Score 3 prostate lesions: a gray zone for PI-RADS v2

Area of Science:

• Radiology
• Urology
• Oncology

Background:

• Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) lacks clear guidelines for PI-RADS v2 score 3 lesions.
• Distinguishing between indolent and significant prostate cancer in PI-RADS v2 score 3 lesions is clinically challenging.

Purpose of the Study:

• To evaluate the utility of biparametric MRI (bpMRI) lesion volume in managing PI-RADS v2 score 3 prostate lesions.
• To propose a refined management strategy for PI-RADS v2 score 3 lesions based on lesion volume.

Main Methods:

• Calculation of lesion volume using biparametric MRI (bpMRI) including T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI).
• Introduction of a 0.5 mL volume cut-off to stratify PI-RADS v2 score 3 lesions into low-risk (<0.5 mL) and high-risk (≥0.5 mL) subgroups.
• Proposed management: clinical surveillance for low-risk lesions and targeted biopsy for high-risk lesions.

Main Results:

• Lesion volume on bpMRI can effectively differentiate PI-RADS v2 score 3 lesions.
• Subgrouping allows for distinct management strategies, potentially reducing unnecessary biopsies by approximately 50%.
• The approach may increase the diagnostic yield for significant prostate cancer by approximately 30%.

Conclusions:

• Incorporating MRI lesion volume into PI-RADS v2 assessment can optimize the management of PI-RADS v2 score 3 lesions.
• This strategy aids radiologists in making more informed decisions, improving diagnostic accuracy and patient outcomes.
• Refined management of PI-RADS v2 score 3 lesions through volume assessment enhances clinical utility.