Gastric Schwannoma: Incidentally Found Rare Gastric Tumor Presented with Nonspecific GI Symptom

Abstract

Gastric schwannomas (GSs) are generally slow-growing, asymptomatic encapsulated tumors of mesenchymal origin arising from Schwann cells of nerve plexus within the gastric wall. Schwannomas are rare in the stomach, and account only 0.2% of all gastric tumors. Among mesenchymal tumors in the gastrointestinal (GI) tract, gastrointestinal stromal tumors (GISTs) are the most common, and 60–70% of them occur in the stomach. Under endoscopic examination, GS/GSs and GIST/GISTs appear grossly similar as firm submucosal neoplasm. The most common presenting symptom is upper gastrointestinal bleeding, followed by abdominal pain. Here, we report a 77-year-old lady presented with progressive weakness, and received prompt esophagogastroduodenoscopy (EGD) due to anemia. The EGD revealed a submucosal tumor with hemorrhagic ulceration at the middle to lower body of the stomach. After contrast-enhanced computed tomography (CT), the patient received partial gastrectomy with initial impression of GIST/GISTs, but confirmed as schwannoma postoperatively. This case highlights the importance of considering schwannomas as a differential diagnosis when preoperative imaging studies revealed a submucosal, exophytic gastric mass. The case also underscores the value of prompt EGD survey even for normocytic anemia with negative stool occult blood and nonspecific GI symptoms, especially when it comes to the elderly.