title: The impact of smoking status on the behavior and survival outcome of patients with advanced non-small cell lung cancer: a retrospective analysis.
abstract: OBJECTIVE
  There are fundamental differences in characteristics between smokers and nonsmokers with non-small cell lung cancer (NSCLC). We aim to study the impact of smoking status on the behavior of the disease, and to identify differences in outcome between the two groups.
  
  
  METHODS
  A retrospective analysis was done of patients with NSCLC seen during the period from January 1999 to August 2002. Clinical characteristics, survival outcome, and response to treatment were reviewed and compared between the smokers and nonsmokers.
  
  
  METHODS
  Department of Medical Oncology, National Cancer Center.
  
  
  RESULTS
  Of 317 patients analyzed, 117 patients (36.3%) were nonsmokers. Among the nonsmokers, 74.5% had adenocarcinoma and 73.9% were women. The smokers had poorer performance status, reported more weight loss, and had a higher mean age at diagnosis of almost 8 years than nonsmokers. One hundred eighty-seven patients (59%) had died as of December 31, 2002. The nonsmokers had a longer median survival, although this was not statistically significant. There were no statistically significant differences in survival and response to chemotherapy between the two groups after adjusting for known prognostic factors.
  
  
  CONCLUSIONS
  Despite the known differences in mutational spectra and clinical characteristics between smokers and nonsmokers with NSCLC, no differences in terms of response to chemotherapy and survival outcome were observed. This could imply that this disease is equally aggressive in these two groups. More research is needed to further delineate and characterize the differences between these two etiologically different forms of NSCLC.
authors.affiliation: Department of Medical Oncology, National Cancer Center, 11 Hospital Drive, Singapore 169610.
authors.forename: Chee-Keong
authors.initials: CK
authors.lastname: Toh
authors.forename: Ee-Hwee
authors.initials: EH
authors.lastname: Wong
authors.forename: Wan-Teck
authors.initials: WT
authors.lastname: Lim
authors.forename: Swan-Swan
authors.initials: SS
authors.lastname: Leong
authors.forename: Kam-Weng
authors.initials: KW
authors.lastname: Fong
authors.forename: Joseph
authors.initials: J
authors.lastname: Wee
authors.forename: Eng-Huat
authors.initials: EH
authors.lastname: Tan
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000209:etiology / Q000401:mortality*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000209:etiology / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects*; D015996:Survival Rate; D016896:Treatment Outcome; D015431:Weight Loss