Usefulness of bile cytology with endoscopic suction immediately after of the biliary stent placement for malignant biliary strictures

Abstract

We devised a bile cytology method using endoscopic suction for convenient sample collection of bile spillage occurring immediately after biliary stent placement, and investigated its usefulness. The subjects were 19 patients who underwent biliary stenting after having been diagnosed with malignant biliary strictures at our hospital between March and December 2015. Final cancer diagnosis was based on all sampling methods and clinical follow-up. After completing other tissue collection procedures, we collected bile spillage occurring immediately after biliary stent placement, using endoscopic suction with a tracheal suction kit. The amount of the samples collected by endoscopic suction was 11.9±9.5ml, and samples assessable as cytological diagnosis were obtained in 95% of the cases (18/19 patients). The cancer-positive rate (sensitivity) is 79% (15 out of 19 cases), 95% confidence interval (CI) was 0.54-0.94. No complications occurred due to the collection of bile with suction. Endoscopic suction cytology after biliary stent placement is a useful means of pathological diagnosis for convenient sampling offering high diagnostic sensitivity.