Effect of the number of passes on diagnostic performance of EUS fine-needle biopsy of solid pancreatic masses: a systematic review and meta-analysis

Background and aims: The optimal number of passes to maximize the diagnostic ability of EUS fine-needle biopsy (FNB) of solid pancreatic masses (SPMs) is not well known. We conducted a systematic review to evaluate the impact of the incremental number of passes on diagnostic accuracy, tissue adequacy, and diagnostic yield for EUS-FNB of SPMs.

Methods: We searched MEDLINE, Embase, Scopus, and Cochrane Central for randomized controlled trials comparing per-pass diagnostic outcomes of FNB needles in patients with SPMs. Meta-analysis was conducted using random-effects models. A separate analysis was performed on studies that used contemporary Franseen and fork-tip needles.

Results: Overall, 19 randomized controlled trials (N = 3552) were identified. For EUS-FNB of SPMs, 3 passes with any FNB needle outperformed 2 passes for accuracy (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.20-2.09; I² = 0%), adequacy (OR, 1.97; 95% CI, 1.30-2.83; I² = 61%), and yield (OR, 2.12; 95% CI, 1.37-3.27; I² = 14%). Adding a fourth or fifth pass resulted in no significant improvement in diagnostic parameters. When using contemporary FNB needles, adding a second to a single pass significantly improved accuracy (OR, 1.80; 95% CI, 1.23-2.63; I² = 0%), adequacy (OR, 2.19; 95% CI, 1.65-2.90; I² = 0%), and yield (OR, 2.72; 95% CI, 1.50-4.95; I² = 0%). Adding a third pass to a second pass with contemporary needles improved adequacy (OR, 2.96; 95% CI, 1.97-4.46; I² = 0%) but did not provide better diagnostic accuracy or yield.

Conclusions: Two passes with Franseen or fork-tip needles and 3 passes with any FNB needle suffice to provide optimal diagnostic performance for EUS-FNB of SPMs, without additional diagnostic benefits with more passes. Our results can inform future guidelines and quality benchmarks.