Update on Pancreatobiliary disorders

The Pancreatobiliary disorders session focused on a number of topics that are very relevant to the practicing gastroenterologist.

Cystic pancreatic neoplasm (CPNs) are common and often present at an asymptomatic stage. They are frequently premalignant and have variable malignant potential. An accurate diagnosis is the key to their management. They are best assessed by cyst fluid analysis. Evaluation of the pancreatic cyst fluid DNA can supplement the findings of the EUS appearance, cyst fluid cytology, tumor markers, and pancreatic enzymes for diagnosis and prediction of malignancy. However, the utility of cyst DNA analysis warrants further study.

There are a number of predictors of malignancy in intraductal Papillary mucinous neoplasm (IPMNs), including the presence of mural modules, the diameter of the main duct, atypical cytopathology preoperatively, and the presence of main duct IPMNs or mixed IPMNs (vs. branch-type). Cyst size may be important in predicting malignancy in branch duct IPMNs, although these data are controversial. The main duct and mixed IPMNs usually require surgical resection, whereas branch-type IPMNs should undergo surveillance with surgical resection reserved for patients with high risk stigmata. Cyst ablation with ethanol with or without paclitaxel is novel approach for management of certain CPNs and is currently undergoing further study. Finally, sulindac may be a chemopreventative agent for IPMNs. New Development in the Management of Acute Pancreatitis the take-home points were: 1) persistent organ failure is the most important marker of severity of acute pancreatitis, 2) walled-off pancreatic necrosis must be distinguished from a pseudocyst, since these two have very different prognoses and treatment algorithms, 3) prophylactic antibiotics are no longer necessary in patients with necrotizing pancreatitis, 4) the role of ERCP and sphincterotomy in severe gallstone pancreatitis without cholangitis or biliary obstruction is controversial, and finally, 5) urgent open surgical debridement for infected necrosis is no longer mandatory.

Comparing necrosectomy vs. a minimally invasive “step-up” approach (percutaneous or endoscopic drainage of the collection followed by video-assisted retroperitoneal debridement if there was no improvement for infected pancreatic necrosis which was recently published in the New England Journal of Medicine. The step-up approach had lower rates of major complications, mortality, multiorgan failure, incisional hernia, diabetes, exocrine insufficiency, and health care utilization. Moreover, the total cost was lower for the step-up approach.

Functional Biliary Diseases: From Biliary Dyskinesia to Sphincter of Oddi Dysfunction (SOD). CCK-stimulated HIDA scan with gallbladder ejection fraction may not be a good predictor of outcome from cholecystectomy. It is more likely that the outcome depends on the patient’s preoperative symptoms than the results of the study. The role of SO manometry and the likelihood of relief following biliary sphincterotomy in patients with SOD were reviewed. In SOD type I, there is no need for manometry, and the predicted benefit following biliary sphincterotomy is around 90%-95%. In biliary SOD type II, there is evidence from two randomized controlled trials that SO manometry predicts outcome from biliary sphincterotomy and therefore is warranted; resolution of symptoms occurs in approximately 85%.

Type III SOD is a much more complex entity. Because ERCP alone in type III SOD has low yield and high risk, she advocated avoiding ERCP with SO manometry, controversial in type III SOD patients but is fertile area of research. Finally, the risks of ERCP in the setting of suspected SOD were stressed. Prophylactic pancreatic stenting was recommended to reduce the incidence and severity of post-ERCP pancreatitis.

The University of Pennsylvania enlightened their audience in his lecture “EUS/ERCP/MRCP-Which Test for What Disease?” There are a variety of common imaging tests used in pancreaticobiliary disease. They focused on MRI/MRCP, ERCP with or without cholangioscopy, and EUS. He emphasized that of these three technologies, MRI/MRCP has no therapeutic capability but has the highest safety margin. ERCP and cholangioscopy offer significant therapeutic options but are associated with the highest complication rate of the three techniques and also are the most costly.

In addition, radiation exposure to the patients and staff is only experienced with ERCP and cholangioscopy. All three techniques are similar in their ability to detection is greatest with endoscopic ultrasound. Moreover, pancreatic cancer stanging is probably best with EUS, although MRI/MRCP has not been as well studied in this setting. Finally, tissue sampling can only be done at EUS and ERCP and cholangioscopy while the yield of sampling in pancreatic cancer is probably best with EUS.