A case of type I gastric NET with AIG treated by ESD

A 79-year-old man presented with abdominal pain. Esophagogastroduodenoscopy (EGD) revealed two lesions in the gastric body. Biopsy confirmed a well-differentiated neuroendocrine tumor (NET G1). EGD showed atrophy in the gastric body, but not in the antrum, indicating reverse atrophy typical of autoimmune gastritis (AIG). Based on these endoscopic findings, he was diagnosed as type I gastric NET (G-NET). Endoscopic submucosal dissection (ESD) was performed for both lesions. One lesion was intramucosal, with venous invasion. According to the current guidelines, type I G-NETs without muscularis propria (MP) invasion or lymph node metastasis can be managed without additional treatment. However, recent studies have suggested that venous invasion may be associated with an increased risk of lymph node metastasis. Therefore, careful long-term surveillance was required for him.