Ampulla of Vater Neuroendocrine Tumor G2

**Semantic type:** Neoplastic Process

**Definition:** A well-differentiated, intermediate-grade neuroendocrine neoplasm that arises from the ampulla of Vater and the periampullary region. The mitotic count is 2-20 per 2 mm2 and/or the Ki-67 index is 3 to 20%.

**Synonyms:** - Neuroendocrine Tumor G2 of the Ampullary Region