Primary Duodenal Carcinoma with Embryonal Carcinoma Features in a Young Man.

We present the case of a 35-year-old man with intractable nausea, vomiting, and severe anemia. A computed tomography (CT) scan of the chest, abdomen, and pelvis showed a circumferential lesion thickening of up to 3.5 cm at the level of the third portion of the duodenum. No aortocaval, retroperitoneal lymphadenopathy, nor secondary lesion was observed. Esophagogastroduodenoscopy (EGD) revealed a circumferential mass within the third portion of the duodenum. Histopathology of biopsy materials from the duodenal mass showed it most likely to be a poorly differentiated adenocarcinoma. The patient underwent a subtotal stomach-preserving pancreaticoduodenectomy with regional lymph node dissection. Histologically, tumor cells with basophilic cytoplasm and pleomorphic nuclei showed a solid pattern, and expressed CD30 and SALL4 immunohistochemically, leading to a diagnosis of embryonal carcinoma-like tumor. No other primary tumor could be identified, and the location of the tumor, mainly on the mucosal surface, suggested a duodenal origin. The UICC TNM staging was T3N2M0, stage IIB. This is a rare case of primary duodenal carcinoma with features of embryonal carcinoma.