Giant solid pseudopapillary neoplasm of the pancreas in a middle-aged man: A case report

M. Iseki , M. Mizuma , H. Yoshida , T. Okada , K. Nakagawa, H. Hayashi , T. Morikawa , S. Ottomo, N. Sakata , H. Ohtsuka , K. Fukase , T. Aoki , F. Motoi , T. Naitoh , Y. Katayose , S. Egawa , M. Unno . Division of Hepato-Biliary-Pancretic Surgery, Department of Surgery, Tohoku University Graduate School of Medicine, Japan Division of Integrated Surgery and Oncology, Department of Surgery, Tohoku University Graduate School of Medicine, Japan Introduction: A solid pseudopapillary neoplasm (SPN) of the pancreas is a rare neoplasm of low malignant potential. It typically afflicts in young women, but uncommon in men. We report giant solid pseudopapillary neoplasm of the pancreas in a middle-aged man. Case report: A 47-year-old manwas admitted to the previous hospital for continuous epigastric pain and bodyweight loss. A giantmasswas palpated in the upper abdominal area. The abdominal CT scan revealed 21 cmmass with central necrosis and peripheral calcification in the pancreas. This tumor showed enhanced solid component in the marginal area. The patient underwent total pancreatectomy with portal vein resection and reconstruction. In the resected specimen, 26 cm tumor of the pancreas, surrounded by a fibrous pseudocapsule, gave rise to central necrosis and intratumoral hemorrhage. Histological examination revealed that the tumor cells with enlarged nucleus and granular eosinophillic cytoplasm were arranged in sheets and nests, forming pseudopapilla formation. They were immunohistologically positive for CD10 and vimentin. Since nuclear accumulation of beta-catenin protein was shown, this tumor was pathologically diagnosed with SPN. This had malignant potential, indicated by venous invasion. Discussion: This case show atypical clinical feature (age, gender) and typical radiographical feature, including the enhancement of solid component and peripheral calcification. Giant SPN with central necrosis and intratumoral hemorrhage is similar to other giant pancreatic tumors, such as neuroendcrine tumor. Giant SPN is difficult to diagnose by imaging modalities preoperatively, especially in men.