197 Background: Pancreaticobiliary cancers are difficult to diagnose early and have a high associated mortality. Current methods of obtaining pathologic specimens from a biliary stricture include fine-needle aspiration, brush cytology, and endobiliary forceps biopsy. Among these forceps biopsy is the best, but is frequently limited by its low sensitivity (56%). The goal of this study is to evaluate the diagnostic yield and safety of jumbo forceps biopsies taken from the bile duct. Methods: All patients who presented to a single, tertiary academic referral center from July 2009 to July 2010 with a non-anastomotic biliary stricture were studied. This resulted in 9 patients with common bile duct strictures – 3 male and 6 female (ages 29-83, mean 61). All subjects underwent ERCP by the same gastroenterologist with endobiliary jumbo forceps biopsy using the Boston Scientific Radial Jaw 4 jumbo biopsy forceps. Specimens obtained were compared to available specimens obtained via fine needle aspiration, cytologic brushing or surgical resection. Patients with benign results were followed clinically for 1 year. Results: Three patients had benign biliary strictures as determined by clinical follow-up or surgical resection specimen. Jumbo forceps biopsy diagnosed a benign entity in 100% of these cases. Among the remaining 6 patients with malignant strictures, jumbo biopsy diagnosed a malignancy in 83% of cases. Tissue obtained was deemed adequate for histologic evaluation in 8 of 9 patients. The exception was recognized at the time of the procedure and was attributed to the technical inability to adequately open the biopsy forceps within the bile duct. Of the technically successful cases, 100% yielded an accurate histologic diagnosis as determined by concordant alternative sampling or clinical follow-up. In the 90 days following jumbo forceps biopsy, there were no adverse events such as bleeding, cholangitis, pancreatitis, perforation, peritonitis, or need for hospitalization. Conclusions: In our limited study, the use of jumbo forceps biopsies is safe and, when technically feasible, has a very high yield in evaluating biliary strictures. Larger studies are needed to confirm our findings.