Peroral cholangioscopy with cholangioscopy-directed biopsies in the diagnosis of biliary malignancies: a systemic review and meta-analysis.

BACKGROUND AND AIM:Accurate diagnosis is essential in the appropriate management of biliary strictures. Our aim is to evaluate the efficacy of cholangioscopy-directed biopsies in differentiating biliary intraductal malignancies from benign lesions. MATERIALS AND METHODS:Articles were searched in Medline, PubMed, and Ovid journals. Pooling was performed by both fixed-effects and random-effects models. Only studies from which a 2×2 table could be constructed for true-positive, false-negative, false-positive, and true-negative values were included. RESULTS:Initial search identified 2110 reference articles for peroral cholangioscopy; of these, 160 relevant articles were selected and reviewed. Data were extracted from 15 studies (N=539) that fulfilled the inclusion criteria. Pooled sensitivity of cholangioscopy-directed biopsies in diagnosing malignancy was 71.9% [95% confidence interval (CI): 66.1-77.1] and pooled specificity was 99.1% (95% CI: 96.9-99.9). The positive likelihood ratio of cholangioscopy-directed biopsies was 18.1 (95% CI: 9.1-35.8), whereas the negative likelihood ratio was 0.3 (95% CI: 0.2-0.4). The pooled diagnostic odds ratio was 71.6 (95% CI: 32.8-156.4). All the pooled estimates calculated by fixed-effects and random-effect models were similar. Summary receiver operating characteristic curves showed an area under the curve of 0.98. The χ heterogeneity for all the pooled accuracy estimates was 5.62 (P=0.96). CONCLUSION:Peroral cholangioscopy with cholangioscopy-directed biopsies has a high specificity in differentiating intraductal malignancies from benign lesions. Cholangioscopy-directed biopsies should be strongly considered for biliary stricture evaluation.