Japanese clinical practice guidelines for congenital biliary dilatation

Abstract

Until now, there have been no practical clinical guidelines for congenital biliary dilatation (CBD). In this review article, the Japanese Study Group on Congenital Biliary Dilatation (JSCBD) propose to establish clinical practice guidelines for CBD. Because the evidence-based literature is relatively small, we decided to create guidelines based on the consensus of experts, using the medical literature for reference. A total of 20 clinical questions (CQs) were considered by the members of the editorial committee responsible for the guidelines. The CQs included the distinct aspects of CBD: (1) Concepts and Pathology (three CQs); (2) Diagnosis (six CQs); (3) Pancreaticobiliary Complications (three CQs); Treatments and Prognosis (eight CQs). Each statements and comments for CQs were made by the guidelines committee members. CQs were finally approved after review by members of the editorial committee and the guidelines evaluation board of CBD. These guidelines were created to provide assistance in the clinical practice of CBD management; their contents focus on clinical utility, and they include general information on CBD to make this disease more widely recognized.

Biliary carcinogenesis in pancreaticobiliary maljunction

“…This leads to oncogene and/or tumor suppressor gene mutation in the epithelia, and subsequently biliary tract carcinogenesis. Therefore, the carcinogenesis of biliary tract cancer accompanying PBM appears to involve the hyperplasia-dysplasia-carcinoma sequence caused by the chronic inflammation induced by pancreatic juice refluxed into the biliary tract, which differs from the adenoma-carcinoma sequence or the de novo carcinogenesis associated with biliary tract cancers in the population without PBM [1,4] (Fig. 2).…”

“…As remnant bile duct mucosa preceding progression to cancer might advance over time, extended or total excision of the biliary tract is necessary. The hepatic side should be transected at the confluence of the right and left hepatic ducts, and the pancreatic side should be transected just above the junction of the bile and pancreatic ducts [1,4,26].…”

“…As most biliary tract cancers that develop in patients with PBM without biliary dilatation are gallbladder cancers, only prophylactic cholecystectomy is performed in many institutions. However, in some institutions, because of a perceived risk of bile duct cancer, the extrahepatic bile duct is excised together with the gallbladder [1,4,26,35].…”

“…For the assessment of biliary dilatation, the maximum diameter of the bile duct is measured by non-pressure imaging modalities such as US or MRCP. As the standard diameter of the bile duct is correlated with age, the diagnosis of dilatation should be based on the upper limit of the bile duct diameter in each patient [3,4].…”

Long‐term outcomes after biliary diversion operation for pancreaticobiliary maljunction in adult patients

“…In most patients, PBM is associated with congenital biliary dilatation (CBD). It is well known that PBM with or without CBD is a risk factor for biliary tract cancer . The reflux of pancreatic juice into the biliary tract caused by PBM is thought to play a significant role in the development of biliary tract cancers, such as gallbladder cancer and cholangiocarcinoma in dilated bile ducts .…”