Gastric Neuroendocrine Tumor by AJCC v9 Stage

**Semantic type:** Neoplastic Process

**Definition:** A term that refers to the staging of gastric neuroendocrine tumors, based on the American Joint Committee on Cancer (AJCC) v9 staging guidelines. This staging system applies only to well-differentiated neuroendocrine tumors of the stomach (NET G1, G2, and G3). It does not apply to carcinoma of the stomach including neuroendocrine carcinoma (NEC), mixed adenocarcinoma-NEC and mixed adenocarcinoma-NET. (from AJCC 9th Ed.)