Men who dread the prospect of multicore prostate biopsies can take heart in the news that multiparametric MRI with or without targeted biopsy was noninferior to transrectal ultrasound at detecting clinically significant cancers, results of a multicenter randomized trial indicate.
The rate of clinically significant cancers detected in men with clinical suspicion of prostate cancer who were randomly assigned to undergo MRI was 38%, compared with 26% (P = .005) for men assigned to standard transrectal ultrasound guided biopsy with 10 or 12 biopsy cores, reported Veeru Kasivisvanathan, MRCS, of University College London, and colleagues in the PRECISION trial (Prostate Evaluation for Clinically Important Disease: Sampling Using Image-guidance or Not?).
Significantly fewer men assigned to MRI-targeted biopsy were diagnosed with clinically insignificant cancers, suggesting that MRI could help to reduce the number of invasive biopsies and the associated pain, discomfort, and infection risks, the investigators stated in the New England Journal of Medicine.
“MRI, with or without targeted biopsy, led to fewer men undergoing biopsy, more clinically significant cancers being identified, less overdetection of clinically insignificant cancer, and fewer biopsy cores being obtained than did standard transrectal ultrasonography-guided biopsy,” they wrote.
Multiparametric MRI combines several different imaging modalities, including standard T1- and T2-weighted scans with dynamic contrast–enhanced and/or diffusion-weighted imaging to provide a wealth of information to aid in diagnosis. The technique has been shown in single-center studies to be similar or superior to ultrasound guided biopsy at detecting clinically significant cancers and minimizing detection of cancers that turn out to be clinically insignificant, the investigators said.
To add to the body of evidence, investigators from 25 centers in 11 countries randomized a total of 500 men with clinical suspicion of prostate cancer and no history of prostate biopsy to undergo either MRI plus targeted biopsy (not 10- or 12-core biopsy) if the scans indicated suspicion of malignancy, or standard transrectal ultrasound-guided biopsy with 10 or 12 core samples.
The investigators defined clinically significant cancer as the presence of a single biopsy core indicating disease of Gleason score 3 plus 4 (Gleason sum of 7), or greater.