Undiagnosed Borrmann type IV gastric cancer despite repeated endoscopic biopsies and PET-CT examination: A case report.

Borrmann type IV gastric cancer is a particular histological type of carcinoma, which has the characteristic of diffused infiltration that invades the entire stomach, resulting in the thickening and stiffness of the stomach wall. Borrmann type IV gastric cancer is known for the difficulty of detecting tumor cells in endoscopic biopsy specimens. This is crucial in obtaining the pathological results to make a therapeutic decision. The case reported in the present study was highly suspected to be Borrmann type IV gastric cancer according to the clinical manifestations and gastrointestinal barium meal examinations, but demonstrated negative results in multiple endoscopic biopsies and positron emission tomography-computed tomography (PET-CT) examination. The patient was discharged as no affirmative diagnosis was specified. Two weeks after discharge, the patient was administered to another hospital under emergency treatment due to frequent urination. Cystoscopy examination revealed marked thickening of the right bladder wall over a large area. Biopsy specimens were sampled. Pathological consultation suggested a gastrointestinal original of the lesion, which was most likely poorly differentiated gastric adenocarcinoma with neuroendocrine metastasis to the bladder.