Screening every five years safe for women who test negative for HPV, study confirms
A study of 1.3 million women in England has provided evidence to support the extension of cervical cancer screening intervals from three years to five years for those that have a negative screen result.
The study, published today in the British Medical Journal by researchers from King’s College London and funded by Cancer Research UK, provides reassurance to women and people with a cervix aged 24-49 years who test negative for the human papillomavirus (HPV), that screening at five-year intervals prevents as many cancers as screening at three-year intervals, even if they are not vaccinated against HPV.
The study confirms that women in this age group are much less likely to develop clinically relevant cervical lesions (high-grade cervical intraepithelial neoplasia, which are abnormal changes of the cells that line the cervix and are otherwise known as CIN3+) and cervical cancer, three years after a negative HPV screen compared to a negative smear test. This risk is more than halved.
Lead author Dr Matejka Rebolj, Senior Epidemiologist at King’s College London said: “These results are very reassuring. They build on previous research that shows that following the introduction of HPV testing for cervical screening, a 5-year interval is at least as safe as the previous 3-year interval. Changing to 5-yearly screening will mean we can prevent just as many cancers as before, while allowing for fewer screens.”
Almost all cervical cancers are caused by HPV infection. Usually, the immune system gets rid of the virus on its own, but if it doesn’t HPV can cause abnormal cells to develop in the cervix. If these abnormal cells are not treated, they can turn into cancer. This is a process that often takes 10-15 years, and sometimes even longer.
Before 2019, cytology tests, otherwise known as smear tests, checked cervical cells for abnormalities first. If found, some of the samples would then be tested for HPV. These tests were recommended every three years. In 2019, following expert scientific evidence, the NHS Cervical Screening Programme in England fully implemented primary high-risk HPV testing using cytology as a triage test, whilst keeping the same screening intervals (3 years for those aged 24-49 years). Now samples taken during cervical screening are tested for HPV first. As having HPV infection comes before having abnormal cells, HPV testing detects more women at risk of cervical cancer.
The study shows that the HPV test is more accurate than a cytology test. Researchers from King’s College London, the University of Manchester, and the NHS have analysed data the from the NHS Cervical Screening Programme in England. They followed those attending screening for two rounds, the first from 2013-2016 with a follow up by end of 2019.
Researchers found that people eligible for screening under fifty who had a negative HPV screen in the first round had a lower risk of detection of CIN3+ in the second round compared to cytology. 1.21 in 1000 people had a detection of CIN3+ after a negative HPV screen compared to 4.52 in 1000 people after a negative cytology.
Currently in the UK, where the HPV screen is negative, the NHS Cervical Screening Programme in England invites women and people with a cervix aged 25-49 years to test every three years and people aged 50-64 years to test every five years or three years if they test positive. Scotland and Wales are the first to implement the new intervals. England has introduced HPV testing but continue to invite those eligible under fifty every three years and over fifty to test every five years. Northern Ireland currently use cytology tests but will switch to HPV primary screening in the future.
Dr Rebolj added: “This monumental study relied on a multidisciplinary team including those in the NHS Cervical Screening Programme in England, working with women undergoing screening and their samples, and our academic partners. This partnership provides evidence that will best serve the millions of women invited for screening throughout most of their adult lives. These promising results show most women and people with a cervix do not need to be screened as frequently as they are now.”
Michelle Mitchell, Cancer Research UK’s chief executive, said: “This large study shows that offering cervical screening using HPV testing effectively prevents cervical cancer, without having to be screened as often. This builds on findings from years of research showing HPV testing is more accurate at predicting who is at risk of developing cervical cancer compared to the previous way of testing. As with any change to a screening programme, this will be monitored to ensure that cervical screening is as effective as possible for all who take part.
“It’s important to remember, screening is for people without symptoms. So, if you notice any unusual changes for you, do not wait for a screening invitation - speak to your doctor.”
ENDS
NOTES TO EDITORS:
About Cervical Screening & HPV
High-risk Human Papillomavirus (HPV) DNA is found in over 99% of all cervical cancers. Cervical screening now primarily tests for the presence of this high-risk HPV infection, which is a common virus that most people will get at some point. HPV primary screening is a more sensitive and accurate test than the previous method (cytology alone) and is the best way to find out who is at higher risk of developing the cervical cell changes that over time could potentially lead to cervical cancer.
While the risk for people with high-risk HPV of getting cervical cancer is low, any abnormal changes can be identified early. If HPV is detected, the sample is then checked for any changes in the cells of the cervix. Cell changes are easily treated if caught early, so they don’t get a chance to turn into cervical cancer.
For further information about cervical screening, please visit www.nhs.uk/cervicalscreening.
About extended screening intervals
- The National Screening Committee recommended that, following the introduction of primary HPV screening in the cervical screening programme screening invites should be changed from 3 to 5 years for 24.5 to 49 year olds for anyone that is found not to have high-risk HPV at their routine screening test.
- The NHS in England has not changed cervical screening invites to every five years for eligible people aged 24.5 to 49 years old if their screen shows they don’t have high-risk HPV.
- The NHS Cervical Screening Programme in England invites over 4.5m people each year. NHS Digital is working with NHS England and NHS Improvement at pace to prepare for the safe and smooth transition to a new IT system for cervical screening which would safely and effectively support any changes to the programme. This is a major piece of work which the programme is working closely with NHS Digital, to implement.
King’s College London
King's College London is one of the top 35 UK universities in the world and one of the top 10 in Europe (QS World University Rankings, 2020/21) and among the oldest in England. King's has more than 31,000 students (including more than 12,800 postgraduates) from some 150 countries worldwide, and some 8,500 staff.
King's has an outstanding reputation for world-class teaching and cutting-edge research. In the 2014 Research Excellence Framework (REF), eighty-four per cent of research at King’s was deemed ‘world-leading’ or ‘internationally excellent’ (3* and 4*).
Since our foundation, King’s students and staff have dedicated themselves in the service of society. King’s will continue to focus on world-leading education, research and service, and will have an increasingly proactive role to play in a more interconnected, complex world. Visit our website to find out more about Vision 2029, King's strategic vision to take the university to the 200th anniversary of its founding.
World-changing ideas. Life-changing impact: https://www.kcl.ac.uk/news/headlines.aspx
About Cancer Research UK
- Cancer Research UK is the world’s leading cancer charity dedicated to saving lives through research, influence and information.
- Cancer Research UK’s pioneering work into the prevention, diagnosis and treatment of cancer has helped save millions of lives.
- Cancer Research UK has been at the heart of the progress that has already seen survival in the UK double in the last 40 years.
- Today, 2 in 4 people survive their cancer for at least 10 years. Cancer Research UK wants to accelerate progress and see 3 in 4 people surviving their cancer by 2034.
- Cancer Research UK supports research into the prevention and treatment of cancer through the work of over 4,000 scientists, doctors and nurses.
- Together with its partners and supporters, Cancer Research UK is working towards a world where people can live longer, better lives, free from the fear of cancer.
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JOURNAL
BMJ
SUBJECT OF RESEARCH
People
ARTICLE TITLE
Extension of cervical screening intervals with primary human papillomavirus testing: observational study of English screening pilot data
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