Men who undergo multiparametric magnetic resonance imaging (mpMRI) for suspected prostate cancer (PCa) and have negative findings are highly unlikely to have clinically significant PCa found on subsequent systematic prostate biopsy, according to a recent study.
Researchers at the Yale School of Medicine in New Haven, Connecticut, led by Preston C. Sprenkle, MD, found that men with no suspicious findings on prostate mpMRI had an approximately 3% chance of having clinically significant PCa—defined as Gleason grade 7 or higher—detected on systematic transrectal ultrasound (TRUS)-guided biopsy.
“Our results suggest that avoidance of systematic biopsy in patients with negative imaging results may be feasible,” the investigators concluded in a paper published online ahead of print in Urology.
The study included 100 men who underwent mpMRI followed TRUS-guided systematic prostate biopsy. Overall, 27 patients (27%) had PCa detected, including 10 (26.3%) of biopsy naïve men, 4 (12.1%) of 33 men who had a prior negative biopsy, and 13 (44.8%) of those previously on active surveillance. Gleason grade 7 or higher cancer was detected in 3 patients (3%) overall. The negative predictive value of a negative mpMRI was 73% for all PCa and 97% for Gleason grade 7 or higher cancer.
“While a negative MRI has been shown in this and other studies to have a high negative predictive value that may preclude the need for prostate biopsy, institutional experience is key to determining the risk of missing disease,” Dr Sprenkle told Renal & Urology News. “Urologists and radiologists should validate within their center if they have a similar low rate of positive biopsies in patients with a negative MRI.”
For example, he noted, some large academic centers, such as the University of California at Los Angeles, use the same biopsy technique as he and his colleagues do, with excellent radiologists and many years of experience, that have much higher rates of cancer detection in patients with a negative MRI.
The investigators acknowledged some study limitations, including the relatively small sample size of the overall cohort. In addition, they noted that their institution is a tertiary care referral center, so their patient population may differ from that of general practice patients.