Comparison of cisplatin/etoposide versus carboplatin/etoposide concurrent chemoradiation therapy for limited-stage small cell lung cancer (LS-SCLC) in the elderly population (age >65 years) using national SEER-Medicare data.

PURPOSE: Standard therapy for limited-stage small cell lung cancer (SCLC) (American Joint Committee on Cancer stages I-III) is concurrent chemoradiation therapy (CRT) with cisplatin/etoposide (EP), but carboplatin/etoposide (EC) is often used in clinical practice. Though a growing proportion of this disease is diagnosed in older patients, there are limited studies of older patients comparing cisplatin to carboplatin. This study compared survival outcomes of elderly patients with limited-stage SCLC treated with concurrent EC or EP and radiation.

METHODS AND MATERIALS: Limited-stage SCLC diagnosed at ages 66 to 80 years during 1992 to 2007 were selected from the Surveillance Epidemiology and End Results-Medicare database to compare EP with EC. Concurrent CRT was defined as starting radiation and cisplatin or carboplatin within 14 days. Study endpoints were overall survival (OS, time from diagnosis until death) and cause-specific survival (CSS, time from diagnosis until death from lung cancer).

RESULTS: Final analysis included 565 cases: 219 EP (39%) and 346 EC (61%), with median age 72 and gender ratio 1.0. A majority of the cases were stage III (85%). Median and 5-year OS were 13.8 months (95% confidence interval [CI], 11.4-15.0 months) and 10.2% (95% CI, 6.2-15.3%) for EP, versus 13.7 months (95% CI, 12.0-15.6 months) and 10.9% (95% CI, 7.6-14.8%) for EC (P = .51). CSS were also similar (P = .91). OS and CSS were not statistically different in single- or multivariable survival analysis.

CONCLUSIONS: EC and EP had similar survival outcomes, suggesting EC could be used with (or instead of) EP as the standard of care, at least in the elderly population.