Gastric Neuroendocrine Tumor G1

**Semantic type:** Neoplastic Process

**Definition:** A well-differentiated, low-grade neuroendocrine neoplasm that arises from the stomach. Most cases arise from the corpus-fundus region. The mitotic count is less than 2 per 2 mm2 and the Ki-67 index is less than 3%. It may be associated with autoimmune chronic atrophic gastritis, multiple endocrine neoplasia type 1, or it may be sporadic.

**Synonyms:** - Gastric ECL Cell NET - Gastric ECL Cell NET G1 - Gastric ECL Cell, Histamine-Producing NET - Gastric Enterochromaffin-Like Cell Neuroendocrine Tumor - Gastric NET G1