Five-year intervals between cervical cancer screenings are safe for women who test negative for human papillomavirus (HPV).
The study of 1.3 million women in England provides evidence that a longer gap between smear tests where HPV has not been detected, prevents as many cancers as screening at three-year intervals, even if women are not vaccinated against HPV.
Published in the British Medical Journal and funded by Cancer Research UK, the findings show that testing for HPV first can reduce the risk of developing dangerous cervical lesions and cervical cancer by half in women aged 24-49 years old.
Most cervical cancers are caused by HPV infection, which can cause abnormal cells to develop in the cervix. If these abnormal cells are not treated, they can turn into cancer. Before 2019, cytology tests, also known as smear tests, would be used to detect abnormal cells, and if found, the samples would be tested for HPV. Now samples taken during cervical screening are tested for HPV first since having the HPV infection comes before having abnormal cells.
Researchers from King’s, the University of Manchester, and the NHS analysed data from the NHS Cervical Screening Programme in England. They followed people attending screening for two rounds. The first screening was between 2013-2016, with a follow up by the end of 2019.
People who had a negative HPV in the first round had a lower risk of detecting clinically relevant cervical lesions (known as CIN3+) in the second round, compared to those who had a cytology test in the first round. After a negative HPV screen, 1.21 in 1,000 people had a detection of CIN3+, compared to 4.52 in 1,000 people after a negative smear test.
Lead author Dr Matejka Rebolj, from King’s College London, said: ‘These results are very reassuring. Changing to five-yearly screening will mean we can prevent just as many cancers as before while allowing for fewer screens.’
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.’
She added: ‘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 changes to the screening programmes are made, they will be monitored to help ensure that cervical screening is as effective as possible for all who take part.’
This comes after people missed their cervical screening appointment were urged to contact their GP practice in February this year, after data revealed nearly a third of those eligible did not come forward in 2020 to 2021.