Radiologist monitoring of prostate magnetic resonance imaging (MRI) exams could significantly reduce the use of dynamic contrast enhanced MRI (DCE MRI) with little impact on sensitivity for clinically significant prostate cancer (csPCa), according to new research.
For the retrospective study, recently published in European Radiology, researchers evaluated the use of radiologist on-table monitoring of T2-weighted and diffusion-weighted imaging (DWI) MRI to determine whether subsequent DCE MRI was necessary. The study authors compared this monitoring approach in 178 patients vs. unmonitored prostate MRI in 420 patients.
The researchers found that on-table monitoring of prostate MRI exams by radiologists prevented the use of gadolinium contrast in 135 of the 178 (75.8 percent) monitored patients.
Monitored prostate MRI exams offered a comparable sensitivity rate to unmonitored MRI exams (98.3 percent vs. 99.2 percent) and there was a comparable number of cases that required biopsy (52.2 percent vs. 49.5 percent), according to the study authors.
“On-table monitoring significantly reduced the need for gadolinium contrast without compromising diagnostic accuracy and biopsy rates,” wrote lead study author Tom Syer, M.D., who is affiliated with the Departments of Radiology at Addenbrookes Hospital and the University of Cambridge in Cambridge, United Kingdom, and colleagues.
The researchers estimated that the monitoring protocol could result in $5,190 in cost savings per 100 prostate MRI exams, adding up to $49,295 per year at their facility.
However, the study authors noted improved specificity with non-monitored prostate MRI (70.7 percent vs. 63.9 percent). Dynamic contrast-enhanced MRI was useful in 29 out of 43 cases (67.4 percent) with upgrading of initial PI-RADS 3 peripheral zone lesions to PI-RADS 4 categories for 13 of 27 patients, according to the researchers.
Three Key Takeaways
1. Reduction in gadolinium use. Radiologist on-table monitoring of prostate MRI significantly decreased the need for gadolinium-based contrast, preventing its use in 75.8 percent of monitored patients while maintaining comparable sensitivity for detecting clinically significant prostate cancer.
2. Comparable diagnostic accuracy. The sensitivity of monitored MRI exams (98.3 percent) was nearly identical to that of unmonitored exams (99.2 percent), and biopsy rates were similar (52.2 percent vs. 49.5 percent), suggesting that on-table monitoring does not compromise diagnostic effectiveness.
3. Cost savings and personalization. The monitoring protocol could lead to substantial cost savings (approximately $49,295 per year at the study facility) while enabling more personalized MRI protocolling, reducing contrast-related side effects and unnecessary biopsies in selected patients.
In order to reconcile the pros and cons of monitored and non-monitored approaches to prostate MRI, the study authors emphasized proactive protocolling and scheduling to identify patients who have a stronger need for DCE MRI.
“There are suggestions it may be beneficial to perform DCE routinely in patients with pelvic metalwork, lower PSA (prostate-specific antigen) values or individuals where the risk of missing significant disease outweighs the risk of false positives and unnecessary biopsies,” added Syer and colleagues. “Even if on-table monitoring would not increase scanning throughput, it allows for more (personalized) protocolling, reducing contrast-related side effects and costs.”
(Editor’s note: For related content, see “AI and bpMRI for csPCA Detection: What a New Meta-Analysis Reveals,” “Meta-Analysis Shows No Difference Between bpMRI and mpMRI in Ruling Out csPCa” and “Can Deep Learning Ultra-Fast bpMRI Have an Impact in Prostate Cancer Imaging?”)
Beyond the inherent limitations of a single-center retrospective study, the authors acknowledged the possibility of patient selection bias, noting a weekly session for prospective data collection in the on-table monitoring cohort in comparison to data collection throughout the week for the control group. They also conceded retrospective assignment of PI-QUAL v2 scores to a subset of the cohort as the PI-QUAL v2 system was published after commencement of the study.
