Testing for human papillomavirus (HPV) infection as the first step in analysing cervical screening samples is practical and more sensitive than the current programme, a new pilot study has confirmed.
The research, published in The BMJ, also suggests that HPV primary testing could see the time between screenings extended to five years.
Plans are already underway to change the order in which samples are tested in the UK’s cervical screening programme. This would involve first testing samples for HPV, which is responsible for almost all cases of cervical cancer.
Weilin Wu, health information officer at Cancer Research UK, said that the study backs previous clinical trial results showing that testing for HPV first is a better way to screen for cell changes that may become cervical cancer.
Clinical trials show that testing samples for HPV first is much more effective at preventing cervical cancer than the current programme, which first looks for abnormal cells under a microscope (cytology).
To test the effectiveness of HPV primary screening in a real-world setting, researchers compared it to the current screening programme in six NHS laboratories in England.
A total of 578,547 women aged between 24 and 64 years old were included in the study, each undergoing routine cervical screening with either HPV testing or cytology. The women were followed up for around three years after screening.
In the HPV primary screening setting, samples that tested positive for HPV were then analysed under a microscope to look for cell changes. If abnormal cells were found, women were immediately referred for further testing.
If no abnormal cells were detected, women were asked to return in 12 months for another test. Eight in 10 women attended this follow-up appointment.
Women who tested negative for HPV didn’t have any further tests and were invited for screening three years later. Researchers found that this method of screening was significantly better at picking up cell changes that could lead to cancer than the current programme.
The increased sensitivity of HPV primary testing was seen three years later when participants were screened again. Women who had their samples tested for HPV first were far less likely to have abnormal cell changes when screened a second time.
The researchers now suggest that the time between screening invitations could be increased from three to five years as a result. The UK National Screening Committee, which decides how the national screening programmes should be run, is investigating extending the time between screening. The committee is expected to publish its recommendation in April.
HPV primary screening has already been rolled out in Wales and will be introduced in England at the end of 2019 and in Scotland in 2020.
Wu said that the next step is for the government to roll out HPV screening as scheduled later this year. He also stressed the importance in raising awareness that HPV is a common virus that doesn’t usually cause problems.