Ampullary Carcinosarcoma with Enteroblastic Differentiation: A Case Report.

Adenocarcinoma with enteroblastic differentiation is an extremely rare tumor with poor prognosis and unique pathologic features. The tumor appears to be relatively more common in stomach, with rare cases reported in esophagus, colon, rectum and ampulla. Underrecognition by pathologists may be a contributing factor towards underreporting of this tumor. Combination of carcinosarcoma and enteroblastic differentiation has not been reported so far.We report a unique case of ampullary carcinosarcoma with enteroblastic differentiation in a 59-year-old female, diagnosed in the pancreatoduodenectomy specimen. The carcinomatous component showed features of enteroblastic differentiation characterized by tubular architecture with clear cytoplasm, solid component with trabecular architecture and immunohistochemical expression of SALL4 and AFP. The patient was treated with adjuvant Folfirinox chemotherapy and is disease free at 17 months follow up.