MRI-guided biopsy decisions halve the rate of clinically insignificant prostate cancer diagnoses

Prostate MRI screening exams could reduce instances of over diagnosis and treatment in patients with clinically insignificant cancer, according to new work published this week in the New England Journal of Medicine. 

Results from the research suggest that omitting biopsy in patients without high-grade lesions on MRI cuts rates of clinically insignificant cancer diagnoses by more than half. The benefits versus risks of MRI screening for prostate cancer have been heavily debated in recent years, but researchers involved in this latest paper suggest that their work may be the evidence needed to tip the scales in favor of imaging utilization. 

Lead author Jonas Hugosson, MD, PhD, a professor of urology at the University of Gothenburg in Sweden, suggested that his team's results could be “the last piece of the puzzle to have real evidence that the benefits of prostate screening exceed the harms on a population level.” 

“This paper is the message to healthcare authorities around the world to look over recommendations for men,” he wrote in an editorial alongside the study. 

Researchers included around 13,000 men in the analysis. If they had a PSA of 3 ng per milliliter or higher, they were sent for an MRI. Participants were then randomly assigned to two cohorts—a systematic biopsy group and a targeted alternative that underwent biopsy only if they had suspicious lesions on imaging. 

After a median follow-up of about four years, prostate cancer was detected in 2.8% of the MRI-targeted biopsy group and 4.5% of the systematic biopsy group. The risk of detecting clinically insignificant cancer in the targeted biopsy group was 0.43, compared to 0.84 for clinically significant cancer. Significantly fewer advanced cancers were identified in the targeted group as well, the authors noted. 

“We reduce biopsy frequency by about 60%. If you look at the overdiagnosis rate, we reduce that by approximately 57%,” Hugosson wrote. “That is very valuable.” 

The authors acknowledged that there are still accessibility barriers that stand in the way of some patients undergoing a prostate MRI screening, though they maintained that their results offer further evidence of its safety and efficacy where the exam is feasible.