Clinical value of contralateral biopsies in men with unilateral MRI foci undergoing targeted biopsy

To evaluate the additional prostate cancer detection yield and clinical implications of performing contralateral systematic biopsies in men with unilateral suspicious magnetic resonance imaging (MRI) findings undergoing MRI-guided transperineal (TP) biopsies in an outpatient clinic.

A prospective study of 655 consecutive men with unilateral MRI suspicious findings undergoing office-based MRI-guided TP biopsies between May 2022 and December 2023. All men had pre-biopsy MRI followed by MRI-guided TP fusion biopsies with at least four targeted cores per lesion plus five contralateral systematic biopsies. The primary objective was the clinically significant prostate cancer (csPCa) detection rate of contralateral systematic biopsies in men with no or insignificant PCa on targeted biopsies. Secondary objectives included the impact of contralateral biopsies on PCa grade upgrading, additional insignificant PCa diagnoses, and the clinical implications of multifocal csPCa detected on both targeted and contralateral cores.

Any and csPCa (Gleason Grade Group [GG] ≥2) was detected in 564/655 (85%) and 471/655 (71%) men with a median age of 66 years and PSA level of 7.6 ng/mL. Overall, seven of 655 (1%) men had csPCa detected by contralateral systematic biopsies missed on MRI-targeted biopsy, all of whom had low-volume Gleason GG 2 PCa eligible for active surveillance. Furthermore, 70/464 (15%) men with csPCa on MRI-targeted biopsy had matching Gleason GG 2-5 PCa on contralateral biopsy, and another seven had higher Gleason GG. However, the additional information from contralateral biopsies did not seem to influence whole-gland treatment allocation and nerve-sparing during surgery.

Contralateral systematic biopsies in men with unilateral MRI findings undergoing MRI-guided TP targeted biopsies have limited value for csPCa detection and risk assessment for whole-gland treatment but may be important for determining PCa multifocality considering focal therapy eligibility.