Including the Sheath Rinse to Improve Cellular Yield in Biliary Brushing Cytology

The incidence of intrahepatic cholangiocarcinoma has been increasing in the last few decades. Interestingly over this period, the incidence of extrahepatic cholangiocarcinoma remained stable. However, the proportion of patients with early stage, small or localized tumors remained the same. This reflects a true increase in the incidence without a corresponding significant gain in our ability to detect cholangiocarcinoma at an earlier stage. As a result, the cholangiocarcinoma related mortality has also increased significantly. Primary sclerosing cholangitis (PSC) is a major risk factor for cholangiocarcinoma in the Western population. Although identification of cholangiocarcinoma at an earlier stage has significantly better outcomes, our ability to detect these early cancers is limited. Tumor markers (CA 19-9 and CEA) may have value for screening in some settings, but effectiveness for detecting small early stage tumors is questionable and magnetic resonance cholangiopancreatography is used in some centers without robust evidence to support its utility. Currently endoscopic retrograde cholangiopancreatography (ERCP) with brush cytology or biopsy is not recommended as screening modality in PSC due to its low sensitivity. However, ERCP with brush cytology is recommended for sampling biliary and pancreatic strictures, but sensitivity continues to be low. False negative results are usually attributed to limitation in cell acquisition and corresponding low cellularity. Techniques have been attempted to improve cell acquisition, including use of intraductal biopsies, alone or in combination with brush cytology and use of large bristle versus small bristle brushes have been examined. Diagnostic accuracy of biliary brushing at our center has been higher than what is reported in the literature. We theorize that it might be due to the fact that we submit both the brush (cut from the neck) and sheath rinse which, to our knowledge, is not a common practice. The underlying hypothesis for this technique is that during the brushing, cells may be dislodged from the brush into the protective sheath. The sheath scrapes the duct wall in the area of stricture potentially further dislodging cellular material into the sheath. The aim of this study was to determine impact of incorporating sheath rinsing on cellular yield of biliary brush cytology. This prospective study was performed at am US tertiary care center. The study protocol was approved by the institutional review board. Consecutive patients who underwent ERCP over a one month period for biliary strictures were enrolled. The procedure was performed by an advanced endoscopist with more than 20 years of experience performing ERCP. The specimens were obtained during the ERCP by brushing the common bile duct, common hepatic duct, and right and left hepatic ducts. A ConMed sheathed colonoscopy brush was used. The brush diameter is 3.0 mm and the sheath outer diameter is 2.1 mm. The brush and the sheath were advanced above the stricture using a monorail technique. The lead edge of the sheath and the brush were advanced and withdrawn through the stricture for a total Received: May 25, 2017 Revised: August 25, 2017 Accepted: August 26, 2017 Correspondence: Frederick C. Johlin Division of Gastroenterology and Hepatology, University of Iowa Hospitals and Clinics, 200 Hawkins drive, 4553D JCP, Iowa City, IA 52242, USA Tel: +1-319-356-4030, Fax: +1-319-535-6399, E-mail: [email protected]