Short, noncontrast MRI, a potential screening tool for prostate cancer

The major outcome assessed was the proportion of men with positive MRI or ultrasonography (defined as a score of 3-5 or 4-5) or PSA test (defined as PSA ≥3 μg/L) results. They also assessed the number of clinically significant and clinically insignificant cancers detected if each test was used exclusively.

Key findings of the study were:

• When using the 3-to-5 score threshold, researchers noted that the proportion of men with positive results appeared higher with MRI (17.7%) and ultrasonography (23.7%) than with PSA testing (9.9%).

• While using sing the 4-to-5 score threshold, they found that the proportion with positive MRI results was similar to the proportion with positive PSA test results (43 [10.6%]), as was the proportion with positive ultrasonography results (52 [12.8%]).

• They noted that the PSA testing detected 7 of the clinically significant cancers, whereas an MRI detected 11 (4-5 threshold) to 14 (3-5threshold), and ultrasonography detected four (4-5threshold) to nine (3-5threshold).

• Of the 20 clinically insignificant prostate cancers detected on biopsy, they noted that the PSA testing detected 6, MRI detected 5(4-5threshold) to 7 (3-5threshold), and ultrasonography detected 7 (4-5threshold) to 13 (3-5threshold).

The authors concluded, " In this cohort study, when screening the general population for prostate cancer, MRI using a score of 4 or 5 to define a positive test result compared with PSA alone at 3 ng/mL or higher was associated with more men diagnosed with clinically significant cancer, without an increase in the number of men advised to undergo biopsy or overdiagnosed with clinically insignificant cancer. There was no evidence that ultrasonography would have better performance compared with PSA testing alone."

For further information:

https://jamanetwork.com/journals/jamaoncology/fullarticle/2776224