A twist on magnetic resonance imaging that does not require gadolinium contrast appears to be as effective as standard imaging at detecting prostate cancers, according to a new study in JAMA.
Experts said the findings, from the ongoing PRIME trial, should lead to the inclusion of so-called biparametric MRI in screening guidelines for prostate cancer in the near future. “With approximately four million
prostate MRIs performed globally annually, adopting biparametric MRI could substantially increase scanner throughput and reduce costs worldwide,” the researchers reported.
“The results from the PRIME trial, showing that a faster, cheaper type of prostate MRI is just as good as the current standard MRI at detecting prostate cancer, are a hugely important step in the right direction for making MRIs more efficient,” Matthew Hobbs, PhD, director of Research at Prostate Cancer UK, a research charity which helped fund the study, said in a statement.
Veeru Kasivisvanathan, MD, PhD
Veeru Kasivisvanathan, MD, PhD, of University College London, London, England, and the lead researcher of the PRIME trial, said he expects guidelines will soon begin favoring biparametric MRIs given the clear advantages of the procedure.
“You avoid injection, avoid gadolinium, have a shorter scan, there is no risk of allergic reactions or rare side effects, such as systemic nephrogenic fibrosis,” Kasivisvanathan said.
Kasivisvanathan and his colleagues from 22 hospitals in 12 countries across the world recruited 555 patients aged 59-70 years to see whether a streamlined two-part biparametric MRI could detect cancer at the same rate as a full three-part multiparametric MRI, currently the standard of care in the UK and the US. The three-part scan includes a stage during which a gadolinium dye is injected into the patient based on the theory that enhancing the image could improve image clarity and diagnosis.
All patients underwent the full three-part scan. Radiologists then assessed the two-part scan without dye and separately assessed the three-part scan with dye for every patient. A prostate biopsy was performed when required to confirm the diagnosis.
The researchers found clinically significant prostate cancer in 29% of men using the two-part scan, the same percentage as the longer three-part test.
The briefer MRI found “clinically insignificant” cancers in 9.2% of men in the study compared with 9.6% of men scanned with multiparametric MRI — a statistically insignificant difference, according to the researchers. The sensitivity, specificity, and positive and negative predictive values for the two imaging modalities did not differ meaningfully, they added.
“The PRIME study demonstrates that a shorter and less resource-intensive biparametric MRI detects as much clinically significant cancer as the full multiparametric MRI, without increasing the diagnosis of clinically insignificant cancer,” the researchers reported. “Despite earlier concerns that lack of contrast information would lead to more biopsy recommendations, this study found no evidence of this, with biopsy rates being very similar” for each method.
‘A Very Strong Case’
Todd Morgan, MD, chief of urologic oncology at the University of Michigan, in Ann Arbor, Michigan, said the study “makes a very strong case for moving toward biparametric MRI at centers where high-quality MRI is performed.”
Shifting to biparametric MRI leads to greater patient comfort and convenience — no intravenous, shorter scan times, and improved access to imaging because the tests take less time to perform — helps facilities by freeing up slots on the schedule for more scans, said Morgan, who co-authored an editorial in JAMA about the new study.
Benjamin Pockros, MD, MBA, a fourth-year urology resident at the University of Michigan who championed a transition to biparametric MRI at his institution, said he suspects insurers will not create hurdles to adopting the test, which tends to be significantly cheaper than conventional MRI.
In a 2024 study, Pockros and his colleagues found the price for MRIs for patients on commercial insurance was $2276 for multiparametric MRI and $1591 for a biparametric test. Gadolinium by itself costs over $1000, he added.
In Britain’s National Health Service, a three-phase MRI scan costs £273 on average, about 50% more than the two-phase scan, Kasivisvanathan noted. “In countries like the US, where healthcare costs tend to be much higher, the savings are likely to be even greater,” he said.
More than 95% of MRIs in the US and UK are multiparametric, added Pockros, who said he expects the balance to change after this study.
The sources in this story reported no relevant financial conflicts of interest.
Funding was received from John Black Charitable Foundation, Prostate Cancer UK, the European Association of Urology Research Foundation, and the Wolfgang Dieckmann Foundation.
Howard Wolinsky is a Chicago-based freelancer.