Efficacy and safety of EUS-guided liver biopsy: a systematic review and meta-analysis

Background and Aims: EUS-guided liver biopsy (LB) is an emerging technique over conventional percutaneous (PC) or transjugular (TJ) approaches. Recent studies have reported that EUS-guided LB may have a better safety profile than PC LB or TJ LB without compromising diagnostic yield, and the outcomes are varied with respect to the types of biopsy needles. We performed a systematic review and meta-analysis to estimate the diagnostic yield, specimen adequacy, and adverse events associated with EUS-guided LB. Methods: We conducted a comprehensive search of multiple electronic databases and conference proceedings, including PubMed, EMBASE, and Web of Science databases (from inception to June 2018) to identify studies that reported on EUS-guided LB. The primary outcome was to estimate the pooled rates of successful diagnosis made and insufficient specimen obtained. The secondary outcome was to estimate the pooled rate of adverse events. A subgroup analysis compared the outcomes based on the type of biopsy needle. Results: A total of 9 study arms with 437 patients were included. The pooled rate of successful histologic diagnoses was 93.9% (95% confidence interval [CI], 84.9-97.7), with heterogeneity I-2 of 75.3%. The pooled rate of insufficient specimen obtained was 10.1% (95% CI, 3.5-25.8), with I-2 = 71.6%. The pooled rate of adverse events with EUS-guided LB was 2.3% (95% CI; 1.1-4.8, I-2 = 0). On subgroup analysis, the adverse events rate with a 19-gauge FNA needle (vs other core biopsy needles) was 0.9% (vs 2.7%, P = .28), and the rate of diagnostic yield was 95.8% (vs 92.7%, P = .59). The rate of insufficient specimen was significantly lower with an FNA needle compared with the core needle (4% vs 20%, P = .03). Conclusion: With a histologic diagnosis rate of 93.9% and adverse event rate of 2.3%, EUS-guided LB appears to be both effective and safe. A 19-gauge FNA needle provides significantly better biopsy specimens and seems to have better outcomes compared with other core biopsy needles.