Feasibility and Efficacy of Combined Cisplatin and Irinotecan Chemotherapy for Poorly Differentiated Neuroendocrine Carcinomas

No standard treatment has been established for poorly differentiated neuroendocrine carcinoma; the usual recommended treatment is based on the strategy for small cell lung carcinoma. The aim of this study was to evaluate the response of poorly differentiated neuroendocrine carcinoma to the combination of irinotecan and cisplatin in one institution. We retrospectively reviewed 50 poorly differentiated neuroendocrine carcinoma patients treated from September 2005 to April 2011 in our institution. Patients were divided into two stages: limited disease or extensive disease. Forty-four patients received the combination chemotherapy of irinotecan and cisplatin, consisting of 4-week cycles of 60 mg/m(2) irinotecan on days 1, 8, 15 and 60 mg/m(2) cisplatin on day 1. Median age was 60 years. Median follow-up time was 11.4 months. Overall survival did not reach the median, and 1-year overall survival was 67. The response rate was 50 (64 at first line), and progression-free survival was 4.8 months (7.3 months at first line). Grade 34 hematologic adverse events were seen in 29 patients (66) and Grade 34 non-hematologic adverse events were seen in 20 patients (45), but no patients died of adverse events. Multivariate analysis showed a statistically significant relationship with neuron-specific enolase elevation and poor overall survival (P 0.016, hazard ratio 6.261, 95 confidence interval). The combination chemotherapy of irinotecan and cisplatin is moderately effective and feasible, and it should be considered as a treatment option for poorly differentiated neuroendocrine carcinoma.