Gastric neuroendocrine tumor arising from heterotopic pancreas

There are few English reports on secondary tumors from heterotopic pancreas. Here, we describe a case of gastric neuroendocrine tumor (NET) arising from heterotopic pancreas. A 72-year-old woman underwent esophagogastroduodenoscopy as part of a general health check-up. An endoscopic examination revealed a submucosal tumor on the greater curvature of the gastric body. Laparoscopic and endoscopic cooperative surgery was performed. Histological diagnosis concluded that it was a Grade 1 NET arising from heterotopic pancreas. We report this extremely rare case of a NET presenting as a submucosal tumor, considered to have originated from heterotopic pancreatic tissue.