Pathologic evaluation of a new endoscopic ultrasound needle designed to obtain core tissue samples: A pilot study

Background and Objectives: Standard endoscopic ultrasound-fine-needle aspiration (EUS-FNA) needles are in widespread use. Meaningful differences between the available needles have been difficult to identify. Recently, a new EUS needle (Shark Core®, Covidien, Dublin, Leinster, Ireland), has been introduced in an attempt to improve diagnostic accuracy, tissue yield, and to potentially obtain a core tissue sample. We performed a pilot study prospectively to evaluate this new needle when compared to a standard EUS-FNA needle. Materials and Methods: Analysis of the first 15 patients undergoing EUS-FNA with the Shark Core needle was performed and it was compared to EUS-FNA in 15 patients who underwent EUS-FNA with a standard needle. Results: The Shark Core needle required fewer needle passes to obtain diagnostic adequacy than the standard needle [(x²(1) = 11.3, P < 0.001]. The Shark Core needle required 1.5 passes to reach adequacy, whereas the standard needle required three passes. For cases with cell blocks, the Shark Core needle produced diagnostic material in 85% of cases [95% confidence interval (CI): 54-98], whereas the standard needle produced diagnostic material in 38% of the cases (95% CI: 9-76). The Shark Core needle produced actual tissue cores 82% of the time (95% CI: 48-98) and the standard needle produced no tissue cores (95% CI: 0-71) (P = 0.03). Conclusion: This pilot study found that the Shark Core needle had a high rate of producing adequate cytologic material for the diagnosis of pancreatic and peri-pancreatic lesions sampled by EUS with fewer passes required to obtain a definitive diagnosis and with a high rate of tissue cores being obtained when compared to a standard FNA needle.