PI-RADS v2 in Prostate Cancer and Correlation with T Staging, PSA Levels and ADC Values

Abstract

Background: Magnetic resonance imaging of the prostate is a major diagnostic tool in prostate cancer detection. In 2012, prostate imaging reporting and data system (PI-RADS) was published by the European society of urogenital radiology. Due to certain limitations in this version, arevised version namedProstate Imaging Reporting and Data System version 2 (PI-RADS v2) was proposed by the American College of Radiology in 2014 Objectives: To evaluate the role of multiparametric magnetic resonance imaging based prostate imaging reporting and data system (PI-RADS) version 2 for the assessment of peripheral zone prostate cancer and its correlation with the T staging, prostatic specific antigen (PSA) levels and apparent diffusion coefficient (ADC) values. Patients and Methods: Eighty seven patients underwent MRI at 1.5 T units. Dynamic contrast enhanced (DCE) imaging was done in 73 patients as 14 patients had deranged renal functions. Patients with a PI-RADS v2 score of ≥ 2 underwent biopsy except in one patient with a score of 1. The histopathological report was used as gold standard. T staging was done based on MRI. The score was correlated with T staging, ADC values and serum prostate-specific antigen (S.PSA) levels by two experienced blinded radiologists. Statistical analysis was done. Results: Highly significant correlation was observed between PI-RADS v2 score, T staging, ADC values and s PSA levels with P value < 0.005. DCE had added advantage in one patient only for up-gradation of score from 3 to 4. Conclusion: The dominant MR imaging sequence for the peripheral zone prostate cancer is diffusion weighted sequence and the corresponding ADC values, with the role of DCE sequences in doubtful cases only. PI-RADS v2 gives a scoring system on MRI for prostate cancer assessment. It should be routinely incorporated in the reporting protocol. Our study concluded that there is a highly significant correlation between lesion score on PI-RADS v2 with the T stage, corresponding ADC values and S.PSA levels, although larger study groups may be required for further evaluation and beyond doubt PI-RADS version 3 is already in its earliest stages.