Ampulla of Vater Neuroendocrine Tumor by AJCC v9 Stage

**Semantic type:** Neoplastic Process

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