A Canadian Phase III randomised trial findings suggest that prostate MRI screening is superior to serum prostate-specific antigen (PSA) for prostate cancer screening. However, the study was terminated due to the COVID-19 pandemic and could not reach statistical power. This research was published in the journal BMJ open.
The PSA test is routinely used for prostate cancer screening. Studies have shown that prostate MRI can improve the predictive value of PSA as compared to PSA alone. However, no studies have compared both these screening methods for their efficacy in detecting prostate cancer in men.
Nam and colleagues have conducted an open-label, randomised, controlled trial comparing PSA vs magnetic MRI for prostate cancer screening. The study enrolled 525 patients (50 years or older) with no history of PSA screening for ≥3 years or prostate biopsy. These participants were randomised to undergo either PSA screening (n=266) or MRI (n=248). Adenocarcinoma on prostate biopsy, prostate biopsy rates and clinically significant prostate cancer were the primary and secondary outcomes.
The study was terminated before completion due to the COVID-19 pandemic. The available data showed that 48 patients in the PSA arm had abnormal PSA, and 58% agreed to undergo a biopsy. Parallelly, 25 patients had a PIRADS score of 4 or more in the MRI, and 96% of these agreed to prostate biopsy. The cancer detection rate was higher in the MRI arm (63%) vs the PSA arm (29%), with a significantly higher cancer detection (73% vs 50%) with MRI than in PSA. Further, the relative risk for detecting cancer was 1.89 and 2.77 in MRI and PSA, respectively. Finally, the relative risk for MRI vs PSA to recommend biopsy was 0.52.
Taken together, the findings indicate the efficacy of MRI as screening method for prostate cancer.