Pack-years of cigarette smoking as a prognostic factor in patients with stage IIIB/IV nonsmall cell lung cancer

Cancer. 2010 Feb 1;116(3):670-5. doi: 10.1002/cncr.24813.


Background: This study was undertaken to characterize the relation between the survival of patients with stage IIIB/IV nonsmall cell lung cancer (NSCLC) and pack-years of cigarette smoking (graded according to the American Joint Committee on Cancer staging system).

Methods: Data were analyzed from patients with stage IIIB/IV NSCLC who had completed a prospective smoking questionnaire. The impact of pack-years of cigarette smoking, age, sex, Karnofsky performance status (KPS), and the presence of weight loss >5% was evaluated on overall survival using univariate and multivariate analyses.

Results: Smoking history and clinical data were available for 2010 patients with stage IIIB/IV NSCLC (1004 women and 1006 men). Approximately 70% of patients (1409 patients) had smoked >15 pack-years, 13% (270) were former and current smokers who had smoked < or = 15 pack-years, and 16% (331) were never-smokers (<100 lifetime cigarettes). Never-smokers had a longer median survival compared with former or current smokers (17.8 months vs 11.3 months; log-rank P < .001). Among smokers, patients with a < or = 15 pack-year history of smoking had a longer median survival than patients who had smoked >15 pack-years (14.6 months vs 10.8 months; log-rank P = .03). As the number of pack-years increased, the median overall survival decreased (log-rank P < .001). Multivariate analysis indicated that a history of smoking was an independent prognostic factor (hazard ratio, 1.36; P < .001).

Conclusions: More cigarette smoking, measured in pack-years, was associated with decreased survival after a diagnosis of stage IIIB/IV NSCLC. Trials assessing survival in patients with stage IIIB/IV NSCLC should report a detailed cigarette smoking history for all patients.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Non-Small-Cell Lung / mortality*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Dose-Response Relationship, Drug
  • Female
  • Humans
  • Lung Neoplasms / mortality*
  • Lung Neoplasms / pathology
  • Male
  • Middle Aged
  • Neoplasm Staging
  • Prognosis
  • Smoking / adverse effects*
  • Survival Analysis
  • Treatment Outcome