Targeted biopsy with MRI associated with major reduction in prostate cancer overdiagnosis

A study recently published in the New England Journal of Medicine suggests that a systematic biopsy may not be necessary for all men with elevated prostate-specific antigen (PSA) levels.1

The study of 17,980 men who had prostate cancer screening showed the use of magnetic resonance imaging (MRI)-targeted biopsy reduced the risk of diagnosing Gleason 3+3 cancers in half in comparison to the use of systematic biopsy.

Overall, the investigators compared the use of systematic biopsy and multiparametric MRI-targeted biopsy in a reference group of 5994 participants to the use of MRI-targeted biopsy only in an experimental group of 11,986 participants. In the experimental group, the study authors reserved the use of MRI-targeted biopsy for men who had Prostate Imaging Reporting and Data System (PI-RADS) scores of 3 to 5.

Out of the 11,986 participants in the experimental group, 66 men (0.6%) were diagnosed with Gleason 3+3 scores (clinically insignificant cancer) whereas 72 men in the reference group of 5994 participants (1.2%) had Gleason 3+3 scores, according to the study.

“Since the frequent detection of small Gleason 3+3 cancers after PSA screening is regarded as a major contributor to the high incidence of potentially harmful overdiagnosis of prostate cancer, this finding is of importance,” wrote lead study author Jonas Hugosson, MD, PhD, who is affiliated with the Department of Urology at Sahlgrenska University Hospital in Gothenburg, Sweden, and colleagues. “This strategy also considerably reduced the percentage of biopsies in participants in the experimental group who had elevated PSA levels.”

The study authors also noted tumor size differences between the clinically insignificant cancers diagnosed in the experimental and reference groups.

“Gleason 3+3 cancers that were detected in the experimental group were in general larger than those detected in the reference group and may potentially have had clinical importance, especially in this relatively young age group (median age of 56) in which grade progression might occur with increasing age,” said Hugosson and colleagues.

While acknowledging 19% fewer cases of clinically significant cancers diagnosed in the experimental group, the researchers said the cancers detected in 10 participants with systematic biopsy alone “were mostly small and all had a Gleason score of 3+4 with a small amount of Gleason pattern 4 detected.” Four of these patients had radical treatment and the remaining six patients had active surveillance, according to Hugosson and colleagues.

Reference

1. Hugosson J, Månsson M, Wallström J, et al. Prostate Cancer Screening with PSA and MRI Followed by Targeted Biopsy Only. N Engl J Med. 2022;387(23):2126-2137. doi: 10.1056/NEJMoa2209454