Diagnostic Comparison of MRI/Ultrasound Fusion Biopsy and Systematic Biopsy in PI-RADS 4-5 Prostate Lesions

Objective: Multiparametric magnetic resonance imaging (mpMRI) has transformed prostate cancer (PCa) diagnosis by enabling lesion-targeted biopsies. The optimal biopsy approach—systematic biopsy (SB), MRI-ultrasound fusion targeted biopsy (TB), or their combination (CB)—remains debated, especially in patients with high-risk Prostate Imaging-Reporting and Data System (PI-RADS) 4-5 lesions. This study compared these strategies for detecting overall and csPCa. Methods: This retrospective study included 330 patients who underwent MRI-ultrasound fusion TB with 12-core SB between July 2022 and May 2025. Only lesions classified as PI-RADS v2.1 category 4 or 5 were analyzed. Detection rates of overall PCa and csPCa (Gleason score ≥ 7) were compared among SB, TB, and CB. Subgroup analyses were performed by PI-RADS category and lesion location (anterior, middle, posterior). Logistic regression identified independent predictors of csPCa. Results: A total of 429 lesions were evaluated. Overall, PCa detection rates were 62% for SB, 70% for TB, and 77% for CB (P < 0.001); the corresponding csPCa rates were 47%, 56%, and 63% (P < 0.001). TB detected csPCa more effectively than SB (56% vs. 47%, P < 0.01). PI-RADS 5 lesions had higher detection rates than PI-RADS 4 lesions across all methods. CB achieved the highest rates in all locations, especially in anterior and middle lesions. Age, positive digital rectal examination, prostate-specific antigen density, prior biopsy, and PI-RADS category 5 were independent predictors of csPCa. Conclusion: In PI-RADS 4–5 lesions, combined SB and TB provide the highest detection rate for csPCa. While TB improves selective detection, SB remains essential to avoid missing significant disease.