title: Predictors of survival for younger patients less than 50 years of age with non-small cell lung cancer (NSCLC): a California Cancer Registry analysis.
abstract: BACKGROUND
  Non-small cell lung cancer (NSCLC) is uncommonly diagnosed in patients younger than 50 years of age. We analyzed the California Cancer Registry (CCR) to describe epidemiologic characteristics and outcomes in this patient subset and to identify factors prognostic for cause-specific survival (CSS).
  
  
  METHODS
  Patients diagnosed with NSCLC between 1/1/98 through 12/31/09 and reported to the (CCR) as of October 2011 were included. The primary outcome measure was CSS. Cox regression models were used to evaluate predictors of CSS in young patients with NSCLC, adjusted for potential confounders. Interaction analysis was performed between age groups (<50 vs. ≥50) and specific demographic and tumor covariates.
  
  
  RESULTS
  We identified 132,671 lung cancer cases, of which 114,451 (86.3%) had NSCLC. Of these, 6389 (5.6%) were<50 years of age (median, 46 years). The most common histology was adenocarcinoma (3697, 57.9%). Most patients had stage III (1522, 23.8%) or IV (3655, 57.2%) disease. Fewer young patients were diagnosed in recent years (n, % of total NSCLC population of that era): 1998-2001 (2355, 6.0), 2002-2005 (2182, 5.7), and 2006-2009 (1852, 5.0), P<0.001. Multivariate analysis showed that age <50 years was an independent predictor of improved CSS (HR 0.827, P<0.001). Significant predictors of better CSS in patients <50 years included female sex, Asian or Hispanic ethnicity, lower stage, later year of diagnosis, and higher socioeconomic status, among others. Adenocarcinoma histology was not associated with improved CSS in this patient subset (HR 0.987, P=0.78). Interaction analysis revealed that Hispanic race and bronchioloalveolar histology had differential CSS outcomes dependent on age group.
  
  
  CONCLUSIONS
  This large registry study found that age <50 years is an independent predictor of improved CSS. Variables prognostic for CSS differed somewhat from those in older patients.
authors.affiliation: Davis Senior High School, Davis, CA, United States.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Lara
authors.affiliation: Division of Hematology Oncology, and University of California Davis Comprehensive Cancer Center, UC Davis School of Medicine Sacramento, CA, United States.
authors.forename: Ann
authors.initials: A
authors.lastname: Brunson
authors.affiliation: Division of Hematology Oncology, and University of California Davis Comprehensive Cancer Center, UC Davis School of Medicine Sacramento, CA, United States.
authors.forename: Ted
authors.initials: T
authors.lastname: Wun
authors.affiliation: Division of Hematology Oncology, and University of California Davis Comprehensive Cancer Center, UC Davis School of Medicine Sacramento, CA, United States.
authors.forename: Ben
authors.initials: B
authors.lastname: Tomlinson
authors.affiliation: Division of Hematology Oncology, and University of California Davis Comprehensive Cancer Center, UC Davis School of Medicine Sacramento, CA, United States; UC Davis Department of Public Health Sciences, UC Davis School of Medicine, Davis, CA, United States.
authors.forename: Lihong
authors.initials: L
authors.lastname: Qi
authors.affiliation: Division of Hematology Oncology, and University of California Davis Comprehensive Cancer Center, UC Davis School of Medicine Sacramento, CA, United States; UC Davis Department of Public Health Sciences, UC Davis School of Medicine, Davis, CA, United States.
authors.forename: Rosemary
authors.initials: R
authors.lastname: Cress
authors.affiliation: Division of Hematology Oncology, and University of California Davis Comprehensive Cancer Center, UC Davis School of Medicine Sacramento, CA, United States.
authors.forename: David R
authors.initials: DR
authors.lastname: Gandara
authors.affiliation: Division of Hematology Oncology, and University of California Davis Comprehensive Cancer Center, UC Davis School of Medicine Sacramento, CA, United States. Electronic address: Karen.kelly@ucdmc.ucdavis.edu.
authors.forename: Karen
authors.initials: K
authors.lastname: Kelly
mesh_terms: D000328:Adult; D000368:Aged; D002140:California / Q000453:epidemiology; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality* / Q000628:therapy; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012042:Registries; D016019:Survival Analysis
keywords: Cause specific survival; Epidemiology; Non-small cell lung cancer; Prognosis; Registry analysis; Young patients