Slow-pull compared to suction technique for EUS-guided sampling of pancreatic solid lesions: a meta-analysis of randomized controlled trials

Background and study aims Current ESGE guidelines suggest employing the suction (SU) technique for endoscopic ultrasound (EUS)-guided sampling of pancreatic solid lesions. Nonetheless, recent randomized controlled trials (RCT) have reported that the slow-pull (SP) technique has similar diagnostic accuracy with possibly less blood contamination. However, these results are heterogeneous and limited to small cohorts. The aim of this meta-analysis was to compare adequacy, accuracy, sensitivity and specificity of the SU and SP techniques for EUS-guided sampling of solid pancreatic lesions. Methods A computerized bibliographic search was restricted to RCTs. Pooled effects were calculated using a random-effects model and expressed in terms of pooled sensitivity and specificity and OR (95 % CI) for adequacy and accuracy. Results Overall, seven RCTs were included, for a total of 475 patients (163 lesions sampled with SU, 164 with SP and 148 by both). The adequacy was similar (OR = 0.98) without heterogeneity (I2 = 0 %), but a high degree of blood contamination was more common with SU than SP (pooled rate 27.6 % vs 19.7 %). A non-significant superiority of SP in terms of pooled accuracy (OR = 0.82; 95 % CI 0.36–1.85) was recorded, with moderate heterogeneity (I2 = 52.4 %). The SP technique showed a slightly higher pooled sensitivity compared to SU (88.7 % vs 83.4 %), while specificity was similar (97.2 % SP vs 96.9 % SU), with considerable heterogeneity. Conclusion The current meta-analysis reveals non-superiority of SU over SP, while SP results in reduced blood contamination. If the 5 % accuracy difference favouring SP is true, with alfa error = 0.05 and beta = 0.20, a RCT of 982 patients per arm is needed to confirm significance.