Prostate Cancer Screening with Magnetic Resonance Imaging: Results from the Second Round of the Göteborg Prostate Cancer Screening 2 Trial

BACKGROUND: The Göteborg 2 prostate cancer (PC) screening (G2) trial evaluates screening with prostate-specific antigen (PSA) followed by magnetic resonance imaging (MRI) in case of elevated PSA levels. OBJECTIVE: To assess the safety of using a 2-yr interval in men who were previously screened positive with PSA but had negative MRI or positive MRI with a negative biopsy. DESIGN, SETTING, AND PARTICIPANTS: A total of 61 201 men aged 50-60 yr were randomized and 38 366 were invited for screening (years 2015-2020). Men with positive MRI (Prostate Imaging Reporting and Data System [PI-RADS] score ≥3) were scheduled for targeted biopsies. Men with negative MRI or negative biopsies were reinvited after 2 yr. Round 1 and 2 MRI scans (PI-RADS ≥3) of men not diagnosed with PC in round 1 were re-read and classified according to Prostate Cancer Radiological Estimation of Change in Sequential Evaluation (PRECISE) by two radiologists. Interval PCs (detected outside the program before invitation to round 2) were identified by linking to the Regional PC Registry. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Tabulation of overall detection of PC was done. RESULTS AND LIMITATIONS: Between October 2017 and June 2020, 474 men with round 1 elevated PSA and MRI underwent a second screening. Of those, 19% had nonelevated PSA in round 2 and were not examined further. Of the remaining 376 men, 89% had negative MRI. Targeted biopsies yielded 14 PCs: nine grade group (GG) 1 and five GG 2-3. In men with PI-RADS ≥3 and PC diagnosed in round 2, only two (GG 1) progressed according to the PRECISE criteria and the remainder were stable. Ten interval PCs were diagnosed: seven GG 1, one GG 2, and two GG 5. The two GG 5 PCs were PI-RADS 4 and 5 with negative round 1 biopsy. CONCLUSIONS: A 2-yr interval seems to be safe in men with negative MRI, while men with PI-RADS 4 and 5 lesions with negative biopsies should have a closer follow-up. PATIENT SUMMARY: In prostate cancer screening, a 2-yr follow-up seems to be safe if magnetic resonance imaging did not show highly suspicious findings.