Precision Matters in MR Imaging–targeted Prostate Biopsies: Evidence from a Prospective Study of Cognitive and Elastic Fusion Registration Transrectal Biopsies

Abstract

Purpose To measure the precision in placement of a biopsy needle in a magnetic resonance (MR) imaging-detected target with transrectal ultrasonography (US), to document the clinical relevance of precision, and to report on the precision of cognitive and software-based registrations. Materials and Methods This prospective study was approved by the institutional review board and performed between June 2013 and September 2013. Patients provided informed verbal consent. Two cores each were obtained with cognitive and fusion techniques in 88 patients with a Prostate Imaging Reporting and Data System version 1 score of at least 3. Precision was measured with Euclidian geometry by using the Digital Imaging and Communications in Medicine archives of the biopsy as the distance from the core to the center (dCC) and the distance from the core to the surface of the target modeled as a sphere. To address clustering of data from multiple cores in the same patients, analyses of precision focused on the best shot for a patient or a technique. The Welch unequal variance t test and Yates corrected χ test were used as appropriate. Results Mean precision was 2.5 mm (95% confidence interval: 1.8 mm, 3.3 mm). Positive cores were closer to the center than were negative cores (dCC: 1.7 mm vs 3.1 mm, respectively; P = .025). More cancers were detected with on-target than off-target cores (33 of 71 cores [46.5%] vs three of 17 cores [17.6%]; P = .03). Cores obtained with the fusion technique achieved a higher precision than did cores obtained with the cognitive technique (dCC: 2.8 mm vs 7.1 mm, respectively; P < .0001). Targeted cores demonstrated cancer in 44 patients. Fewer cancers were detected with the cognitive technique than with the fusion technique (31 of 44 patients [70.5%] vs 40 of 44 patients [90.9%]; P = .03). Conclusion A deformable MR imaging/transrectal US image registration system achieved a higher precision and depicted cancer in more patients than did the cognitive freehand technique. RSNA, 2018.

Needle Biopsy Adequacy in the Era of Precision Medicine and Value-Based Health Care

“…258,259 To enhance adequacy, much effort has been made to improve the approach route for needle biopsy 260,261 and, in needle design, to increase core length. 255 Accuracy of needle targeting is affected by mode of imaging guidance 262 and by tip deflection, which in turn is affected by prostate size and tissue texture. 263…”

Tracked Foley catheter for motion compensation during fusion image-guided prostate procedures: a phantom study

“…FBx highlights the benefits that fusionguided procedures may offer patients; however, challenges and limitations remain. Currently, outcomes for image-guided prostate biopsy and focal ablation are highly dependent upon accurate needle placement at an exact target location [7,8,[10][11][12][13][14]. Semi-automated computer navigation and guidance allow for the registration (alignment/matching) of pre-procedural imaging (i.e, mpMRI) with real-time intra-procedural imaging (i.e, US).…”

Editorial Comment from Dr Ukimura to Magnetic resonance imaging/transrectal ultrasonography fusion targeted prostate biopsy finds more significant prostate cancer in biopsy‐naïve Japanese men compared with the standard biopsy

“…Targeted biopsy with deformable magnetic resonance/transrectal ultrasonography (MR/TRUS) image registration system was able to improve the detection of clinically significant prostate cancer (csPCa) by reducing the number of clinically insignificant prostate cancer detections compared with systematic biopsy …”

“…More importantly, the various experts for targeted biopsy have likely reported that as long as they carry out the targeted biopsy with MR/ultrasonography image fusion, image visibility of the target in not only MRI, but also TRUS is important to improve the detection rate of csPCa . Interestingly, a deformable MR/TRUS image registration system achieved a higher precision in placement of a biopsy needle in the MRI‐detected target with TRUS …”