Cholangiocarcinoma presenting as dysphagia and misdiagnosed as gastritis: a case report

BACKGROUND: Heterotopic tumor is a rare disease. Thus far, no cases of heterotopic cholangiocarcinoma have been reported in the world. Cholangiocarcinoma mainly metastasizes by direct invasion, and it can lead to liver metastasis in its advanced stage. There were few clinical cases of gastric metastasis in advanced tumors, mainly seen in breast cancer, lung cancer, liver cancer, malignant melanoma, choriocarcinoma, and hematological tumors. Metastases of cholangiocarcinoma to the stomach also are exceptionally rare. CASE PRESENTATION: A 58-year-old man was admitted to the hospital because of difficulty swallowing for one year. Upon gastroscopy, we found the tumor at the region of the cardia and gastric fundus. Macroscopical appearance of the tumor suggested its malignant nature. Computed tomography (CT) findings showed that the wall of the cardia, fundus, and stomach body were thickened, suggesting a tumor. Because the patient had obvious difficulty swallowing, we invited cardiothoracic surgeons for consultation. They considered that the patient had definite mechanical obstruction in the lower esophagus; hence, they performed an operation. Immunohistochemical staining revealed low-to-medium differentiated adenocarcinoma (containing mucinous adenocarcinoma components) of biliary origin. CONCLUSIONS: We highlight the importance of the endoscopic biopsy of gastric tumor. However, when its results are inconsistent with the clinician’s judgment, further examination is required. Endoscopic ultrasonography and enhanced CT may be a good choice. If necessary, on the premise of patient acceptance, the diagnosis could be confirmed after surgical excision. Here we report a case of a patient with heterotopic cholangiocarcinoma in the gastric fundus. The most common tissue ectopias in the digestive tract include esophagogastric gastric mucosal ectopia, duodenal gastric mucosal ectopia, and gastric mucosal small intestinal ectopia. Thus far, there have been no reports of ectopic cholangiocarcinoma and associated cancer in the stomach. In addition, metastases of cholangiocarcinoma to the stomach are also exceptionally rare, and most of them are due to a direct invasion. The discovery of the primary lesion is an important clue for the reliable diagnosis in such cases.