Multiple Sampling Method Increases the Diagnostic Yield in Non Pancreatic Malignant Biliary Obstruction (MBO)

Abstract

Background and Aim: The yield of brush cytology (Cyt) in malignant bile duct (BD) strictures is low, multiple sampling methods have given variable results. Our database has been prospectively recording our experience with intraductal sampling with biopsy block Cyt (B x C) and brush Cyt (BrC) as part of a QA exercise. We report our experience with our last 43 cases of non pancreatic MBO. Materials and Methods: Once a suspicious bilary stricture is identified @ ERCP and a 0.035” guidwire inserted, a 9.6 French (Fr) biliary cannulation sleeve (Cook Medical, Winston Salem) with its 6 Fr inner guide catheter are advanced over the wire and through the stricture. The guide catheter and wire removed. Through the sleeve a pediatric Bx forceps (Boston Scientific, Boston) and a cytology brush with a 5 or 6 Fr covering catheter are inserted and the sleeve repositioned in the duct to allow sampling. 4 bx specimens from within the stricture and the brush are sent in preservative for Cyt evaluation. For this study pathology reading of malignancy is our only positive recording, while suspicious and atypical diagnoses are considered negative. Results: 110 strictures were evaluated, 16 were benign, 51 were primary pancreatic and 43 non pancreatic (cholangioCa-27, gallbladder-8, metastatic 8)and they are reported here. Each sampling method was compared to both in combination using a Chi Square analysis in the table below. 37/43 cases were positive by @ least one sample. Of the 6 negatives (3 suspicious and 3 negative)were confimed cancers by EUS, PTC or surgery. After sampling is completed the sleeve system could be used to insert a 10 Fr plastic stent, or a metal inserted over the wire. Combined sampling was stastically superior to either method alone. Conclusions: 1). Combining BrC and BxC is statistically superior to either alone. 2). Using the sleeve system for multiple sampling gives a high overall yield. 3). This sampling method would not confer the risk of seeding the biopsy tract like percutaneous or EUS sampling in surgical candidates Tabled 1 Method # positive (%) cumulative (BrC + BxC) (%) P value BrC 27/43 (63%) 37/43 (86%) p = 0.01 BxC 29/43 (67%) 37/43 (86%) P = 0.05 Open table in a new tab