Oxaliplatin-Fluoropyrimidine Chemotherapy Plus Bevacizumab in Advanced Neuroendocrine Tumors: An Analysis of 2 Phase II Trials

This study aimed to determine the safety and effectiveness of bevacizumab (B) plus FOLFOX or CAPOX in advanced neuroendocrine tumors (NETs) by performing a combined analysis of 2 separate prospective phase II studies. In the FOLFOX/B study, patients received chemotherapy without scheduled breaks in 3 cohorts: carcinoid, pancreatic NET, and poorly differentiated neuroendocrine carcinomas. In the CAPOX/B study, NET subtypes were pooled, and patients were treated with 4 cycles of CAPOX/B followed by optional maintenance therapy. Primary end points were radiographic response rate (RR) after 12 cycles (FOLFOX/B), progression-free survival (PFS) (CAPOX/B), and toxicity (both). Seventy-six patients (FOLFOX/B, n = 36; CAPOX/B, n = 40) were included. In FOLFOX/B, RR for carcinoid at 12 cycles 3/22 (13.6%), median PFS 19.3 months; RR for pancreatic NET at 12 cycles 4/12 (41.7%), median PFS 21 months; RR 1/2 (50%) in poorly differentiated neuroendocrine carcinoma; pooled RR 25% and median PFS 21 months (1-year PFS 68%). In CAPOX/B (pooled NET), RR 18% and median PFS 16.7 months (1-year PFS 65%). Predictable toxicity was observed. Neither study met its primary end point, but radiographic responses and prolonged disease stability in previously progressing patients suggest that selected patients with NET may benefit from oxaliplatin-fluoropyrimidine chemotherapy plus bevacizumab and that the combination may warrant further study.