The predictive value of lesion density in enhancing multiparametric MRI for detecting clinically significant prostate cancer.

[PURPOSE] The aim of this study was to evaluate the predictive value of lesion density on mpMRI for detecting clinically significant prostate cancer (csPCa) in men undergoing targeted prostate biopsy.

[METHODS] We retrospectively analyzed patients who underwent MRI-targeted transperineal or transrectal biopsy between 2019 and 2023. Lesion density was calculated as longest lesion diameter divided by prostate volume, with weighted averages used for multiple lesions. Multivariable logistic regression and receiver operating characteristic (ROC) analysis assessed predictors of csPCa. Threshold analysis evaluated trade-offs between missed csPCa and avoided biopsies.

[RESULTS] csPCa was diagnosed in 241/460 patients (52.4%). Median lesion density was higher in csPCa vs. non-csPCa cases (0.34 mm/cc, IQR 0.22-0.52 vs. 0.22 mm/cc, IQR 0.14-0.33; P < 0.001). Lesion density was independently predictive in models with (OR 6.2, 95% CI 1.4-27.9) and without PI-RADS (OR 13.7, 95% CI 3.2-59.0). It achieved the highest AUC (0.71) compared with PSA density (0.69) and age (0.63). At a lesion density threshold of 0.15 mm/cc, 29.2% of biopsies would have been avoided with <10% missed csPCa.

[CONCLUSION] Lesion density was an independent predictor of csPCa on targeted biopsy. It may complement PI-RADS and PSA density and provide a pragmatic threshold-based tool to guide biopsy decision-making.