Combination of ERCP-Based Modalities Increases Diagnostic Yield for Biliary Strictures

Background Biliary stricture evaluation with brush cytology and intraductal forceps biopsy carries a low sensitivity, but the combination of newer modalities may improve sensitivity. Aim To determine whether the addition of advanced modalities increases diagnostic yield of ERCP-based sampling. Methods This single-center retrospective study evaluates patients with biliary strictures sampled using brush cytology. Operating characteristics were calculated for individual and combinations of modalities including cholangioscopy, fluoroscopy- and cholangioscopy-directed intraductal biopsy, fluorescence in situ hybridization (FISH), and confocal laser endomicroscopy. Analyses under Standard Criteria (SC) included malignant results as positive and Expanded Criteria (EC) included suspicious and high-grade dysplasia results as positive. Results A total of 614 patients were included, and 354 (57.8%) received brush cytology alone, which had a sensitivity of 38.5% (SC) to 40.3% (EC) and a specificity of 97.8% (EC) to 99.3% (SC). Combining brush cytology with fluoroscopy-guided biopsy (n = 259, 42.2%) had a sensitivity of 62.5% (SC) to 67.9% (EC) and specificity of 90.2% (EC) to 96.7% (SC). Adding FISH to brush cytology had a sensitivity of 84.2% (SC) to 87.5% (EC) and specificity of 54.1% (SC and EC), while cholangioscopy visualization addition resulted in a sensitivity of 80.4% (SC) to 92.2% (EC) and specificity of 67.3% (EC) to 89.1% (SC). There were no significant differences in sensitivity and specificity using SC and EC. Conclusions Brush cytology has a low sensitivity, but the addition of other modalities increases sensitivity. There was no difference in specificity between the SC and the EC, supporting the inclusion of suspicious impressions with malignant results at our center.

Automated summary

The study showed that brush cytology has low sensitivity, but adding other modalities can increase diagnostic sensitivity. There was no difference in specificity between including suspicious impressions with malignant results.