cox regression was used to examine the association between smoking and survival, and to identify predictors of survival among never-smokers.
  
  
  RESULTS
  Among 3,410 patients with lung cancer diagnosed between September 1, 2003 and October 14, 2005 who completed a baseline patient survey, there were 274 never-smokers (8%), 1,612 former smokers (47%), 1,496 current smokers or smokers who quit recently (44%), and 28 with missing information about smoking status (<1%). Never-smokers appeared more likely than former and current/recent smokers to be female and of Asian or Hispanic race/ethnicity, and to have adenocarcinoma histology, fewer comorbidities, private insurance, and higher income and education. Compared with never-smokers, the adjusted hazard of death from any cause was 29% higher among former smokers (hazard ratio, 1.29; 95% confidence interval, 1.08-1.55), and 39% higher among current/recent smokers (hazard ratio, 1.39; 95% confidence interval, 1.16-1.67). Factors predicting worse overall survival among never-smokers included Hispanic ethnicity, severe comorbidity, undifferentiated histology, and regional or distant stage. Never-smoking Hispanics appeared more likely to have regional or advanced disease at diagnosis and less likely to undergo surgical resection, although these differences were not statistically significant.
  
  
  CONCLUSIONS
  Never-smokers with lung cancer are more likely than ever-smokers to be female, Asian or Hispanic, and more advantaged socioeconomically, suggesting possible etiologic differences in lung cancer by smoking status. Among never-smokers, Hispanics with lung cancer had worse survival than non-Hispanic whites.
authors.affiliation: 1 Department of Medicine, Stanford Cancer Institute, and.|2 Respiratory Diseases Department, University Hospital, Vandoeuvre-lès-Nancy, France.
authors.forename: Christelle
authors.initials: C
authors.lastname: Clément-Duchêne
authors.affiliation: 3 Department of Mathematics and Computer Science, College of the Holy Cross, Worcester, Massachusetts.
authors.forename: Shannon
authors.initials: S
authors.lastname: Stock
authors.affiliation: 4 Palo Alto Institute for Research and Education, Palo Alto, California.
authors.forename: Xiangyan
authors.initials: X
authors.lastname: Xu
authors.affiliation: 5 Division of Epidemiology, Department of Health Research and Policy, School of Medicine, Stanford University, Stanford, California.|6 Health Sciences Practice, Exponent, Inc., Menlo Park, California.
authors.forename: Ellen T
authors.initials: ET
authors.lastname: Chang
authors.affiliation: 5 Division of Epidemiology, Department of Health Research and Policy, School of Medicine, Stanford University, Stanford, California.|7 Cancer Prevention Institute of California, Fremont, California; and.
authors.forename: Scarlett Lin
authors.initials: SL
authors.lastname: Gomez
authors.affiliation: 5 Division of Epidemiology, Department of Health Research and Policy, School of Medicine, Stanford University, Stanford, California.|7 Cancer Prevention Institute of California, Fremont, California; and.
authors.forename: Dee W
authors.initials: DW
authors.lastname: West
authors.affiliation: 1 Department of Medicine, Stanford Cancer Institute, and.
authors.forename: Heather A
authors.initials: HA
authors.lastname: Wakelee
authors.affiliation: 8 Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, California.
authors.forename: Michael K
authors.identifier: http://orcid.org/0000-0001-6749-8315
authors.initials: MK
authors.lastname: Gould
mesh_terms: D000230:Adenocarcinoma / Q000208:ethnology / Q000401:mortality / Q000473:pathology; D000293:Adolescent; D000369:Aged, 80 and over; D005006:Ethnicity; D005260:Female; D006801:Humans; D007223:Infant; D008175:Lung Neoplasms / Q000208:ethnology / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology*; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology
keywords: Asian ethnicity; Hispanic ethnicity; cigarette smoking; lung cancer; survival