Deferring prostate biopsy after magnetic resonance imaging: evidence-graded thresholds for men with suspected prostate cancer – a narrative review

Magnetic resonance imaging (MRI) before biopsy has replaced systematic transrectal ultrasound-guided sampling as the first diagnostic step for men with suspected prostate cancer; the open question is which men can safely forgo biopsy after imaging. This narrative review synthesised randomised trials, paired diagnostic studies, screening trials and meta-analyses identified from 441 unique PubMed records searched to September 2026 (45 sources cited) to derive evidence-graded thresholds for deferring biopsy. A non-suspicious MRI (Prostate Imaging Reporting and Data System [PI-RADS] score 1–2) had a pooled negative predictive value of 90.8% (95% confidence interval [CI] 88.1–93.1) for grade group 2 or higher cancer across 42 studies and 7321 biopsy-naive men: about nine significant cancers are missed per 100 men not biopsied. With a prostate-specific antigen (PSA) density below 0.15 ng/mL/mL as well, subsequent incidence was close to that of the general population (rate ratio 1.4, 95% CI 0.9–2.0). PI-RADS 3 lesions had a pooled positive predictive value of about 13%; density thresholds of 0.10–0.20 ng/mL/mL missed 1–14 significant cancers per 100 men spared, depending on threshold and prevalence. In screening, biopsying only MRI-positive men roughly halved overdiagnosis (relative risk 0.46, 95% CI 0.33–0.64) without a detectable rise in significant cancer, whereas omitting systematic cores in MRI-positive men reduced significant-cancer detection. Transperineal biopsy reduced infection-related admission. Biopsy can be deferred safely only when a negative or equivocal MRI is combined with a low PSA density and a defined plan of repeat PSA testing and imaging.