The Aberrant Aberration

Abstract

Question: A 59-year-old man was referred for evaluation of a mass found during laparoscopic cholecystectomy performed 11 days prior. The patient initially sought medical evaluation for a palpable mass in his right upper quadrant in addition to a 25-lb weight loss. Ultrasonography revealed a dilated gallbladder with wall thickening and a 2.0 × 1.8 × 1.4-cm mass on the superolateral aspect. At the time of laparoscopic cholecystectomy, a mass adherent to the radial hepatic margin was identified and seemed to invade the perimuscular connective tissue. Pathology was interpreted as invasive, moderately differentiated adenocarcinoma. The patient was referred to our institution. Preoperative testing revealed a CA19–9 level of 277 U/mL (normal, <55 U/mL). He subsequently underwent locoregional lymphadenectomy and partial right hepatectomy (segments IVb and V) for complete oncologic resection. On postoperative day 5, increasing bilious output from his Jackson-Pratt (JP) drain was noted, raising suspicion for bile leak. Endoscopic retrograde cholangiopancreatography (ERCP) demonstrated a bile leak from the cystic duct remnant (Figure A) and other notable findings (Figure B). The cystic duct remnant leak was initially treated with endoscopic sphincterotomy and placement of two 10-F, 9-cm plastic stents into the extrahepatic bile duct. Over the subsequent days, increasing output from the JP drain was noted. The high-volume drainage was noted to have an amylase concentration >17,000 U/L. The previously bilious effluent now appeared colorless and repeat ERCP was performed. What is the diagnosis? See the Gastroenterology web site (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and Images in GI. In addition to the bile leak, there was radiographic evidence of pancreaticobiliary maljunction (PBM) with the pancreatic duct arising from a low-inserting cystic duct remnant (Figure C). Standard endoscopic management of the cystic duct leak using endoscopic sphincterotomy and biliary diversion through stenting (Figure B) was unsuccessful. At repeat ERCP, the anomalous pancreatic duct could not be accessed for diversion of flow through the duodenum; thus, a 7-F, 5-cm pancreatic stent with additional side-holes was placed into the cystic duct remnant. Two 10-F, 9-cm plastic stents were replaced in the extrahepatic bile duct for diversion and to prevent migration of the cystic duct stent. The drain output decreased to <20 mL and the patient was discharged. Repeat ERCP 1 month later revealed complete resolution of the leak. PBM has a prevalence of 0.03% and occurs frequently in patients with choledochal cysts.1Yamao K. Mizutani S. Nakazawa S. et al.Prospective study of the detection of anomalous connections of pancreatobiliary ducts during routine medical examinations.Hepatogastroenterology. 1996; 43: 1238-1245PubMed Google Scholar PBM is defined as a union of the pancreatic and biliary ducts outside the duodenal wall leading to a long common channel (often ≥15 mm). The junction is beyond the influence of the sphincter of Oddi, resulting in reciprocal reflux of biliary and pancreatic juices. Persistent reflux of proteolytic pancreatic enzymes and phospholipase A2 is postulated to injure the biliary epithelium and induce metaplasia or promote carcinogenesis.2Shimada K. Yanagisawa J. Nakayama F. Increased lysophosphatidylcholine and pancreatic enzyme content in bile of patients with anomalous pancreaticobiliary ductal junction.Hepatology. 1991; 13: 438-444Crossref PubMed Scopus (122) Google Scholar In addition to evidence of PBM the pancreas duct was directly arising from a low inserting cystic duct. This variant of PBM has not been previously described, but certainly resulted in direct reflux of pancreatic juices into the cystic duct and gallbladder, likely contributing to gallbladder cancer. The association of PBM and gallbladder cancer was established in the 1980s, and most reports cite an incidence of 10%–15% of gallbladder cancer arising in this setting.