Who Can Avoid Systematic Biopsy Without Missing Clinically Significant Prostate Cancer in Men Who Undergo Magnetic Resonance Imaging-Targeted Biopsy?

Background: The objective of the study was to identify a subset of men who can avoid systematic multisite biopsy (SyB) among those undergoing magnetic resonance imaging (MRI)-targeted transperineal 4-core biopsy (TgB) without missing clinically significant cancer (SC).

Patients and methods: From April 2013 to December 2017, 304 men with elevated prostate-specific antigen levels (< 20 ng/mL) or abnormal digital rectal examination and positive MRI findings underwent transrecta ultrasound and MRI-targeted transperineal 4-core with 14-core systematic biopsy. MRI findings were prospectively collected and evaluated using Prostate Imaging-Reporting and Data System version 2 (PI-RADS), and scores ≥3 were considered positive. SC was defined as Gleason score ≥3 + 4 or maximum cancer length ≥5 mm. We evaluated the diagnostic performance of TgB and SyB to detect SC and characterized men who could avoid SyB without missing SC.

Results: Detection rates of any cancer and SC for TgB/SyB/their combination were 59%/63%/68% and 51%/52%/61%, respectively. TgB alone missed 14% (29/207) of any cancer and 16% (29/184) of SC detected using TgB with SyB. In uni- and multivariable analyses, PI-RADS scores of 3 to 4 were independent predictors for missing SC using TgB alone. When restricted to 81 men with PI-RADS scores of 5 (27%), SC was missed using TgB alone only in 3 (4.6% vs. 22% for the remaining 223 men; P = .007).

Conclusion: SC was missed using TgB alone in a non-negligible proportion of men who underwent TgB and SyB. SyB might be safely avoided in men with PI-RADS score 5 lesions with reduced risks of missing SC.