Comparison of MRI-guided in-bore and fusion biopsy for small pi-rads 4 prostate lesions

Abstract

Purpose We compared prostate cancer (PC) and clinically significant prostate cancer (csPC) identification performances of MRI-guided in-bore (IB) and software-fusion biopsy (SFB) techniques among small volume PI-RADS 4 index lesions. Methods We retrospectively reviewed 268 biopsy-na & iuml;ve patients with 308 small volume PI-RADS 4 index lesions (<= 7 mm in greatest dimension) on multiparametric prostate MRI and subsequent IB and SFB between January 2010 and December 2025. All IBs were performed by a single radiologist on 134 patients, while another radiologist and a urologist performed SFBs on the remaining 134 patients. Patient and lesion characteristics in both groups were analyzed. A multivariable binary logistic regression model was constructed to identify independent predictors of csPC. Results Median age was 67 in both cohorts. Median PSA value was 5.1 and 6 ng/ml, PSA density was 0.11 and 0.09 ng/ml/cm3 in IB and SFB cohorts, respectively. Among 308 PI-RADS 4 lesions <= 7 mm, PC was identified in 169 (54.9%) lesions, while csPC was identified in 94 (30.8%) lesions. IB technique revealed 60.1% and 41.9% PC and csPC among 148 lesions. SFB technique revealed PC and csPC rates of 50% and 20.6%, respectively, among 160 lesions. In-bore biopsy technique (p < 0.001), PSAD (p = 0.001) and number of cores (p = 0.010) were independent predictors of csPC on multivariate analysis. Conclusions Our study indicates that a significant proportion of small PI-RADS 4 index lesions may harbor csPC. Regarding small PI-RADS 4 lesions, IB technique was superior to SFB in detection of csPC.