Small-cell lung cancer: prognostic factors and changing treatment over 15 years

The incidence of small-cell lung cancer (SCLC) has decreased over several decades. Sixty-eight thousand six hundred eleven patients with SCLC in the National Cancer Data Base (NCDB) were analyzed to describe demographic, treatment, and survival changes between 1992 and 2007.

Four patient cohorts-diagnosed in 1992, 1997, 2002, and 2007-were examined. Univariate and multivariate analyses were performed to determine changes in demographic and treatment factors and their effect on survival of limited SCLC (LSCLC) and extensive SCLC (ESCLC).

The proportion of female patients increased, whereas the proportion of non-Hispanic white patients decreased. Median survival for patients with ESCLC and LSCLC was 6.1 and 12.9 months, respectively, and was not significantly improved between patients diagnosed in 1992 and 2002. Improved survival was associated with female sex, age < 70 years, and receipt of surgery for patients with LSCLC. Radiation therapy decreased the hazard ratio (HR) for patients with stage III LSCLC but not for patients with earlier stage disease. Chemotherapy decreased the HR for all patients with LSCLC. Patients with ESCLC treated with radiation in addition to chemotherapy had better survival than those who received only chemotherapy.

Despite changes in demographics and treatment, the median and 5-year survival rates for patients with SCLC have not significantly improved over the past 15 years. Surgery was associated with improved survival in LSCLC. The benefit of chemotherapy and/or radiation therapy was dependent on American Joint Committee on Cancer (AJCC) stage. AJCC staging information had prognostic and treatment ramifications and should be collected in future studies and databases.