Targeted screening for prostate cancer ‘could prevent up to one in six deaths'
A screening programme targeted at men who are genetically predisposed to prostate cancer, and involving a blood test and MRI scan before an invasive biopsy, could prevent one in six prostate cancer deaths, a new study has suggested.
It could also significantly reduce over-diagnosis, researchers say.
Prostate cancer is the most common form of cancer in men, with around 130 new cases diagnosed in the UK every day and more than 10,000 men a year dying as a result of the disease.
However, there is currently no national screening programme for the disease in the UK.
Men suspected of having the disease have a blood test that detects raised levels of the prostate-specific antigen (PSA).
The National Institute of Clinical Excellence (NICE) guidelines also advise that all men with a positive PSA result have an MRI scan prior to biopsy.
UCL researchers say recently discovered genetic markers that predict prostate cancer risk could also complement a PSA test and MRI scan.
A polygenic test, which is not yet widely available, can identify those with high-risk prostate cancer genes and help predict when an individual is likely to start to benefit from screening.
Co-author, Professor Mark Emberton, UCL Dean of the Faculty of Medical Sciences, said: “Our study shows that screening for prostate cancer – which could save between 16% and 20% of prostate cancer deaths – might be possible with targeted screening using genetic risk and MRI as part of the diagnostic pathway.
“This paves the way for further clinical trials to study the real-world implementation of such a screening programme.”
Lead author Dr Tom Callender, UCL Division of Medicine, said: “Prostate cancer is a leading cause of death from cancer amongst men, but there is no screening programme because the harms of screening are considered to outweigh the benefits.
“However, those at higher genetic risk are more likely to benefit from screening and less likely to be harmed.
“For this benefit-harm and cost-effectiveness analysis, we asked how effective a four-yearly PSA screening for all men aged 55 to 69 would be versus more targeted checks for those at higher risk of the disease based on their age and genetic profile.
“We also asked what the impact would be of those with a positive PSA blood test having an MRI scan before a biopsy, in the context of a prostate cancer screening programme.”
In the modelling study researchers created a hypothetical cohort of 4.5 million men, representing the number of men aged 55 to 69 in England.
They simulated the health outcomes of introducing either age-based and risk-tailored screening programmes into this population.
The age-based diagnostic pathway modelled a screening programme in which all men aged between 55 and 69 would receive a PSA test every four years.
If the test was positive, this would be followed by MRI and biopsy if required.
The risk-tailored pathway modelled a screening programme in which men would get a PSA test (followed by MRI and biopsy if required) if and when their risk – determined by their age and polygenic risk score (genetic profile) – reached a certain threshold.
Health outcomes along with screening costs were compared for no screening, universal age-based screening and more targeted risk-based screening using a range of risk thresholds.
Researchers found the scenario which generated the most benefits would be to screen men with a 3.5% risk of getting prostate cancer over the next 10 years – roughly half of all men aged 55 to 69.
They suggest such a programme could prevent up to 16% of prostate cancer deaths – nearly one in six deaths – and reduce overdiagnosis by 27%.
Screening men at this threshold (3.5%) would also be more cost-effective than screening all men aged 55 to 69, the study indicates.
Screening all men in that age group would result in the most prostate cancer deaths prevented (20%).
However, targeted risk-based screening prevents a similar number of deaths whilst reducing the number of over-diagnosed cancers and the number of biopsies needed by approximately one third, researchers say.
This study, published in JAMA Network Open, was carried out with researchers from the University of Cambridge.