Case Western Reserve University School of Medicine
Introduction: The evidence supporting multiparametric magnetic resonance imaging (mpMRI) targeting for biopsy is nearly exclusively based on biopsy pathologic outcomes. This is problematic, as targeting likely allows the preferential identification of small high-grade areas of questionable oncologic significance, raising the likelihood of overdiagnosis and overtreatment. We estimate the impact of MRI-targeted, systematic, and combined biopsies on radical prostatectomy (RP) grade group concordance. Methods: PubMed MEDLINE and Cochrane Library were searched from July 2018 - January 2022. Studies that conducted systematic and MRI-targeted prostate biopsies and compared biopsy results with pathology after RP were included. We performed a meta-analysis to assess whether pathologic upgrading and downgrading was influenced by biopsy type and a net-benefit analysis using pooled risk-difference (RD) estimates. Results: Both targeted and combined biopsies were less likely to result in upgrading (odds ratio [OR] vs. systematic of 0.70 (95% CI 0.63-0.77, p < 0.001 and 0.50, 95% CI 0.45-0.55, p < 0.001), respectively). Combined biopsy doubled the odds of downgrading (1.96, 95% CI, 1.68- 2.27, p<0.001) compared to systematic biopsies (15% vs. 9.0%). Net benefit of targeted and combined biopsies is 8 and 7 per 100 if harms of up- and downgrading are considered equal, but 7 and -1 per 100 if the harm of downgrading is considered twice that of upgrading. Conclusions: Combined MRI- and systematic biopsies are associated with less upgrading but more downgrading at RP. Our findings highlight a potential net-harm of performing combined MRI-targeted and systematic biopsies if pathologic downgrading is considered more detrimental than upgrading at prostatectomy. Strong heterogeneity suggests further research into factors that influence rates of up- and downgrading and should distinguish clinically relevant from irrelevant grade changes. SOURCE OF Funding: N/A
