Intraductal papillary mucinous tumor of bile ducts radiologic and pathologic features: a case report

Surgical Treatment of Intraductal Papillary Neoplasm of the Bile Duct: A Report of Two Cases and Review of the Literature

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare bile duct tumor characterized by intraductal papillary or villous neoplasms covered by neoplastic epithelium with fine fibrovascular stalks in the dilated bile ducts (1). Its true etiology remains unknown. Herein, we report two cases of IPNB that underwent surgical resection. The first case was a 66-year-old male who complained of upper abdominal pain for three years. We found obstruction of the common bile duct and dilation of the intrahepatic and extrahepatic bile ducts after MRCP. Laparoscopic hepatic segmentectomy (S2, S3, S4), resection of the common bile duct, cholecystectomy, and hepaticojejunostomy were performed. The second case was a 67-year-old male with asymptomatic dilation of the intrahepatic duct. The patient underwent robot-assisted laparoscopic hepatic segmentectomy (S5, S6, S7, S8), resection of the common bile duct, hepaticojejunostomy and cholecystectomy.

Intraductal oncocytic papillary neoplasms of the pancreas and bile ducts: a description of five new cases and review based on a systematic survey of the literature

BACKGROUND

Intraductal oncocytic papillary neoplasms (IOPN) are rare tumors of the pancreatic and biliary ductal system. It is not absolutely clear if the molecular and clinicopathologic characteristics of IOPN differ significantly from other related lesions, namely intraductal papillary mucinous neoplasms (IPMN). Therefore it is not clear if it is reasonable to consider IOPN as a separate diagnostic and clinical entity.

METHODS

In order to describe the clinicopathologic characteristics of IOPN and to compare them with the IPMN profile, we performed a systematic review of the literature and additionally studied five previously unreported IOPN cases.

RESULTS

IOPN differ from IPMN by lack of K-ras gene mutations in all studied cases. Several differences in the clinical and biological profile between IOPN and IPMN exist, but they are of quantitative rather than of qualitative nature. Additionally, pancreaticobiliary or gastric-foveolar IPMN components may coexist with IOPN component within a single lesion, which suggests at least a partial relation of the pathogenetic pathways of IPMN and IOPN. Importantly, the pathogenesis of accumulation of mitochondria and oxyphilic appearance of IOPN remains unknown.

CONCLUSIONS

At present, there are no reliable criteria other than histopathological picture and K-ras gene status to differentiate IOPN from IPMN. In particular, no clear differences in optimal treatment options and prognosis between these tumors are known. Further studies are needed to clarify the biology of IOPN and to establish their position in clinicopathologic classifications of pancreatic tumors.