Aim of this study was to compare the diagnostic performance of PI-RADS version 1 (v1) and version 2 (v2) in the detection of prostate cancer (PCa).
Multiparametric MRIs (mpMRI) of 50 consecutive patients with biopsy proven PCa, which had originally been evaluated according to PIRADS v1, were now retrospectively re-evaluated, comparing PI-RADS v1 and v2. MpMRI data were evaluated in comparison with histopathological whole-mount step-section slides. MRI examinations included T2-weighted, diffusion-weighted, and dynamic contrast-enhanced MRI.
Overall PI-RADS v1 showed a significantly larger discriminative ability of tumor detection: PI-RADS v1 AUC 0.96 (95 % CI 0.94-0.98) and v2 AUC 0.90 (95 % CI 0.86-0.94). For peripheral zone lesions, PI-RADS v1 showed a significantly larger ability of PCa discrimination: v1 AUC 0.97 (95 % CI 0.95-0.99) and v2 AUC 0.92 (95 % CI 0.88-0.96). For transition zone lesions, PI-RADS v1 showed more discrimination: v1 AUC 0.96 (95 % CI 0.92-1.00) and v2 0.90 (95 % CI 0.83-0.97), but the difference was not significant. PI-RADS v2 resulted in significantly more false negative results (3 % in v1, 14 % in v2) and a comparable number of true positive results (82 % in v1, 80 % in v2).
PI-RADS v2 uses a simplified approach, but shows a lower diagnostic accuracy. This could lead to a higher rate of false negative results with the risk of missing tumors within low PI-RADS score levels. Therefore, its use cannot be recommended unconditionally, and further improvement should be considered.
World journal of urology. 2016 Aug 10 [Epub ahead of print]
Thomas Auer, Michael Edlinger, Jasmin Bektic, Udo Nagele, Thomas Herrmann, Georg Schäfer, Friedrich Aigner, Daniel Junker
Department of Radiology, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria., Department of Medical Statistics, Informatics, and Health Economics, Medical University of Innsbruck, Schöpfstraße 41/1, 6020, Innsbruck, Austria., Department of Urology, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria., Landeskrankenhaus Hall, Abteilung für Urologie und Andrologie, Milser Straße 10, 6060, Hall in Tirol, Austria., Klinik für Urologie und Urologische Onkologie, Medizinische Hochschule Hannover, Carl-Neuberg-Straße 1, 30625, Hannover, Germany., Department of Pathology, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria., Department of Radiology, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria., Department of Radiology, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria. .