2025 Volume 67 Issue 6 Pages 1175-1179
A 74-year-old man was referred to our hospital for detailed examination of a depressed lesion in the stomach. EGD revealed a 12-mm depressed lesion in the lesser curvature of the antrum. Magnifying endoscopy with narrow-band imaging showed a lesion with an unclear microsurface pattern. Furthermore, the vessels were irregular, different in diameter, and disrupted. The lesion was diagnosed as a possible neuroendocrine carcinoma (NEC) based on biopsy findings. We provided informed consent and performed ESD. Histopathological evaluation of the ESD-resected specimen revealed tumor cells in the mucosa but no adenocarcinoma components. Immunohistochemistry revealed tumor cells immunopositive for synaptophysin, chromogranin, and CD56, with a Ki-67 labelling index of 94.8%; the lesion was diagnosed as NEC.
Few studies have reported endoscopic treatment of early gastric NEC, particularly intramucosal lesions or those without adenocarcinoma components. Here, we report an extremely rare case of early gastric NEC.
