Background: To test clinically significant prostate cancer (csPCa) rates during follow-up in biopsy naïve patients that underwent two different diagnostic pathways: (1) SB GROUP (n = 354): systematic random biopsies (SB) vs. (2) TB GROUP (n = 264): multiparametric magnetic resonance imaging (mpMRI) and only targeted biopsies (TB) of PI-RADS ≥ 3 lesions. Patients with PI-RADS ≤ 2 score avoided prostate biopsies.
Methods: Retrospective single centre study of 618 biopsy naive patients (2015-2018). Two different definitions of csPCa were used: (1) csPCa ISUP GG ≥ 2 (ISUP grade group [GG] ≥ 2) and (2) csPCa ISUP GG ≥ 3. Kaplan-Meier plots and univariable Cox regression models tested rates over time of csPCa ISUP GG ≥ 2 and caPCa ISUP GG ≥ 3 in SB GROUP vs. TB GROUP.
Results: At initial biopsy, TB achieved higher rates of csPCa ISUP GG ≥ 2 (35.3 vs. 18.9%; p < 0.001) and csPCa ISUP GG ≥ 3 (12.6 vs. 6.2%; p = 0.04), relative to SB. After a median time follow-up of 36 months, the rates of csPCa ISUP GG ≥ 2 (6.1 vs. 4.4%; p = 0.6) and csPCa ISUP GG ≥ 3 (3.3 vs. 1.1%; p = 0.2) were similar in SB GROUP vs. TB GROUP. Moreover, in TB GROUP patients that avoided prostate biopsies because of negative baseline mpMRI (n = 145), only 4.1% exhibited csPCa ISUP GG ≥ 2 during follow-up. Moreover, none of these patients (PI-RADS ≤ 2) had csPCa ISUP GG ≥ 3.
Conclusions: In biopsy naïve setting, a diagnostic pathway including pre-biopsy mpMRI and TB of only PCa suspicious lesions is not associated with higher rates of csPCa during follow-up, relative to a diagnostic pathway of SB. Moreover, patients with negative baseline mpMRI could safely avoid prostate biopsies and could be followed with repeated PSA testing, since only a small proportion of them would harbor csPCa.