Enhanced breast cancer screening in the UK could detect an extra 3,500 cancers per year, Cambridge trial shows
Example images of healthy breasts showing fatty/least dense breast (left) and dense (right)
22 May 2025
Researchers in Cambridge are calling for additional scans to be added to breast screening for women with very dense breasts. This follows a large-scale trial, supported by the NIHR Cambridge BRC, which shows that extra scans could treble cancer detection for these women potentially saving up to 700 lives a year in the UK.
Around 10% of women have very dense breasts. Between the ages of 50 and 70, these women are up to four-times more likely to develop breast cancer compared to women with low breast density.
Over 2.2 million women receive breast screening in the UK each year. For women with very dense breasts, mammograms (breast X-rays), which are used for breast screening, can be less effective at detecting cancer. This is because denser breasts look whiter on mammograms, which makes it harder to spot small early-stage cancers which also appear white.
Breast density varies naturally between women and typically declines with age . ‘Dense breasts’ is a categorical term for breasts that contain more glandular and connective tissue and less fatty tissue. A woman won’t know if she has dense breasts unless she is told following a mammogram.
Published today (22nd May 2025) in The Lancet, a trial of over 9000 women across the UK who have dense breasts and had a negative (no cancer) mammogram result, found 85 cancers.
The trial, called BRAID, tested different scanning methods that could be used in addition to mammograms to detect cancers in dense breasts. Per 1000 women screened, two of the methods detected 17-19 cancers that were not seen in mammograms.
The two methods are known as CEM (contrast enhanced mammography) and AB-MRI (abbreviated magnetic resonance imaging). CEM is an X-ray scanning method, similar to a mammogram. AB-MRI is a faster version of an MRI scan.
The researchers that ran the trial recommend that adding either of these methods to existing breast screening could detect 3,500 more cancers per year in the UK. Estimates suggest that screening reduces mortality for about 20% of cancers detected, so this could mean an extra 700 lives saved each year.
BRAID also included a third scanning method, ABUS (automated whole breast ultrasound), which also detected cancers not seen in mammograms but was three times less effective than CEM and AB-MRI.
Each of the three methods was used to scan around 2000 women. Per 1000 women scanned, CEM detected 19 cancers, AB-MRI found 17 cancers, and ABUS found 4.
Mammograms already detect approximately 8 cancers per 1000 women with dense breasts. This means additional scans could more than treble breast cancer detection in this group of women.
BRAID is the first trial to directly compare supplemental imaging methods and to demonstrate their value for early cancer detection as part of widespread screening. The team hope their results will be used to enhance screening programmes in the UK and globally to diagnose more cancers early.
More work is needed to confirm whether additional scans will reduce the number of deaths as cancers detected through screening are not always life-threatening.
The trial was led from Cambridge. It recruited across 10 UK sites, including over 2000 women at Addenbrooke’s Hospital, Cambridge.
