An extremely rare case who underwent total remnant pancreatectomy due to recurrent pancreatic metastasis of intraductal tubulopapillary neoplasm

We describe a rare case of recurrent pancreatic metastasis of intraductal tubulopapillary neoplasm (ITPN). A 53-year-old woman diagnosed with an intraductal papillary mucinous neoplasm (IPMN) and a pancreatic ductal adenocarcinoma (PDAC) of the pancreatic body underwent a distal pancreatectomy. The tumor was composed of cuboidal, high-grade dysplastic cells proliferating in a tubulopapillary growth pattern without mucin production; hence, the final diagnosis was ITPN. A follow-up computed tomography scan revealed an enhanced 2 cm mass of the pancreatic head 3 years after the surgery. From workup investigations, the patient was diagnosed with PDAC or a recurrent ITPN of the remnant pancreas. A total remnant pancreatectomy was then performed. Histopathological findings revealed that the new ITPN had the same features as the prior ITPN. In IPMNs, the presence of an invasive component and high-grade dysplasia can lead to progression to a recurring IPMN and the development of PDAC. Because there have been few reports of recurrent ITPN developing into PDAC, the risk factors for ITPN have not been investigated. Because of the uncertain clinicopathological characteristics of ITPN, more data should be gathered to assess the long-term outcome and malignant potential of ITPN.