Good performance of platinum-based chemotherapy for high-grade gastroenteropancreatic and unknown primary neuroendocrine neoplasms.

To evaluate efficacy and safety of platinum and etoposide combination in the treatment of advanced gastroenteropancreatic (GEP) and unknown primary (CUP) neuroendocrine carcinomas (NEC), we analysed the records of 21 consecutive patients treated with this regimen from 1999 to 2012. Objective responses were obtained in 11 patients (52%) and disease stability (DS) in 5 (24%). Median progression-free survival (PFS) was 7 months (95% CI, 5.33-8.66). Median overall survival (OS) was 16 months (95% CI, 14.97-17.03). Patients with limited liver disease had a significantly (p = 0.002) better PFS than patients with extrahepatic disease at diagnosis with 9 months (95% CI, 7.14-10.85) vs. 4 months (95% CI, 1.60-6.40). Two patients experienced durable complete response (30 and 90 months). The most common grade 3-4 toxicities were neutropenia (61%), anaemia (50%), nausea and vomiting (27%) and fatigue (22%). The platinum plus etoposide regimen has an acceptable toxicity profile and is effective in patients with GEP and CUP-NECs.