HPV test may offer 'better protection' than smear test
British scientists have found that testing for human papillomavirus (HPV), the virus that causes most cases of cervical cancer, may be a more effective way of protecting women against the disease than the existing cervical smear test.
The UK's cervical cancer screening programme invites women between the ages of 25 and 60 to have a smear test at least every five years which looks for pre-cancerous changes in the cells of the cervix.
Experts are currently considering whether HPV testing should be made routinely available on the NHS for women with borderline smear tests to help determine whether they should have treatment for these cell changes.
A study carried out at Hammersmith Hospital has now revealed that testing for HPV can be twice as effective at protecting women from developing cervical abnormalities as smear testing.
Researchers recruited nearly 3,000 women over the age of 35 between April 1994 and September 1997, none of whom had received treatment for pre-cancerous cells in the cervix during the previous three years.
Participants underwent HPV testing alongside their regular smear tests and their results were then analysed.
Experts found that the risk of developing cervical abnormalities after a normal smear test was 0.33 per cent at one year, 0.83 per cent at five years, and 2.2 per cent at nine years.
After a negative HPV test, the risk of developing cervical abnormalities was significantly reduced - 0.19 per cent after one year, 0.42 per cent after five years, and 1.88 per cent after nine years.
Lead researcher Professor Jack Cuzick, of Barts and the London School of Medicine and Dentistry, commented: "Not only does the research confirm that HPV testing detects more disease at each smear, it shows that this approach offers women excellent protection from cervical abnormalities for at least six years after a negative test, compared to protection from a normal smear test which begins to wane after about three years.
"This suggests that the screening interval can be safely extended to at least six years with HPV testing. These data provide more support for replacing screening based on abnormal cells, with a more sensitive test based on screening for the human papillomavirus," he added.
Commenting on the findings, which are published in the International Journal of Cancer, Cancer Research UK's Dr Kat Arney said: "When considering large-scale public health initiatives such as cervical cancer screening, it is important to base decisions on solid scientific research.
"This finding adds to the evidence suggesting that HPV testing could be used instead of the current cervical smear tests for women over 35, although larger studies still need to be done to show that this can actually reduce the number of women who end up being diagnosed with cervical cancer."
Cancer Research UK added that it is still important for women to go for cervical screening when invited, despite the recent introduction of an HPV vaccination programme which is being given to girls under 18 years of age and will protect against most cases of cervical cancer.