A Comparison of Magnetic Resonance Imaging Assessment and Biopsy Outcomes with and Without Central Review in Two Swedish Regional Organized Prostate Cancer Testing Programs.

BACKGROUND AND OBJECTIVE

The European Council advises evaluating the feasibility of organized prostate cancer testing (OPT) programs, but it is unclear whether results from screening trials can be replicated in population-based testing. The aim of this study is to compare magnetic resonance imaging (MRI) assessments and biopsy outcomes with and without a central review in two Swedish OPT programs.

METHODS

Two regional population-based OPT programs invited 65 000 men (2020-2022). MRI scans were read locally, and biopsies followed a strict MRI-based and prostate-specific antigen (PSA) density-based protocol. A blinded central review was done by two radiologists with 8 and 9 yr of experience. Reader agreement was assessed with percentages and kappa scores. Positive predictive values (PPVs) for detecting grade group (GG) 2-5 prostate cancer were calculated with 95% confidence intervals (CIs).

KEY FINDINGS AND LIMITATIONS

MRI scans for 416 men (median age 52 yr) with PSA ≥3 ng/ml were evaluated. In Skåne, 27% of scans were primarily assigned Prostate Imaging Reporting and Data System (PI-RADS) scores ≥4, compared with 10% in Västra Götaland. At the primary reading, 76 men had PI-RADS ≥4, yielding 43 GG 2-5 prostate cancer cases: PPV 0.57 (95% CI 0.45-0.67). At the central review, 65 men had PI-RADS ≥4. Out of 61 men biopsied, 50 had GG 2-5 prostate cancer: PPV 0.82 (95% CI 0.71-0.90,  < 0.001 for PPV difference). The central review radiologists' kappa score was 0.83. No additional biopsies were taken based on the central review findings.

CONCLUSIONS AND CLINICAL IMPLICATIONS

In population-based screening with local MRI reading, MRI assignment may vary substantially. Centralized reading could reduce these differences and increase the biopsy PPV for GG ≥2 cancer.

PATIENT SUMMARY

In this report, we reviewed local magnetic resonance imaging (MRI) reading in population-based screening. We found that MRI assignment varied between centers. We conclude that centralized reading could reduce differences and improve biopsy outcomes.