Radical intended surgery for highly selected stage IV neuroendocrine neoplasms G3.

Background: Stage IV gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs) G3 are the NENs with the worst prognosis. According to ENETS guidelines, platinum-based chemotherapy is the standard treatment for this population. Surgery is only considered in highly selected "resectable" NENs with usually lower Ki67. However, the role of surgery with curative intent has been poorly investigated.

Objective: To describe, in a retrospective series of stage IV GEP-NENs G3, overall survival (OS) and recurrence-free survival (RFS) rates after curatively intended surgery.

Methods: Multicenter analysis of stage IV GEP-NENs G3 receiving radical resection (R0/R1) from 2007 to 2017, with minimum post-surgical follow-up time of 3 months.

Results: Fifteen patients from 6 NEN referral centers, with median follow-up of 29 months (8-86), were included. Eight cases had a neuroendocrine carcinoma (NEC) and 7 a neuroendocrine tumor G3 (NET G3). Median OS after radical surgery was 59 months. All patients recurred, with a median RFS of 8 months.

Conclusions: Radical surgery might be considered for highly selected stage IV GEP-NENs G3. Larger series are needed to confirm these results.