Factors associated with higher prostate biopsy yield: when is software-assisted fusion MRI-targeting necessary?

Objective: To evaluate the addition of software-assisted fusion magnetic resonance imaging (MRI) targeted biopsy to systematic biopsy and determine clinical and imaging factors associated with improved prostate cancer (PCa) detection. Methods: We analyzed 454 patients who had prostate MRI and underwent combined systematic and software-assisted fusion MRI-targeted biopsy at 2 academic centers between July 2015 and December 2017. For our analysis, we compared the Gleason grade group of cores obtained systematically to cores obtained using MRI-targeting. Using multivariable analysis, we examined clinical and imaging factors associated with higher grade group disease in MRI-targeted cores. Results: Software assisted fusion MRI-targeted biopsy detected higher grade group disease in 18.3% of patients. Factors associated with higher grade group disease in MRI-targeted cores included anterior MRI lesion location (odds ratio [OR] 3.15, P< 0.01) and multiple lesions on MRI (OR 2.47, P = 0.01). Increasing prostate volume per cubic centimeter was noted to be negatively associated (OR 0.98, P = 0.02). Notably, factors not found to be associated with improved detection included PIRADS classification 5 compared to 3 (OR 2.47, P = 0.08), PIRADS classification 4 compared to 3 (OR 1.37, P = 0.50), previous negative biopsy (OR 1.48, P = 0.29), inclusion on an active surveillance protocol (OR 1.36, P = 0.48), transitional zone lesion location (OR 0.72, P = 0.45), and institution at which biopsy was performed (OR 1.81, P = 0.16). Conclusion: Adding software-assisted fusion MRI-targeting to systematic prostate biopsy offers benefit for men with an anterior and multiple MRI lesions. In absence of these factors, systematic biopsy alone or with cognitive fusion may be considered.