A case of intraductal tubulopapillary neoplasm of pancreas with severe calcification, a potential pitfall in diagnostic imaging.

We experienced a case of intraductal tubulopapillary neoplasms (ITPN) of the pancreas with severe calcification, which complicated image diagnosis. A pancreas head tumor was detected in a Japanese female in her 50s. Early enhancement by contrast-enhanced CT and coarse calcification suggested a neuroendocrine tumor, although the obstruction and dilation of the main pancreatic duct appeared to be an intraductal tumor. An endoscopic ultrasound-guided fine needle aspiration biopsy specimen revealed adenocarcinoma tissue. Pancreaticoduodenectomy was performed, and the patient has been well without evidence of recurrence for over 10 months. Pathological examination on the resected specimen revealed that the tumor showed papillary and tubulo-cribriform growth patterns. Together with typical immunohistochemical results, the final diagnosis of ITPN was made. Characteristically, this case showed extensive calcification of both psammoma body-type and non psammoma body-type with foamy macrophage aggregation. This is the first report of ITPN with two types of calcification and macrophage. Since calcification might be one of the characteristic histological findings in ITPN as shown in our case, the possibility of ITPN should be also considered when calcification is detected in pancreatic lesions by various imaging modalities.