[A Case of Esophagogastric Junction Tumor Diagnosed as an Adenocarcinoma with Enteroblastic Differentiation]

An 81-year-old man who presented at another hospital with a chief complaint of throat congestion underwent upper gastrointestinal endoscopy, which revealed an esophagogastric(EG)junction tumor. The tumor was a Type 3 lesion extending from the lower esophagus to the gastric cardia(cT3N2M0); the patient underwent surgery(left thoraco-laparotomic proximal gastrectomy+lower esophagectomy). The histological examination confirmed the tumor to be a type of adenocarcinoma. Immunostaining of tumor cells showed positive staining for SALL4 and AFP, indicating a diagnosis of adenocarcinoma with enteroblastic differentiation, comprising cells resembling the fetal gastrointestinal epithelium and testing positive for AFP, Glypican-3, or SALL4. Herein, we report a case of a patient with adenocarcinoma with enteroblastic differentiation at the EG junction and present current insights from a literature review.