Prostate cancer: diagnostic yield of modified transrectal ultrasound-guided twelve-core combined biopsy (targeted plus systematic biopsies) using prebiopsy magnetic resonance imaging.

Purpose: This study aimed to analyze the diagnostic yield of modified transrectal ultrasound (TRUS)-guided 12-core combined biopsy (CB) using prebiopsy magnetic resonance imaging (MRI) for detecting clinically significant prostate cancer (csPCa).

Methods: This retrospective study included 130 consecutive patients who underwent modified TRUS-guided 12-core CB using cognitive fusion for lesions of Prostate Imaging-Reporting and Data System (PI-RADS) category ≥ 3. The 12-core CB comprised 3-6-core targeted biopsy (TB) and systematic biopsy (SB). For SB, tissue sampling in TB regions was omitted, and 3-core sampling (i.e., apex, mid, and base) in the contralateral peripheral zone of TB was mandatory. csPCa was defined as International Society of Urological Pathology (ISUP) grade ≥ 2 cancer. The per-patient cancer detection rates (CDRs) according to biopsy type or PI-RADS category were investigated.

Results: The CDRs of TB, SB, and CB for csPCa were 47.7% (62/130 patients), 29.2% (38/130), and 52.3% (68/130), respectively. For csPCa, the CDRs of TB and CB according to PI-RADS categories of 3, 4, or 5 were 25.0% (8/32) and 31.3% (10/32), 41.2% (28/68) and 45.6% (31/68), or 86.7% (26/30) and 90.0% (27/30), respectively. In 6 (4.6%) patients, csPCa was detected only by SB. In 18 (13.8%) patients, SB detected PCa of a higher ISUP grade than TB. In 11 (8.5%) patients, SB detected csPCa at contralateral peripheral zone of TB.

Conclusion: Modified TRUS-guided 12-core CB using prebiopsy MRI seems to be feasible. It may reduce total biopsy cores in patients who are suitable for CB based on prebiopsy MRI findings.