According to a new University College of London-led computer modelling study, nearly one in six deaths from prostate cancer
could be prevented if targeted screening
was introduced for men at a higher genetic risk of the disease.
is the most common form of cancer
with around 1.3 million new cases diagnosed globally each year and more than 400,000 men
a year dying as a result of the disease. However, unlike breast and cervical cancer there is currently no national screening
programme for this disease in most countries.
Typically, a blood test that detects raised levels of the prostate
-specific antigen (PSA) can be used to screen for prostate cancer.
However, this test is not a reliable indicator as it does not accurately distinguish between dangerous cancers
from harmless ones,leading to both unnecessary operations and missed cancers
that are harmful.
The new study, published in PLOS Medicine
, modelled the harms and benefits of introducing four-yearly PSA screening for all men
aged 55 to 69 versus more targeted checks for those at higher risk of the disease.
The medical researchers concluded that the best approach would be to screen men
at a slightly higher genetic risk, nearly half of men
in that age group as this would have the biggest health benefit, preventing deaths from prostate cancer
while minimising unnecessary treatments for harmless tumours. This is because men
with a higher genetic risk are more likely to benefit and less likely to be harmed by undertaking screening.
is a leading cause of
in the UK, but screening is not performed because the harm of overdiagnosis is thought to outweigh the benefits. Our study shows that targeted screening
can reduce unnecessary diagnoses while helping to prevent people dying from the disease by enabling earlier detection." commented Professor Dr Nora Pashayan (UCL Applied Health Research), senior author of the study, during a phone interview with Thailand Medical
The researchers created a hypothetical cohort of 4.5 million men
, representing the number of men
aged 55 to 69 in England, and simulated the outcomes of introducing screening
into this population. Outcomes including prostate cancer
deaths averted, unnecessary diagnoses and screening
costs were compared for no screening
, universal age-based screening
using a range of thresholds of genetic risk.
The best optimal scenario, the researchers concluded, would be to screen men
with a 4-7% risk of getting prostate cancer
over the next 10 years,that is, between roughly half and a quarter of all men
aged 55 to 69.
Medical screening all men
in that age group would result in the most deaths averted (20%) but, along with the extra cost, would also lead to a large number of unnecessary diagnoses, with nearly one in three cancers
detected by screening being harmless.
It was showed that screening at a threshold of 4% would prevent 15% of deaths from prostate cancer
, nearly one in six deaths while delivering the greatest gains in terms of quality adjusted life years, meaning more years of good health across the population. This would also reduce the number of unnecessary diagnoses of harmless cancers
by about one third compared with screening all men
aged 55 to 69.
Medically screening men
with a 4-7% risk would also be much more cost effective than screening
aged 55 to 69, saving between a fifth (for the 4% risk threshold) to nearly half of the cost (7% risk threshold), while maintaining the benefits of screening
With the scenarios simulated, men
aged 55 to 69 would have four-yearly checks once they had reached the risk threshold. This would mean a widening proportion of men
having checks the older they got, as older men
are at greater risk of the disease.
New pioneering UCL-led research has already led to a change in the way prostate cancer
is diagnosed. As of last December, MRI is now recommended as the first test for men
suspected of having the cancer
, after two clinical trials conducted with University College London Hospitals (UCLH) trust found MRI scans could markedly and safely reduce the numbers of men
needing an invasive biopsy.
"I feel we now have the tools that help us identify men
with clinically important disease applying these tools to the right patient has to be the future. That is why this work is so important in helping us know who and when to screen
." said Professor Mark Emberton (UCL Medical Sciences).
The researchers said targeted screening
based on genetic risk would require an evolution of screening
services. They noted that inviting people for screening
at different ages may affect screening
delivery and that the broader impact of screening
using genetic risk required further research.
Reference : Tom Callender, Mark Emberton, Steve Morris, Ros Eeles, Zsofia Kote-Jarai, Paul DP Pharoah, Nora Pashayan, 'Polygenic Risk-Tailored Screening for Prostate Cancer: A Benefit-Harm and Cost- Effectiveness Modelling Study' PLOS Medicine (2019). DOI: 10.1371/journal.pmed.1002998