Two-thirds of men with a positive screening MRI for prostate cancer had PSA levels below 3 ng/mL and 91 percent of these men had clinically significant prostate cancer, according to newly published research.
Emerging research findings emphasize the role of magnetic resonance imaging (MRI) in detecting clinically significant prostate cancer (csPCa) in men with normal prostate-specific antigen (PSA) levels.
For the study, recently published in BMJ Oncology, researchers assessed data from 303 men who had a screening non-contrast MRI (sMRI) and PSA testing. Positive findings for prostate cancer were defined as a positive sMRI or PSA density > 0.12 ng/mL, according to the study. The study authors noted that PSA density was obtained by measuring prostate volume on sMRI.
Forty-eight men had positive sMRI findings for prostate cancer with 32 of the men having a PSA level below 3 ng/mL. The researchers also pointed out that 60 percent (15 of 25 men) of those with a positive MRI and csPCa had a PSA below 3 ng/mL. Subsequent biopsy results in these patients included 13 Gleason 3+4 cancers, according to the study.
“The finding in this report … that 2 in 3 men with a positive screening MRI have a PSA < 3 ng/mL is a sobering one because MRI lesions are positively associated with clinically significant cancer. Using MRI to detect cancers can allow pick up of significant lesions before the PSA has begun to rise … (and offers) an opportunity for early detection,” wrote lead study author Caroline M. Moore, M.D., a professor of urology in the Department of Targeted Intervention within the Division of Surgery and Interventional Science at University College London in the United Kingdom, and colleagues.
Out of the 255 study participants who had a negative sMRI, the researchers found that 16 men had a greater PSA density than 0.12 ng/mL (a measurement determined by assessing prostate volume on sMRI). The study authors found that four of these men had csPCa and one man had clinically insignificant prostate cancer.
“In clinical practice, we recognize that the PSA test has limitations in the identification of men at risk for prostate cancer. MRI may allow us an alternative way to assess prostate cancer risk in men in the community,” added Moore and colleagues.
While acknowledging lower numbers of Black (13 participants, 5 percent of cohort) and Asian study participants (10 participants, 3 percent of cohort), the study authors said logistic regression analysis demonstrated significantly higher PSA density in Black and Asian men. The researchers also noted that none of the 13 Black study participants had positive MRI findings for prostate cancer.
(Editor’s note: For additional articles on prostate cancer imaging, see https://www.diagnosticimaging.com/clinical/prostate-cancer .)