A new test that can spot cervical cancer years before it happens could transform screening for four cancers, scientists say. A study found it was able to detect more than half of women whose screening results came back normal but went onto to develop signs of cancer in the next four years.
Experts believe the test — which can also pick up DNA markers for other cancers — could be used to predict breast, womb, cervical and ovarian cancer within years — all from the same swab.
A study found it was able to detect more than half of women whose screening results came back normal but went onto to develop signs of cancer in the next four years. Experts believe the test – which can also pick up DNA markers for other cancers – could be used to predict breast, womb, cervical and ovarian cancer within years – all from the same swab. Stock
It has the potential to save thousands of women from undergoing gruelling cancer treatments and painful biopsies by flagging those at most risk before cancer develops.
It would also spell the end of mammograms, traditionally used to screen women over-50 for breast cancer.
The new test looks at DNA methylation — an extra layer on top of DNA which tells cells what their specific function is.
By studying this using cervical swabs, scientists found changes to cells can be spotted well before they become cancerous.
Under current screening, women are tested for human papillomavirus (HPV) – the virus responsible for 99 per cent of cervical cancer cases.
The samples of those who test positive are then checked under the microscope for cell changes that could become cancerous.
How does the test work?
The new test looks at DNA methylation – an extra layer on top of DNA which tells cells what their specific function is.
By studying this using cervical swabs, scientists found changes to cells can be spotted well before they become cancerous.
Under current screening, women are tested for human papillomavirus (HPV) – the virus responsible for 99 per cent of cervical cancer cases.
The samples of those who test positive are then checked under the microscope for cell changes that could become cancerous.
Researchers looked at 1,254 cervical screening samples from women with cell changes ranging from lower to high risk, women with HPV but no cervical cell changes, and samples from women without any cervical cell changes who went on to develop high-risk cell changes within four years.
For those without cell changes but who had HPV, it detected 55 per cent of people who would have cell changes in the next four years.
It also performed better than currently available methods for detecting those with advanced cell changes who need treatment, according to the findings published in the journal Genome Medicine.
Scientists believe that by looking closely at DNA methylation, they can detect cancer and possibly predict the risk someone has of developing cancer in the future.
They are also confident cells taken during cervical screening have the potential to flag future breast, ovarian and womb cancers, in what they have called a ‘surrogate effect’.
Dr Chiara Herzog, of the University of Innsbruck, Austria, said other tests work by picking up cells shed by the cancer, meaning cancer has to be present.
But by studying a person’s DNA methylation — which can be altered by factors like age, pollution, weight — someone’s chances of getting cancer can be predicted.
‘The idea is that we can use one single cervical cancer to use to predict for four cancers – womb, breast,’ she told the Daily Mail.
‘These look for methylation signatures so factors that drive cancer in other tissues like breast and ovaries so lifetime exposure to hormones can also be read out by the methylation signature in the cervical cells.
‘We call it a surrogate effect. So instead of needing a test for each, you only need one.
‘It sounds futuristic but I hope we can implement this soon.’
Professor Martin Widschwendter, from University College London’s department of women’s cancer, has been working on this research for two decades.
He said: ‘Vaccination against the virus that causes cervical cancer is now widely implemented and is leading to changes in the amount and types of the virus circulating in the community.
‘In turn, our approaches to cervical screening must adapt so that programmes continue to deliver benefit.
‘Importantly, our other work has shown how testing the same cervical sample can also deliver information on a woman’s risk of three other major cancers – breast, ovarian and womb cancers.
‘Building new, holistic, risk-predictive screening programmes around existing, effective cervical sample collection offers real potential for cancer prevention in the future.’
There are around 3,200 new cases of cervical cancer each year in the UK and around 850 deaths.
Roughly 14,000 women are struck down with the disease every year in the US, and it kills up to 4,000.
Around half of women with the disease survive for 10 years or more.
Athena Lamnisos, chief executive of the Eve Appeal charity, said: ‘It’s so welcome to see screening tools and predictive tests becoming more effective.
‘We want to prevent cancer – and we know with cervical cancer that we can intervene at an early stage.
‘This new method is more specific and doesn’t lead to over-treatment which is good news for cervical cancer prevention and great news for everyone who needs to be screened.’
WHAT IS CERVICAL CANCER?
Cervical cancer affects the lining of the lower part of womb.
The most common symptom is unusual bleeding, such as between periods, during sex or after the menopause, but other signs can include:
- Pain during sex
- Vaginal discharge that smells
- Pain in the pelvis
Causes can include:
- Age – more than half of sufferers are under 45
- HPV infection – which affects most people at some point in their lives
- Smoking – responsible for 21 per cent of cases
- Contraceptive pill – linked to 10 per cent of cases
- Having children
- Family history of cervical or other types of cancer, like vagina
