Efficacy of Biliary Brush Cytology With Rapid On-Site Cytological Evaluation for the Detection of Malignant Biliary Strictures

Background and Aims

Brush cytology is a widely used diagnostic method in conjunction with intraductal biopsies during endoscopic retrograde cholangiopancreatography, but its diagnostic yield remains a limitation. This study evaluated the efficacy of biliary cytology using a newly developed brush device with rapid on-site cytological evaluation (ROSE) for detecting malignant biliary strictures (MBSs).

Methods

In total, 58 patients with suspected intrinsic MBS identified by intraductal ultrasound were enrolled. After achieving tissue sampling with ROSE through a maximum of two brushing passes, a transpapillary forceps biopsy (TPB) was performed. The primary outcome was diagnostic accuracy, and the secondary outcomes were technical success, sampling adequacy, and procedure-related adverse events.

Results

Biliary cytology with ROSE was technically successful in all patients (58/58), with a sampling adequacy of 96.6% (56/58). The technical success and sampling adequacy of TPB were 94.8% (55/58) and 91.4% (53/58), respectively. Brush cytology with ROSE and TPB yielded sensitivity rates of 91.8% and 85.7%, specificity rates of 88.9% for both, and accuracy rates of 88.9% for both. The receiver operating characteristic curve comparing the diagnostic accuracies of brush cytology with ROSE and TPB combined versus TPB alone showed a significantly higher value for the combined approach (0.93) than TPB alone (0.87) (p = 0.010).

Conclusion

Biliary brush cytology using a novel brush device with ROSE is effective and can be used complementarily to TPB in patients with suspected MBS.