Histologic retrieval rate of a newly designed side-bevelled 20G needle for EUS-guided tissue acquisition of solid pancreatic lesions

Background: Innovative approaches to improve diagnostic yield of endoscopic ultrasound-guided tissue acquisition (EUS-TA) have focused on needle design with development of fine-needle biopsy (FNB) needles with microcore-acquisition technology. Recently, a 20-gauge (20G) antegrade-cutting-side-bevelled biopsy needle (ProCore®) was developed for EUS-TA, but data about its diagnostic performance and histological capability are scant. Objectives: We assessed the diagnostic performance and histologic retrieval rate of a new 20G antegrade-cutting-side-bevelled biopsy needle compared with a 22G reverse-side-bevelled needle for EUS sampling of solid pancreatic lesions. Patients and methods: A retrospective analysis of 238 consecutively collected patients who underwent EUS-TA using a 20G or a 22G ProCore® needle, without rapid on-site evaluation (ROSE), was conducted at two centres.Sensitivity, specificity, positive predictive value and negative predictive value were calculated. Histologic tissue retrieval was evaluated applying a scoring system for each case. Results: Sensitivity and specificity were estimated as 98.4-100% in the 20G-, and 94.9-100% in the 22G-needle groups, respectively (p > 0.99). The 20G procured more histologic-grade tissues (92.6% vs 49.5%, p < 0.0001) achieved by a lower number of passes (2.64 vs 3.44, p < 0.0001) compared to the 22G. Conclusions: Both side-bevelled FNB needles achieved a high diagnostic sensitivity. The 20G-side-bevelled needle obtained a significantly higher microcore retrieval rate.