Single-operator cholangioscopy and targeted biopsies in the diagnosis of indeterminate biliary strictures: a systematic review

Background and Aims: Evaluation of indeterminate biliary strictures by brush cytology and intraductal biopsies is limited by low sensitivity. The utility of SpyGlass peroral cholangioscopy for diagnosis of malignant biliary strictures and cholangiocarcinoma (CCA), in particular, remains unclear. Our aim was to study the utility of SpyGlass peroral cholangioscopy and targeted biopsy for diagnosis of malignant biliary strictures and CCA. Methods: In this systematic review, PubMed and Embase databases were reviewed for studies published to October 2014. The main outcomes of interest were sensitivity, specificity, and diagnostic odds ratio (DOR) of SpyGlass cholangioscopy in the diagnosis of malignant biliary strictures. Results: The search yielded 10 studies involving 456 patients. The pooled sensitivity and specificity of cholangioscopy-guided biopsies in the diagnosis of malignant biliary strictures was 60.1% (95% confidence interval [CI], 54.9%-65.2%) and 98.0% (95% CI, 96.0%-99.0%), respectively. The pooled DOR to detect malignant biliary strictures was 66.4 (95% CI, 32.1-137.5). Four studies included patients who had previous negative imaging and brushings and/or intraductal biopsies. Among these 4 studies, the pooled sensitivity and specificity for diagnosis of malignant biliary strictures was 74.7% (95% CI, 63.3%-84.0%) and 93.3% (95% CI, 85.1%-97.8%), respectively. The pooled DOR was 46.0 (95% CI, 15.4-138.1). Only 1 study directly compared the yield of SpyBite biopsies with standard brushings and biopsies. SpyBite biopsies had a sensitivity of 76.5% compared with brushings (5.8%) and biopsies (29.4%). Six studies specifically reported the role of cholangioscopy with targeted biopsies in the diagnosis of CCA. The pooled sensitivity and specificity to detect CCA was 66.2% (95% CI, 59.7%-72.3%) and 97.0% (95% CI, 94.0%-99.0%), respectively. The pooled DOR to detect CCA was 79.7 (95% CI, 32.7-194.7). Conclusions: Our study suggests that SpyGlass cholangioscopy with SpyBite biopsies has moderate sensitivity for the diagnosis of malignant biliary strictures.