Emmett L, Buteau J, Papa N, et al. - A decrease in false negatives for clinically significant prostate cancer (csPCa) was seen with the combination of magnetic resonance imaging (MRI) + prostate-specific membrane antigen (PSMA) positron emission tomography, relative to MRI, thus potentially permitting a decrease in the number of prostate biopsies needed to diagnose csPCa.

• A prospective multicentre phase II imaging trial with 296 men with suspected prostate cancer, with no prior biopsy or MRI, recent MRI (6 mo), and planned transperineal biopsy based on clinical risk and MRI.

• 291 men had MRI, pelvic-only PSMA, and systematic ± targeted biopsy.

• Presence of csPCa was found in 56% (n = 162) of patients; 67% had PI-RADS (Prostate Imaging Reporting and Data System) 3–5, 73% were PSMA positive, and 81% were combined PSMA + MRI positive.

• Improved negative predictive value and sensitivity for csPCa were provided by PSMA + MRI in an MRI triaged population.

• Among all males, PSMA + MRI negative ones were 19% (56/291) (38% of PI-RADS 2/3) and could potentially have skipped biopsy, risking delayed csPCa diagnosis in 3.1% men with csPCa (5/162) or 1.7% (5/291) overall.