Purpose: We sought to evaluate the activity and tolerance of the rationally designed sequence of paclitaxel-topotecan-etoposide, a nonplatinum regimen, as induction therapy for limited-stage small-cell lung cancer before combined chemo- and radiotherapy.
Patients and methods: Patients with measurable disease, performance status 0 to 2, no prior therapy, and adequate organ function were eligible. Paclitaxel (110 mg/m2, administered intravenously on day 1), topotecan (1.5 mg/m2, administered orally on days 2 to 4), and etoposide (160 mg/m2, administered orally on days 5 to 7 every 21 days), with filgrastim for two cycles, were followed by chest irradiation to 70 Gy (to postinduction tumor volume) concurrent with carboplatin (area under the curve of 5, administered intravenously on day 1) and etoposide (100 mg/m2 on days 1 to 3 every 21 days) without filgrastim for three cycles (five chemotherapy cycles total). We aimed to determine the response rates to induction and overall therapy, overall and failure-free survival, and toxicity. The primary statistical endpoint was to differentiate between complete response rates of 50 and 70% for the overall treatment program.
Results: Between June 2001 and January 2003, 65 patients were enrolled, but one never started therapy, and one was ineligible. Patient characteristics included male/female, 27/36; white/black/other/unknown, 58/3/1/1; median age 62 (range, 38-78); performance status 0/1/2, 27/33/3. Induction chemotherapy resulted in six (10%) complete responses and 35 (56%) partial responses. Overall response to chemoradiotherapy included 27 (43%; 95% confidence interval [CI] 30-56%) complete responses and 24 (38%) partial responses. Median progression-free survival is 12 months (95% CI, 9-15 months). Median overall survival is 20 months (95% CI, 16-24 months). Frequent (>20%) grade 3/4 toxicities during all therapy included neutropenia, febrile neutropenia, anemia, thrombocytopenia, fatigue, and dysphagia. One patient died of febrile neutropenia, one died of febrile neutropenia and typhlitis, and one patient who declined transfusion for anemia died of cardiac ischemia.
Conclusions: This treatment regimen has significant activity in limited-stage small-cell lung cancer but did not meet our prospectively defined criteria for further investigation in this setting. The addition of etoposide and the use of a sequenced administration schedule did not seem to improve overall activity beyond our prior experience with a topotecan-paclitaxel doublet.