A rare case of gastric schwannoma mimicking GIST: diagnostic and therapeutic approach.

Gastric schwannomas are rare, benign neurogenic tumors originating from Schwann cells within the gastrointestinal tract, comprising only 0.2% of all gastric tumors. This report presents the case of a 32-year-old female patient who experienced severe periumbilical pain, nausea, and vomiting, ultimately diagnosed with gastric schwannoma. Initial imaging and endoscopic evaluations suggested a gastrointestinal stromal tumor (GIST), but postoperative histopathological analysis confirmed schwannoma, showing S-100 positivity and negativity for CD117, DOG-1, SMA, Desmin, and CD34. The patient underwent successful central gastrectomy with negative surgical margins and no metastasis. Despite a postoperative complication of small bowel obstruction, which was managed conservatively, the patient remained symptom-free with no recurrence over the follow-up period. This case underscores the importance of differential diagnosis, distinguishing schwannomas from GISTs and other submucosal lesions through thorough histopathological and immunohistochemical analyses, and highlights the efficacy of complete surgical resection in preventing recurrence.