Type 2 gastric carcinoids occur in ZES patients, primarily in patients with multiple endocrine neoplasia type 1(MEN1/ZES), comprise 5–6% of all gastric carcinoids, are well-differentiated, are also gastrin-dependent, and malignant in 10–30% [58,59,60]. Here, GAST is linked to multiple endocrine neoplasia type 1.