(UroToday.com) The 2025 AUA annual meeting featured an engineering and urology session and a presentation by Dr. Eric Gwynn discussing a novel core needle biopsy instrument designed for targeted biopsy. Adoption of targeted prostate biopsy is accelerating due to increased detection of clinically significant prostate cancer. However, two significant phenomena with the existing standard of care needles impede maximum sampling of the target: needle deflection and tissue displacement. Standard of care needles capture tissue in a notch located just proximal to the tip of the needle. Several studies have reported deflection of the needle tip as it traverses tissues of varying density, which impedes accurate sampling of target areas and reduces the volume of tissue captured within the notch. The second is the shock wave generated by the needle when fired, which displaces tissues surrounding it. A novel core needle biopsy instrument addresses both phenomena, which is coaxially centered in the outer cannula to prevent deflection:
To compensate for tissue displacement when the needle is fired, the novel biopsy gun is designed to cause the needle to recoil twice when it reaches the end of its travel. A second feature delays deployment of the outer cannula by 5-8 msec after the needle reaches the end of its travel:
This study, presented at the AUA 2025 annual meeting, reported on five men undergoing MRI fusion ultrasound guided transperineal targeted biopsies enrolled in a multicenter randomized study (NCT05470127). Tissue deflection in a limited series of consecutive targeted biopsies was measured from a frozen ultrasound image following sample acquisition. Measurement was from the tip of the needle at the end of its travel to the intended needle path:
The standard of care instrument deflected 18 times out of 28 firing attempts (64%), whereas the novel instrument was only 2 out of 25 (8%). Standard of care needle deflections ranged from 1- 4 mm off target, with a mean of 1.8 mm, and both deflections from the novel instrument were 1 mm. Two tailed Z test comparing percentages of deflection resulted in a Z value of 4.22, p < 0.00001. Two tailed t test comparing mean deflection resulted in a t value of 1.6752, p < 0.00003:
Dr. Gwynn concluded his presentation discussing a novel core needle biopsy instrument designed for targeted biopsy with the following take home points:
- In this comparison of needle deflection in targeted prostate biopsy, the novel biopsy instrument performed significantly better than the standard of care instrument in terms of frequency of deflection and distance from the target
- Accuracy in targeting suspected lesions may impact cancer detection rates
- These promising results are being investigated in a large multicenter study
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Associate Professor of Urology, Georgia Cancer Center, Wellstar MCG Health, @zklaassen_md on Twitter during the American Urological Association's 2025 Annual Meeting, between April 26 – 29, 2025, in Las Vegas, NV.
Related Content: The Details Are in the Core: Advancing Prostate Tissue Collection - James Wysock