Faster and cheaper MRI proves effective in detecting prostate cancer

A quicker, cheaper MRI scan was just as accurate at diagnosing prostate cancer as the current 30-40 minute scan and should be rolled out to make MRI scans more accessible to men who need one, according to clinical trial results led by UCL, UCLH and the University of Birmingham.

The PRIME trial, funded by the John Black Charitable Foundation and Prostate Cancer UK, and published in JAMA, confirms that a two-part MRI scan is just as effective at diagnosing prostate cancer, whilst cutting scan time to just 15-20 minutes and reducing the need for a doctor to be present.

The investigators say the results are likely to lead to changes in clinical practice, making MRI accessible to more men in the UK and beyond.

Prostate cancer is the most common cancer in men, with around 56,000 diagnoses and 12,000 deaths each year in the UK. The introduction of MRI scans over the last decade, following work by UCL researchers, has been the biggest change in how prostate cancer is diagnosed for the past 30 years.

Abnormalities seen on the MRI scan allow targeted tissue biopsies to be taken that can improve cancer detection. A normal MRI result, which occurs in around a third of patients, is reassuring and allows men to avoid an unnecessary biopsy.

Despite the clear benefits of the MRI scan, in many healthcare settings around the world, men who need a scan still do not get one. For example, previous research has estimated that 35% of US prostate cancer patients received an MRI in 2022. In England and Wales, only 62% of men who needed a prostate MRI received one in 2019 (the most recent year for when data is available).

Associate Professor Veeru Kasivisvanathan, lead researcher and Chief Investigator on the trial from UCL Surgery & Interventional Science and UCLH, said: “Currently around four million MRI scans are needed each year globally to diagnose prostate cancer. This demand is set to rise rapidly with a predicted surge in prostate cancer cases over the next 20 years.   

“Time, cost and staff availability are all limiting factors in how many scans can be offered, which makes the results of the PRIME trial particularly important. If we can do the scan in up to half the time, with fewer staff and at lower cost, that will make a huge difference in allowing every man who needs a scan to be able to get one in a timely fashion.”

In the study, cancer specialists from 22 hospitals in 12 countries across the world recruited 555 patients aged 59-70 to see whether a streamlined two-part ‘biparametric’ MRI could detect cancer at the same rate as a full three-part ‘multiparametric’ MRI, which is currently standard of care in the UK and includes a third stage where a dye is injected into the patient.

All patients underwent the full three-part scan. Radiologists then assessed the two-part scan without the dye, and separately assessed the three-part scan with the dye, for every patient. A prostate biopsy was done when required to confirm whether or not the diagnosis was correct.

Researchers from UCL and UCLH confirmed that the two-part scan was just as effective at diagnosing prostate cancer. In total, 29% of the patients had important prostate cancer diagnosed by the shorter two-part scan, the same percentage as the longer three-part scan.

Associate Professor Francesco Giganti, a lead radiologist on the trial from UCL Surgery & Interventional Science and UCLH, said: “The three-part multiparametric MRI scan has been a game-changer for the diagnosis of prostate cancer, sparing thousands of patients unnecessary biopsies and improving cancer detection.

“Currently we inject a dye into the patient that highlights the presence of cancer on the MRI scan, but this step requires time and the presence of a clinician, and can on rare occasion cause mild side effects.

“Being able to make accurate diagnoses without the contrast stage will reduce scan time meaning we can offer scans to more men using the same number of scanners and operators. However, it is vital that the scans are of optimal diagnostic quality and that they are interpreted by a radiologist with dedicated expertise in prostate MRI.”

As well as making the procedure more efficient in terms of time and personnel, a two-stage MRI would generate significant cost savings per scan. In the NHS currently, a three-phase MRI scan costs £273on average. At £145, a two-phase scan is 47% cheaper. In countries like the US where healthcare costs tend to be much higher, the savings are likely to be even greater.

Prostate Cancer UK’s TRANSFORM trial, the biggest prostate cancer screening trial for 20 years that will include MRI, is due to begin later this year. It will be jointly led by UCL researchers alongside collaborators from Imperial College London, The Institute of Cancer Research and Queen Mary University of London. The trial will find the best way to screen men for prostate cancer, achieving the evidence needed for the introduction of a national screening programme. The results of the PRIME trial are an important step towards realising this ambition.

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.

Another trial is already happening in the UK and the results of the two trials together should provide the complete evidence package we need to change practice across the country. We encourage NICE to prepare to review their guidelines as soon as that evidence base is complete, so that we can make MRI quicker, cheaper and less onerous for men.

Our funding for PRIME, alongside the John Black Charitable Foundation, also provided recommendations of a few simple ways for hospitals to improve scan quality. So, while we await a review by NICE, hospitals should use guidelines from UCL’s GLIMPSE trial, so that they are ready for the implementation of biparametric MRI if it’s recommended, and so that the men having MRI scans right now get the most accurate scan possible.”

Dr. Matthew Hobbs, Director of Research at Prostate Cancer UK

The PRIME study also received funding from the European Association of Urology Research Foundation and the Wolfgang Dieckmann Foundation.

Dr. Aqua Asif, co-first author of the study from UCL Surgery & Interventional Science, said: “These findings show that we can deliver faster, more accessible prostate MRI scans without compromising accuracy. That has the potential to transform care, allowing more men to get the scans they need, when they need them, and ultimately improving outcomes worldwide. It has been a privilege to contribute to PRIME at this stage of my career, and I am incredibly proud of what has been achieved through the dedication of our collaborators across so many centres. This trial would not have been possible without the support of our funders, our patients, and the commitment of the entire team.”

Dr. Alexander Ng, co-first author of the study from UCL Surgery & Interventional Science, said: “Since we introduced MRI into the prostate cancer pathway, it has been our missions to ensure that every man who requires an MRI can get one. PRIME is a major leap in this direction, allowing men to receive a shorter, cheaper and less invasive scan that is just as good as a longer, more expensive scan that requires an intravenous cannula with an injection. We continue to strive to improve the global equity in access to an accurate and timely prostate cancer diagnosis, to improve the prostate cancer paradigm for patients all around the world.”