Xanthogranulomatous gastritis of the remnant stomach mimicking a malignant tumor: A case report.

Xanthogranulomas are known to develop in the gallbladder and kidney. Xanthogranuloma of the stomach is a rare disease, and to the best of our knowledge, only a few cases have been reported to date. The present patient was a 64-year-old man who underwent a wide resection of the stomach following a Billroth-I reconstruction for a gastric ulcer ~40 years prior to the current presentation. Due to tarry stools, a gastrointestinal endoscopy was performed, leading to identification of an ulcerated gastric lesion located at the previous suture line at the lesser curvature of the remnant stomach. This lesion was elevated, appearing to indicate a submucosal tumor. Positron emission tomography revealed uptake of fluorodeoxyglucose radiotracer by the tumor. Although not indicated by the biopsy specimens, a malignant tumor of the remnant stomach was suspected, in the form of a malignant gastrointestinal tumor or remnant gastric cancer. Curative resection of the tumor was successfully performed. Histological examination of the resected specimens revealed xanthogranulomatous inflammation consisting of foamy histiocytes and plasma cells, however, no cancer cells were observed. The tumor was diagnosed as xanthogranulomatous gastritis that mimicked a malignant tumor of the remnant stomach. The present study therefore indicates that inflammatory tumors should be considered in the differential diagnosis of malignant tumors.