Cervical cancer screening intervals could be extended for women aged 30 and over if doctors used human papillomavirus (HPV) testing rather than smear tests, British scientists said on Wednesday.
Experts said research into different screening methods found that HPV tests were very accurate in picking up early signs of cervical cancer and detected more serious abnormalities than conventional smear tests in women aged 30 and over.
“Using HPV testing as the primary screening method for cervical cancer would not only mean women could be screened less often but it would also mean efficiency savings,” said Jack Cuzick, a professor of epidemiology at Queen Mary, University of London, who worked on the study.
HPV is the most common sexually transmitted infection in the world. There are more than 100 types of the virus, some of which cause only genital warts but others cervical cancer.
According to the World Health Organisation, cervical cancer is the second biggest cause of female cancer deaths worldwide with about 288,000 deaths each year.
Cervical screening programmes are well established in many wealthy nations and immunisation programmes against HPV with vaccines such as Cervarix and Gardasil are also being rolled out.
Cuzick’s study, which was published in the British Journal of Cancer, involved 11,000 women in the UK. Two samples were taken from each woman and one analysed using the conventional cytology method, while the other was sent for HPV testing.
Cytology involves an analysis of cervical cells taken during a smear test.
The results showed that women with HPV negative results had a lower rate of developing pre-cancerous cells for at least six years compared with women who recorded a negative cytology result, showing that HPV testing was more accurate.
A second study conducted by Finnish scientists, published in the British Medical Journal, showed that HPV testing is also better than cytology at detecting severe pre-cancerous lesions.
In a telephone interview, Cuzick said the evidence now showed clearly that regular testing programmes in all countries that conduct them should be swap to using HPV tests.
“There is now an overwhelming case for moving to HPV as the primary screening test,” he said. “If you have a test that gets it right the first time, you can also increase the gap between screens, saving doctors’ time.”
Current policy in Britain is to test using cytology every three years from age 30 to 50 and then every 5 years for older women. In the United States, smear tests are recommended every two years from age 21 to 30 and every three years beyond that.
Cervical cancer is a slow-growing cancer, which means that more accurate HPV screening would only need to be done about every five years to be effective, Cuzick said.
By Kate Kelland