Presentation Authors: Bertrand Covin*, Mathieu Roumiguié, Marie Laure Quintyn Ranty, Pierre Graff, Jonathan Khalifa, Richard Aziza, Guillaume Ploussard, Daniel Portalez, Bernard Malavaud, Toulouse, France
Introduction: To evaluate image-guided Transperineal Elastic-Registration biopsy (TPER-B) in the risk-stratification of low-to-intermediate risk prostate cancer detected by Transrectal-ultrasound biopsy (TRUS-B) when estimates of cancer grade and volume discorded with multiparametric Magnetic Resonance Imaging (MRI).
Methods: All patients referred for active surveillance or organ-conservative management were collegially reviewed for consistency between TRUS-B results and MRI. Image-guided TPER-B of the index target (IT) defined as the largest Prostate Imaging-Reporting Data System-v2 â‰¥3 abnormality were organized for discordant cases. Pathology reported Gleason grade, maximum cancer core length (MCCL) and total CCL (TCCL).
Results: Of 237 prostate cancer patients (1-7/2018), 42 were required TPER-B for risk-stratification. Eight cores were obtained [Median&IQR: 8 (6-10)] including five (IQR: 4-6) in the IT. TPER-B of the IT yielded longer MCCL [Mean&(95%CI): 5.4(3.9-6.9) vs. 2.5mm(1.9-3.1), p=0.002] and TCCL [16.7(10.6-22.8) vs. 3.9mm(3.1-4.8), p=0.0001] than TRUS-B of the gland. On TPER-B cores, longer TCCL [Mean&(95%CI): 28.9mm(19.1-38.7) vs. 12.3mm(4.8-19.7), p=0.02] were measured in Gleason score-7 than score-6 cancers (no cancers detected on IT TPER-B in 11 patients, all but one score 6 < 4mm on TRUS-B). TPER-B cores of the IT upgraded 16/42(38.1%) patients. 21/42(50.0%) met University College London-definition 1 (Gleason scoreâ‰¥4+3 and/or MCLâ‰¥6mm) and 27/42(64.3%) definition 2 (Gleason scoreâ‰¥3+4 and/or MCLâ‰¥4mm), which correlate to clinically significant cancers >0.5mL and >0.2mL, respectively. Allocation to higher risk groups than anticipated from TRUS-B spurred adaptation of treatment protocols (active surveillance n=15, prostatectomy n=11, ionizing radiation n=13, pending n=3).
Conclusions: Image-guided TPER-B of the index target provided more cancer material for pathology. Subsequent re-evaluation of cancer volume and grade switched a majority of patients towards higher risk groups and treatments with curative intent.