一名45岁的男性前往我们医院进行体检，没有任何临床症状。患者进行了胃镜检查，发现胃体小弯处有一个直径为30mm×30mm的半球形粘膜下肿瘤，初步诊断为胃肠道间质瘤（GIST）。决定采用内镜切除术是最佳选择，患者接受了内镜全层切除和内镜钳形缝合术。除了轻微低热外，患者康复良好，并在术后第7天出院。病理分析和免疫组化染色显示肿瘤性舒万氏细胞呈束状生长，高度阳性表达S-100蛋白，确诊为胃舒万氏瘤。

A 45-year-old male visited our hospital for a medical examination without any clinical complaints. The patient had an gastroscopy, which revealed a 30mm*30mm hemispherical submucosal tumor arising from the lesser curvature of the gastric body , suggesting a gastrointestinal stromal tumor (GIST) as a preoperative diagnosis;Endoscopic resection was determined to be the best choice and the patient underwent a endoscopic full-thickness resection and endoscopic purse-string suture. Except for a slight low fever, the patient was well recovered and was discharged on his 7th post-operation. Pathological analysis and immunohistochemical staining showed fascicular growth of neoplastic Schwann cells and confirmed the diagnosis of gastric schwannoma through high positivity for S-100 protein.