Ultrasound + MRI Improves High-Grade Prostate Cancer Detection
Well demarcated hypoechoic areas in suspicious regions on MRI identify men more likely to have Gleason 7 or higher prostate cancer found on biopsy.
Ultrasound characteristics of prostate regions that appear suspicious on magnetic resonance imaging (MRI) may help predict the likelihood of finding clinically significant prostate cancer (PCa) on biopsy, investigators reported in BJU International.
In a prospective study of 672 men who undergoing MRI-ultrasound (US) fusion targeted prostate biopsy, Samir Taneja, MD, of New York University Langone Health, and colleagues found that patients with well demarcated hypoechoic areas at an MRI region of interest (ROI) at the time of biopsy had an increased risk of high-grade PCa (Gleason score 7 or higher) detection, independent of MRI suspicion score.
A single radiologist identified and scored the MRI ROI for all study enrollees. Investigators prospectively evaluated for the presence of a hypoechoic region at the ROI and graded the site using 3 US categories—none, poorly demarcated, or well demarcated, represented as US grades 0, 1, and 2, respectively.
The overall rate of PCa detection was 61.2%. The rate of detection of Gleason score 7 or higher cancer was 39.6%. The cancer detection rate for US grade 0, 1, and 2 were 46.2%, 58.6%, and 76%, respectively, for any cancer, and 18.7%, 35.2%, and 61.1% for Gleason score 7 or higher cancer, respectively. For MRF-TB only, the cancer detection rates of Gleason 7 or higher cancer for US grade 0, 1, and 2 were 12.8%, 25.7%, and 52%, respectively.
With regard to study limitations, the authors noted that the ultrasound observations were made by a single surgeon, so the results may not be widely generalizable until further validated. In addition, the investigators did not incorporate MRI or transrectal ultrasound (TRUS) lesion size into their analysis.
“Overall, I think this is a good study, and [US grading] may provide another technique that can guide biopsies which may aid in detecting clinically significant prostate cancer,” said Jason Palopoli, MD, a medical oncologist at Christiana Care Health System in Newark, Delaware. “I think what is most intriguing is that ultrasound grading may help to delineate low-suspicion MRIs and the need for a biopsy. Ideally, the technique employed by urologists will have the highest detection rate of clinically significant prostate cancer and the lowest detection rate of clinically insignificant prostate cancer.”
Conventional systematic TRUS-guided biopsy can results in false-negative findings and possibly lead to PCa undergrading, he noted.
Katarzyna Macura, MD, PhD, Professor of Radiology and Radiological Science at Johns Hopkins University School of Medicine in Baltimore and a member of the PI-RADS Committee at the American College of Radiology, said the findings from the current study, if validated, may help lead to better treatment plans and potentially better outcomes. “The results are very good,” Dr Macura said. “It [US grading] can provide a clinical benefit. By looking at the region of interest, urologists can get the data they need.”
Adopting this approach may provide clinicians with an added layer of confidence. “The MRI is like a finger pointing. This [use of US] now allows them to focus their attention better,” Dr Macura said.
Press B, Rosenkrantz AB, Huang R, Taneja SS. The ultrasound characteristics of MRI suspicious regions predict the likelihood of clinically significant cancer on MRI-ultrasound fusion targeted biopsy. BJU Int. 2018. Published online ahead of print.