Accurate diagnosis of degree of atypia in cholangiocarcinoma by peroral cholangioscopy-guided probe-based confocal endomicroscopy

Prospective assessment of probe-based confocal laser endomicroscopy under direct cholangioscopic visualization for biliary strictures that could not be definitively diagnosed using endoscopic retrograde cholangiopancreatography (with video)

The definitive diagnosis of patients with indeterminate biliary strictures remains challenging. Probe-based confocal laser endomicroscopy (pCLE) provides real-time histological assessment of bile duct tissues. Since no previous studies have evaluated the efficacy of pCLE under direct cholangioscopic visualization for biliary strictures that cannot be definitively diagnosed through endoscopic retrograde cholangiopancreatography using fluoroscopy, we prospectively assessed the feasibility and safety of this procedure in three cases. pCLE findings were obtained in three cases, providing accurate diagnoses. Additionally, no adverse event was reported. pCLE under direct cholangioscopic visualization for indeterminate biliary strictures might be feasible and safe, even though these strictures were not previously diagnosed using endoscopic retrograde cholangiopancreatography. Further studies with more cases are warranted to clarify the effectiveness of pCLE under direct cholangioscopic visualization.

Diagnosis of Biliary Strictures Using Probe-Based Confocal Laser Endomicroscopy under the Direct View of Peroral Cholangioscopy: Results of a Prospective Study (with Video)

Background

The accurate diagnosis of biliary strictures remains problematic. The aim of the present study was to prospectively evaluate the clinical utility of probe-based confocal laser endomicroscopy (pCLE) under the direct view of peroral cholangioscopy (POCS) for the diagnosis of biliary strictures.

Methods

Consecutive patients with biliary strictures were included. We investigated sensitivity, specificity, and accuracy to diagnose malignancy for (1) ERCP alone, (2) POCS, (3) pCLE under the direct view of POCS, and (4) tissue sampling under the direct view of POCS.

Results

A total of 30 patients (17 with malignant lesions) were prospectively enrolled. (1) ERCP alone showed 88.2% sensitivity, 46.2% specificity, and 70% (95% confidence interval (CI), 52.1%–83.3%) accuracy. (2) POCS showed 100% sensitivity, 76.9% specificity, and 90% (95% CI, 74.4%–96.5%) accuracy. (3) pCLE under the direct view of POCS showed 94.1% sensitivity, 92.3% specificity, and 93.3% (95% CI, 78.7%–98.8%) accuracy. (4) Tissue sampling under the direct view of POCS showed 82.4% sensitivity, 100% specificity, and 90% (95% CI, 74.4%–96.5%) accuracy.

Conclusions

pCLE under the direct view of POCS provided highly accurate and sensitive characterization of biliary strictures and showed the potential for more diagnostic reliability and reduction of delays in diagnosis. This trial was registered at UMIN (registration number: UMIN000033801).