Higher diagnostic accuracy of multiparametric MRI using PI-RADSv2 for transitional zone prostate lesions compared to peripheral zone prostate lesions
Sara Fardin, Michael Nguyentat, Shane Knipping, Alexander Ushinsky, Layla Shirkhoda, Alessandra Miranda Aguirre, Christopher Green, Edward Uchio, Chandana Lall and Roozbeh Houshyar
University of California, Irvine, USA
: J Clin Exp Oncol
Introduction: Multiparametric MRI (mpMRI) utilizing PI-RADSv2 has been recently validated as an adjunct tool to screen for prostate cancer, regardless of location. Our study compares the diagnostic accuracy of PI-RADSv2 for transitional zone (TZ) and peripheral zone (PZ) prostate lesions. Utilizing radiologic-pathologic correlation through mpMRI and a combination of TRUS guided 12-core and MRI/TRUS fusion biopsies, we compared the diagnostic accuracy of mpMRI utilizing PI-RADSv2 for detecting clinically significant cancer in the TZ versus the PZ of the prostate. Methods: We retrospectively reviewed charts of patients with prostate mpMRI, and subsequent combination biopsy (TRUS-guided 12-core biopsy plus MRI/TRUS fusion biopsy). 136 men with a total of 231 mpMRI lesions were identified. Spearmanâs correlation, chi-square and ROC analyses were performed. Results: There was positive correlation between PI-RADSv2 and Gleason scores (p < 0.001) in both PZ and TZ. For clinically significant cancer in PZ, mpMRI had an NPV, PPV, sensitivity and specificity of 100%, 31.6%, 100% and 9%, respectively, compared to 100%, 27.1%, 100% and 41.1%, respectively, for TZ lesions. For clinically significant cancer, the PI-RADSv2 AUC for PZ lesions was 0.769 (95% CI 0.684â0.854, p< 0.001), compared to AUC=0.844 (95% CI 0.753â0.935, p< 0.001) for TZ lesions. Discussion: MpMRI utilizing PI-RADSv2 achieves an excellent sensitivity and NPV for both PZ and TZ prostate lesions. However, compared to PZ lesions, PI-RADSv2 scores for TZ lesions have a higher specificity and also had a 0.120 larger AUC, indicating a higher diagnostic accuracy for TZ prostate lesions.
Sara Fardin has completed her Medical School in Tehran University of Medical Sciences and Radiology-Molecular Imaging Research Fellowship in the University of Pennsylvania. She is currently working as a Research Fellow in University of California, Irvine.