High-Grade Gastrointestinal Neuroendocrine Carcinomas: Multidisciplinary Approach Can Improve Survival Outcomes

There is limited evidence for the presentation patterns and outcomes of patients with high-grade gastrointestinal neuroendocrine carcinomas (HG-NEC).

Patients diagnosed with HG-NEC, defined as having a pathological diagnosis of neuroendocrine cancer with an epicenter of cancer in the gastrointestinal tract and Molecular Immunology Borstel-1 index ≥ 20% between May 2014 and May 2022 were retrospectively analyzed for demographic variables, survivals, and prognostic parameters. The primary endpoint of the study was the estimation of median overall survival (OS) by the Kaplan-Meier method.

A total of 336 patients were included in the analysis, of whom 283 patients (84%) were started on cancer-directed treatment while 53 patients (16%) were planned for best supportive care. The most common sites of the primary were gallbladder (45%), colorectal (19%), and pancreas (13%), with 253 patients (75%) having metastatic NEC. All treated patients received systemic therapy (commonly platinum and etoposide), while 64 patients (23%) underwent resection of the primary. With a median follow-up of 65.4 (45.6 -85.3) months, the median OS of the entire cohort was 15.8 months. The prospective multidisciplinary tumor (MDT) board decision of classifying patients into resectable, unresectable, and metastatic HG-NEC was prognostic for OS (26.8 vs. 21.1 vs. 13.5 months; p  = 0.001). Patients who were able to undergo multimodality therapy (resection and systemic therapy) had improved OS compared with patients on systemic therapy alone (23.1 vs. 14.9 months; p  = 0.003).

A majority of patients with HG-NEC present with advanced disease. An MDT is essential to deciding initial therapeutic strategies in these patients, with patients undergoing resection and systemic therapy having improved OS.