Repeated prostate cancer screening using PSA testing and MRI in the STHLM-MRI trial

Addition of magnetic resonance imaging (MRI) to PSA testing has been proposed to enhance the benefit-to-harm ratio of prostate cancer screening, but data on repeated screening outcomes are lacking. A secondary analysis of the Swedish STHLM3-MRI randomized clinical trial of 1500 men who had a repeat test 2 to 3 years after the original prostate cancer screening, cancer with a Gleason score of 3 + 4 or greater was detected in 3% of men, and a tumor with a Gleason score of 6 was detected in less than 1%. A high proportion of the performed MRI scans lacked lesions that were suspicious for cancer. The authors conclude that in repeated prostate cancer screening, detection of clinically significant cancer was limited and detection of low-grade cancer remained low. These findings suggest that studies of strategies to reduce MRI-related resources use are needed.