A 48-year-old woman underwent computed tomography (CT) due to epigastric pain. The CT scan revealed a 21 × 17 mm gastric wall mass protruding  into  the  stomach  cavity  (Figure A, arrow). Gastroscopy  confirmed  a  2-cm  submucosal  mass  in the greater curvature (Figure B). and mucosal biopsy was unremarkable. Endoscopic ultrasound found an endophytic- exophytic hypoechoic mass with heterogeneous texture arising from the muscularis propria (Figure C). The nodule was removed using a snare afterendoscopic submucosal dissection (Figure D). The histology confirmed moderately cellular spindle-cell tumor (Figure E) and immunostaining of the tumor cells was positive for S100 (Figure F) and negative for DOG1, CKIT, SMA, and desmin, all consistent with a schwannoma arising from the muscularis mucosa instead of gastrointestinal stromal tumor. As very rare neoplasms of the stomach, schwannomas are mostly asymptomatic and discovered incidentally with exceedingly rare malignant transformation [1, 2]. The overall prognosis of these lesions is unknown. The treatment usually includesendoscopic or surgical resection with the diagnosis mostly made postoperatively by immunohistochemistry [1]. Therefore, we need to consider schwannomas in the differential diagnosis of submucosal gastric tumors of the muscularis propria layer. Surgical excision with negative margins is the recommended treatment of choice because incomplete excision may be relevant with local recurrence or distant metastasis. Endoscopic mucosal resection with intermittent endoscopic surveillance and long-term clinical follow-up evaluation is suggested for small gastric schwannomas because of the rare risk of malignant transformation.We are planning to repeat endoscopic surveillance in 1 year for our patient.

Acknowledgements

Funding: This work was supported by National Natural Science Foundation of China (31600134).

Conflicts of Interest: The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects  of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Written informed consent was obtained from the patient for publication of this “Images in Clinical Medicine”.