[A Case of Primary Gastric Adenocarcinoma with Enteroblastic Differentiation(GAED)].

Gastric adenocarcinoma with enteroblastic differentiation(GAED)is a rare disease that is classified as a special type in the 15th edition Japanese Classification of Gastric Carcinoma. GAED is considered to have a poor prognosis. We report about a 76-year-old man with GAED who presented with complaints of poor appetite and weight loss. He was suspected of having gastric cancer based on ultrasonography and computed tomography findings and was referred to our hospital by his home doctor. Upper gastrointestinal endoscopy revealed a gastric cancer in the lesser curvature of the gastric antrum. Distal gastrectomy was performed. Histopathology showed a moderately differentiated adenocarcinoma with a clear cytoplasm. Immunostaining was positive for Sal-like protein 4(SALL4)and negative for α-fetoprotein(AFP). The patient was diagnosed as having GAED. Vascular and lymphatic invasion were not observed. He was discharged on the 9th day after surgery. At 5 months postoperatively, he was treated with adjuvant chemotherapy, and no recurrence was noted. GAED is a rare disease with a poor prognosis. We report this case and discuss relevant literature.