# Predictive impact of PI-RADS 3 lesion volume/total prostate volume ratio in prostate cancer diagnosis in biopsy-naïve patients

## TL;DR

This study explores how the ratio of PI-RADS 3 lesion volume to total prostate volume can help decide if a biopsy is needed for prostate cancer in patients who haven't had one before.

## Contribution

The study introduces the PI-RADS 3 ratio as a novel parameter to improve biopsy decision-making in prostate cancer diagnosis.

## Key findings

- The PI-RADS 3 ratio showed a statistically significant difference between benign and malignant groups.
- The optimal cut-off for the PI-RADS 3 ratio was 0.026 with 58.97% sensitivity and 66.96% specificity.
- A weak but significant relationship was found between PI-RADS 3 ratios and PSA density.

## Abstract

To assess the potential of the ratio between PI-RADS 3 lesion volume and total prostate volume as a predictive parameter for guiding the decision to perform a biopsy in patients presenting with PI-RADS 3 lesions on multiparametric prostate magnetic resonance imaging (mpMRI).

A total of 749 patients who underwent mpMRI due to suspected prostate cancer between January 2014 and August 2023 were scanned. Based on predefined inclusion and exclusion criteria, 308 patients were included. Age, total prostate-specific antigen (PSA) value, prostate volume measured in mpMRI, mpMRI result, PI-RADS 3 lesion volume, and biopsy results were collected. The PI-RADS 3 ratio was calculated as PI-RADS 3 lesion volume/total prostate volume. PSA density (dPSA) was calculated. The patients were categorized according to their biopsy results as benign or malignant (subclassified by Gleason group grade), and the two groups were compared.

The average PI-RADS 3 ratio was 0.032 ± 0.002. There were 230 (74.7%) patients in the benign group and 78 (25.3%) patients in the malignant group. There was a statistically significant difference detected in average prostate volumes (p < 0.001), dPSA values (p = 0.001), and PI-RADS 3 ratios (p < 0.001). The receiver operating curve analysis of PI-RADS 3 ratio indicated an area under the curve of 0.643 ± 0.037. The optimal cut-off point was 0.026 with a sensitivity of 58.97% and a specificity of 66.96%. A positive, albeit weak, statistically significant relationship was found between PIRADS-3 ratios and dPSA values (rs ρ = 0.261 and p < 0.001).

PI-RADS 3 ratio may serve as an auxiliary clinical parameter alongside age, dPSA, and lesion volume alone in identifying more refined candidates for biopsy in the goal of patient care individualization.