High-Grade Gastrointestinal Neuroendocrine Carcinoma Management and Outcomes: A National Cancer Database Study.

Management of patients with high-grade gastrointestinal neuroendocrine carcinomas (HG GI NEC) is based on experience with small-cell lung cancer. In this retrospective review, most patients had advanced disease and pancreatic primary had worse outcomes. Treatment at an academic center, younger age, and use of chemotherapy are associated with improved survival. Patients with early-stage disease treated with resection alone had inferior outcomes compared with patients who received neoadjuvant or adjuvant therapy, suggesting that micrometastases contribute to poor surgical outcomes. The relatively high proportion of positive surgical margin favors downstaging with neoadjuvant therapy to improve resection and lower the risk of systemic recurrence.