Study: 'All Men with PSAs Between 3 and 20 ng/mL Should Undergo MRI Before Biopsy'

Can pre-biopsy magnetic resonance imaging (MRI) have an impact in reducing unnecessary biopsies?

In a new retrospective study, recently published in JAMA Network Open, researchers in Sweden compared a 2.4-year time period when pre-biopsy MRI use was low (from November 2, 2015 to February 28, 2018) and a subsequent 2.4-year time period (from March 1, 2018 to July 31, 2020) that showed a gradual increase of pre-biopsy MRI use in patients with suspected prostate cancer. The cohort was comprised of 23,802 men (mean age of 60.8) who had prostate-specific antigen (PSA) testing, according to the study. The researchers pointed out that pre-biopsy MRI has been recommended in national prostate cancer guidelines in Sweden since 2018.

The researchers found the use of pre-biopsy MRI was associated with a 7 percent rate of negative biopsies in comparison to 28 percent prior to adoption of pre-biopsy MRI. Diagnosis of Gleason score 6 cancers declined by 18 percent (6 percent vs. 24 percent) during the pre-biopsy MRI period of the study, according to the study authors.

The study authors also found that use of pre-biopsy MRI also resulted in a 37 percent increase in the proportion of diagnosed Gleason score 7 to 10 cancers (86 percent vs. 49 percent) in comparison to the period prior to wider use of pre-biopsy MRI.

“In this population-based cohort study, the introduction of MRI was associated with a decrease in prostate biopsies, a decrease in negative biopsies, and a decrease in the detection of Gleason score 6 cancer, whereas the detection of Gleason score 7 or higher cancer increased,” wrote lead study author David Robinson, Ph.D., who is affiliated with the Department of Urology at Highland Hospital in Eksjo, Sweden, and colleagues.

For men diagnosed with prostate cancer who had an initial PSA of 3 < 20 ng/mL, the researchers added that a sensitivity analysis revealed a 22 percent reduction in Gleason score 6 cancers detected via pre-biopsy MRI (16 percent vs. 38 percent). Multivariable regression modelling revealed that higher use of pre-biopsy MRI led to fewer biopsies and a decreased risk of negative biopsies (odd ratio of 0.70) in comparison to the period prior to wider use of pre-biopsy MRI.

While emphasizing the need for larger cohort studies to validate these findings and explore the impact of pre-biopsy MRI on pertinent subgroup populations, Robinson and colleagues said the current findings “support that all men with PSAs between 3 and 20 ng/mL should undergo MRI before biopsy.”

In regard to study limitations, the researchers noted that the peak of the COVID-19 pandemic occurred during the study period with a corresponding decrease in PSA testing. They also noted a lack of clear separation between targeted and systematic biopsies reported in Sweden’s National Prostate Cancer Register (NPCR).