Apparent Endoscopic Decrease in the Size of a Large Ulcerated Gastric Schwannoma After Helicobacter pylori Eradication Therapy: A Case Report

ABSTRACT Gastric subepithelial lesions (SELs) comprise a heterogeneous group of tumors, among which gastric schwannomas are rare and generally benign. We report a case of a large gastric schwannoma with ulceration and symptomatic anemia that showed an apparent endoscopic decrease in size following Helicobacter pylori eradication. An 85‐year‐old man presented with iron deficiency anemia. Esophagogastroduodenoscopy revealed a large ulcerated SEL in the lower body of the stomach, along with multiple gastric ulcers. Endoscopic ultrasonography demonstrated a 56 mm tumor originating from the fourth layer, raising suspicion for a gastrointestinal stromal tumor. Boring biopsy from the ulcer base enabled a definitive diagnosis of gastric schwannoma based on immunohistochemical findings. Although surgical resection was recommended, the patient declined. After successful H. pylori eradication, follow‐up endoscopy at 6 months showed healing of the ulcerative lesion and an apparent endoscopic decrease in the size of the tumor. Although objective post‐treatment assessment was unavailable, this case suggests that inflammatory or ulcer‐related changes associated with H. pylori infection may influence the endoscopic appearance of gastric SELs.