The Effectiveness of ERCP Versus MRCP: Final Results of a Randomized Clinical Trial in Patients with an Intermediate Probability of Bile Duct Obstruction

Abstract

Background: Many noninvasive methods of cholangiography, have made us reconsider the role of ERCP in the management of patients with suspected biliary obstruction. Aim: The aim of this study was to assess the effectiveness of MRCP compared to ERCP in patients with this condition. Methods: Following clinical suspicion, laboratory blood work and ultrasound, patients were categorized as having an intermediate probability of bile duct obstruction using a validated predictive model, and were randomized to MRCP or ERCP in a medical effectiveness trial that included a follow-up period of 12 months. Patients were managed according to standardized clinical paths. The main outcome was the occurrence of negative pre-defined outcomes considered disease- or bilio-pancreatic procedure-related. Secondary outcomes were pertinent durations of hospitalization and quality of life measurements (SF-36). Results: Of 350 patients screened over 54 months, 126 patients were randomized to ERCP and 131 to MRCP. ERCP and MRCP groups were similar in age (52.3±18.4 years vs 55.8±7.7 years), sex (65% vs 60% female), presenting symptoms, and post-cholecystectomy status (34% vs 44%). Biliary obstruction was suspected on clinical grounds (72%) or because of ultrasonographic findings (28%). At randomization, bile duct stones and neoplasms were noted in 21% and 24%, and 6.6% and 5.4%, while no obstruction was noted in 53% and 50% of ERCP and MRCP patients, respectively. Mean durations of follow-up were 8.0±5.1 mos for ERCP and 8.4±4.9 mos for MRCP; additional diagnostic or therapeutic tests were performed in 58% (95% CI: 49-67%), and 59% (95% CI: 50-67%), respectively. No clinically significant overall differences in quality of life were noted between both groups. 38% of ERCP's performed in the ERCP group were therapeutic, while 51% of MRCP patients went on to have an ERCP (therapeutic in 90%). Negative outcomes were noted in 19.1% (95% CI: 12.3-25.8%) of MRCP and 14.3% (95% CI: 8.2-20.4%) of ERCP patients (difference of 4.8%, 95% CI: -4.3 to +13.9%.), resulting in respective durations of hospitalization of 4.6±7.5 versus 5.6±8.5 days (P=NS). In both groups, negative outcomes were disease related (72%) or procedure-related (28%). Conclusion: In this medical effectiveness randomized trial, a policy of early MRCP did not exhibit significant advantages over one of early ERCP in the work-up of patients with an intermediate probability of biliary obstruction.