Multicenter randomized trial comparing diagnostic sensitivity and cellular abundance with aggressive versus standard biliary brushing for bile duct stenosis without mass syndrome

Abstract

Background and aims Diagnosis of cholangiocarcinoma in case of biliary stricture without mass syndrome is obtained by biliary brushing with approximately 50% sensitivity. We performed a multicenter randomized crossover trial comparing the aggressive Infinity brush with the standard RX Cytology Brush. The aims were sensitivity for cholangiocarcinoma diagnosis and cellularity abundance. Methods 51 patients were included. Biliary brushing was performed consecutively with each brush, in a randomized order. Cytological material was studied in a blinded manner concerning the brush. The primary endpoint was sensitivity for cholangiocarcinoma diagnosis, and the secondary endpoint was the abundance of the cellularity obtained with each brush. Cellularity was quantified, in order to determine if one brush strongly outperformed the other. Results Final diagnosis was cholangiocarcinoma (n = 43, 84%), benign (n = 7, 14%) and indeterminate (1 case). Sensitivity for cholangiocarcinoma was 34/43 (79%) for the Infinity brush versus 29/43 (67%) for the RX Cytology Brush (p = 0.096). Cellularity was rich in 31/51 (61%) cases with the Infinity brush and in 10/51 (20%) cases with the RX Cytology Brush (p < 0.001). In terms of cellularity quantification, the Infinity brush strongly outperformed the RX Cytology Brush in 28/51 cases (51%), while the RX Cytology Brush strongly outperformed the Infinity brush in 4/51 cases (8%) (p < 0.001). <b>Conclusions</b> This randomized crossover trial shows that the Infinity brush is not significantly more effective than the RX Cytology Brush for biliary stenosis without mass syndrome in terms of sensitivity for cholangiocarcinoma but does allow significantly higher cellularity abundance. <b>ClinicalTrials.gov ID: NCT04251013</b>