Micro neuroendocrine tumors diagnosed by screening endoscopy

Abstract

Neuroendocrine tumors (NETs) of the gastroenteric system are rare neoplasms with an estimated incidence of 3.51 per 100,000, and the incidence of NETs has increased. Small NETs are usually asymptomatic and sometimes detected by screening endoscopy.

We reported three cases of gastroduodenal NETs diagnosed by screening endoscopy. As for gastric NETs, they had type A gastritis. Gastric tumors were recognized as yellowish SMT-like lesions and duodenal tumor was recognized as yellowish depressed lesion. Pathology showed their nested, trabecular arrangement, and they were found to be positive for synaptophysin through immunohistochemistry. As all tumors were G1 and limited to the submucosa, endoscopic resection was performed.

Since endoscopic resection is considered for small size NETs (diameter of ≤ 10 mm), appropriate biopsy should be performed for small yellowish tumors.