Real-World Epidemiological Analysis of Gastrointestinal Neuroendocrine Carcinomas: A TriNetX-Based Study

Introduction: Gastrointestinal neuroendocrine carcinomas (GI-NECs) are a diverse group of aggressive tumors with variable clinical outcomes. Although progress has been made in classifying and treating these cancers, detailed real-world data on their anatomical distribution and survival rates are scant. This study utilizes a large database to explore the epidemiological and anatomical distribution patterns and to assess the survival outcomes of GI-NECs. Methods: We accessed the TriNetX global health research network, comprising about 197 million patient records from 160 healthcare organizations, to perform a retrospective analysis of GI-NEC cases through November 2024. Patients were identified via the ICD-O-3 morphology code 8246/3. We analyzed TNM staging and survival rates across various GI locations. Results: We identified 4,515 cases of NECs with a nearly equal gender distribution (47.27% male, 47.35% female) and an average age of 71 years. Unknown primary sites were the most common (n=692) followed by Small intestinal NECs (n=682) and others. The least common were liver and intrahepatic biliary NECs (n=71). Survival varied significantly by site, from a high of 37.5% in small intestinal NECs to just 11.4% in hepatic/biliary NECs, highlighting notable differences even within the same organ, such as between appendiceal and cecal NECs (44.8% vs. 26.4%). Conclusions: This study highlights the necessity for site-specific treatment and improved diagnostic strategies, especially for the worst-prognosis NECs found in hepatic and biliary locations. Our findings are vital for developing targeted therapies and refining prognostic tools based on anatomical sites.