Rare Case of Gastric Schwannoma Simulating Gastrointestinal Stromal Tumor—a Case Report

Gastrointestinal neurogenic tumors are derived from autonomic components of Auerbach’s plexus. The most common site for gastrointestinal schwannoma is the stomach. Gastric schwannoma is a rare, benign, slow-growing neoplasm representing 0.2% of all gastric tumors. They are usually asymptomatic or present with nonspecific symptoms. They have excellent prognosis after surgical resection. We report a rare case of gastric schwannoma in a 56-year-old woman who presented with abdominal discomfort and vomiting since few years. Contrast-enhanced computed tomography showed a well-defined homogenous hypodense lesion arising from the anterior wall of the body of stomach with endophytic and exophytic components. Progressively increasing homogenous contrast enhancement of the lesion was noted. There was no hemorrhage, cystic change, necrosis, or degeneration within the lesion. Wedge gastrectomy was done with a possible diagnosis of gastrointestinal stromal tumor, but was confirmed to have gastric schwannoma on histopathology. Histopathology showed spindle cells with peripheral cuff of lymphoid aggregates with S-100 protein positivity on immunohistochemistry. Gastric schwannoma should be included in the differential diagnosis of a gastric intramural or exophytic mass when computed tomography shows a well-defined homogenous hypodense lesion showing progressively increasing homogenous enhancement without hemorrhage, necrosis, or degeneration.