Introduction: We conducted a phase II study of combination chemotherapy with irinotecan (CPT) and cisplatin (CDDP) in patients with advanced large-cell neuroendocrine carcinoma (LCNEC) of the lung.
Methods: Patients received irinotecan (60 mg/m², days 1, 8, and 15) and cisplatin (60 mg/m², day 1) every 4 weeks for up to four cycles. The primary endpoint was the response rate. Expected and threshold values for the primary endpoint were 50% and 30%.
Results: Forty-four patients were enrolled between January 2005 and November 2011. The response rate (RR) was 54.5% (95% confidence interval [CI], 38.8-69.6%). The median progression-free survival time was 5.9 months (95% CI, 5.5-6.3), and the median survival time was 15.1 months (95% CI, 11.2-19.0). A central pathological review of specimens from 41 patients demonstrated that 30 patients had LCNEC but that 10 patients had small-cell lung cancer (SCLC) and one had non-small-cell lung cancer with a neuroendocrine structure. The RR was 46.7% (95% CI, 28.3-65.7%) in the LCNEC group and 80% (95% CI, 44.4-97.5%) in the SCLC group (p = 0.0823). The median survival time was 12.6 months (95% CI, 9.3-16.0) in the LCNEC group and 17.3 months (95% CI, 11.2-23.3) in the SCLC group (p = 0.047).
Conclusions: Combination chemotherapy with irinotecan and cisplatin was active in patients with LCNEC, but the RR and the overall survival period among the patients with LCNEC seemed to be inferior to those among the patients with SCLC. Small numbers of patients were a major limitation in this study.