A targeted, risk-based breast screening programme could help reduce overtreatment and be run at an affordable cost to the NHS, a new study led by researchers at University College London has found.
In a new economic evaluation and simulation modelling study – published in JAMA Oncology – researchers concluded that a screening initiative that targeting screening based on women’s individual level of risk could improve the quality of life gained following screening, reduce overdiagnosis (the diagnosis of non-invasive tumours that would not have caused harm in women’s lifetimes), while reducing costs for the NHS.
The NHS Breast Screening Programme invites women aged 50-70 for screening every three years to help spot breast cancers sooner. Advances in recent years have shown that the risk of developing the disease varies significantly among women, due to genetic, lifestyle and reproductive factors – and there is now real hope that a ‘risk-stratified’ programme to target screening to those that need it the most could help to prevent more deaths from breast cancer and help women at low risk avoid screening they may not need.
The study simulated three cohorts of women who were aged 50 and free of cancer, which were followed up over 35 years. Each cohort consisted of 364,500 women – the 2009 population of women aged 50 in England and Wales. The first group received no screening, the second received a mammography at age 50, and for every three years thereafter – simulating the Breast Screening Programme – while for the third cohort, a risk estimation was carried out and only those with a risk score greater than the threshold (low) risk, were offered screening every three years from 50 until aged 69.
The modelling study suggested that if screening was not offered to women at the lowest 30% of the risk distribution, there could be 27% fewer overdiagnoses, and the NHS would save £20,000 – but 3% more women would die from breast cancer. Increasing the risk threshold to target screening to the 30% of women at the highest risk, saw 71% fewer overdiagnoses, and savings for the NHS of £538,000 – but 10% more women died from breast cancer as a result.
Baroness Delyth Morgan, Chief Executive at Breast Cancer Now, said:
While we remain hopeful that ‘risk-stratified screening’ will offer another significant step forward in the early detection and prevention of breast cancer, it’s extremely concerning that this particular model would see more women die from their disease as a result.
Major advances in our knowledge about the genetic and lifestyle causes of the disease now mean that we are closer than ever to being able to offer women screening based on their individual risk, rather than just their age. By tailoring screening in this way, we could ensure that the women most likely to benefit from screening are offered it more regularly, while those at very low risk may be able to attend less frequently.
The Breast Screening Programme is absolutely critical to early diagnosis in this country, preventing 1,300 deaths from breast cancer each year. Using an even more personalised approach could help detect more cases earlier, while enabling those at particularly low risk to avoid unnecessary screening – but to stop more women dying from breast cancer, we first need to develop accurate risk prediction tools and find ways to support women to reduce their risk of the disease.
In the meantime, we’d encourage all women to attend screening when invited and to check their breasts regularly, reporting any unusual changes to their GP.
The study was funded by Cancer Research UK and led by the UCL Department for Applied Health Research, with support from the University of Cambridge.