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bpMRI can be used alternatively to mpMRI to detect and localize index prostate cancer.

Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) provides clinical guidelines for multiparametric magnetic resonance imaging (mpMRI) [T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)] of prostate. However, DCE-MRI seems to show a limited contribution in prostate cancer (PCa) detection and management. In our experience, DCE-MRI, did not show significant change in diagnostic performance in addition to DWI and T2WI [biparametric MRI (bpMRI)] which represent the predominant sequences to detect suspected lesions in peripheral and transitional zone (TZ). In this article we reviewed the role of DCE-MRI also indicating the potential contribute of bpMRI approach (T2WI and DWI) and lesion volume evaluation in the diagnosis and management of suspected PCa.

Biparametric Magnetic Resonance Imaging (bpMRI) of the prostate combining both morphologic T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) is emerging as an alternative to multiparametric MRI (mpMRI) to detect, to localize and to guide prostatic targeted biopsy in patients with suspicious prostate cancer (PCa). BpMRI overcomes some limitations of mpMRI such as the costs, the time required to perform the study, the use of gadolinium-based contrast agents and the lack of a guidance for management of score 3 lesions equivocal for significant PCa. In our experience the optimal and similar clinical results of the bpMRI in comparison to mpMRI are essentially related to the DWI that we consider the dominant sequence for detection suspicious PCa both in transition and in peripheral zone. In clinical practice, the adoption of bpMRI standardized scoring system, indicating the likelihood to diagnose a clinically significant PCa and establishing the management of each suspicious category (from 1 to 4), could represent the rationale to simplify and to improve the current interpretation of mpMRI based on Prostate Imaging and Reporting Archiving Data System version 2 (PI-RADS v2). In this review article we report and describe the current knowledge about bpMRI in the detection of suspicious PCa and a simplified PI-RADS based on bpMRI for management of each suspicious PCa categories to facilitate the communication between radiologists and urologists.

We have read with great interest the short communication by Turkbey and Choyke (1) in the September-October 2015 issue of Diagnostic and Interventional Radiology. The authors reported that Prostate Imaging Reporting and Data System (PIRADS) 2.0 provides extensive information on how to acquire, interpret, and report multiparametric magnetic resonance imaging (mpMRI) of the prostate and the highlights of the changes compared with PIRADS 1.0. However, there are some concerns to be discussed regarding the role of mpMRI and its limits in PIRADS.Current PIRADS 2.0 appears to have good diagnostic accuracy in prostate cancer (PCa) detection and localization, but standardizing the reporting of mpMRI exams and correlating it with tumor aggressiveness remain controversial (2). Dynamic contrast-enhanced (DCE)-MRI is a specific modality to detect PCa in the peripheral and transition zones and to correlate tumor aggressiveness and type of enhancement curves (3). DCE-MRI plays only a minor role in determining PIRADS assessment category, and each lesion gets a positive or negative score based on DCE-MRI (2). The gold standard for assessment of PCa aggressiveness is the Gleason score obtained from prostate biopsy or radical prostatectomy specimens.Furthermore, other limits to be considered for the mpMRI include the cost and the time required to complete the study, such as the use of gadolinium-based contrast agents requiring intravenous access and different technical parameters (e.g., field strength and b values).In the diagnosis of PCa, it is essential to consider that: 1) Histopathology remains the gold standard method for diagnosis of PCa; 2) Dominant sequences in the lesion detection are diffusion-weighted imaging (DWI) and T2-weighted MRI; 3) DCE-MRI has a secondary role to T2-weighted MRI and DWI, and it is often difficult to differentiate focal enhancement of small PCa (especially in the transition zone) from adjacent normal prostatic tissues; and 4) T2-weighted MRI alone or with DWI is sufficient for MRI-ultrasonography fusion to direct biopsy needles under transrectal ultrasound guidance. Considering the abovementioned points, in patients suspected of having PCa, the goals of MRI are essentially detection, localization, and staging of the lesions suspected for PCa.We use biparametric MRI (bpMRI) at 3.0 T with nonendorectal coil incorporating axial fat suppression T1-weighted MRI, axial, sagittal, and coronal T2-weighted MRI and DWI series with apparent coefficient diffusion (ADC) maps. In our experience, we consider DWI as the dominant sequence in lesion detection both in the peripheral and transition zones and in the anterior fibromuscular stroma (Fig.), as reported (4). In addition to DWI/ADC, we consider the appearance of the lesions on T2-weighted MRI to prevent overcalling in the transition zone.Currently, there is no prospective randomized study that evaluates role of bpMRI for detection of PCa. The current limited experience is all based on retrospectively evaluated data. The real impact of DCE-MRI and/or use of ...