The long term findings of a study carried out at Hammersmith hospital reveal that testing for Human Papilloma Virus (HPV) can be twice as effective at protecting women from developing cervical abnormalities as smear testing. Results of the research - led by Professor Jack Cuzick of Barts and The London School of Medicine and Dentistry - are published today (Thursday, 15 May 2008) in the International Journal of Cancer.
Nearly 3,000 women aged 35+ were recruited into the study between April 1994 and September 1997. They were asked to participate in a study in which HPV testing would be performed in addition to cytology (smear test) whilst attending their GP practice (40 practices were involved in the trial) for a routine cervical smear. Women who had previously been treated for cervical intra-epithelial neoplasia (CIN) - changes to cells in the cervix that can develop into cancer - or had experienced any cervical abnormality within the previous 3 years, were excluded from the study.
All women tested were followed up passively using data from the national computerised system that records all smears and their results - the Open-Exeter system. Women with a smear history indicating the need for colposcopy - a more thorough examination of the cervix - were investigated further to determine whether the colposcopy and biopsy were performed, and what the resultant outcome was. Passive follow-up was complete for all women by early 2005.
Results showed that the risk of developing cervical abnormalities at 1, 5, and 9 years after a normal smear test was 0.33 per cent, 0.83 per cent, and 2.20 per cent respectively, with those odds significantly reduced after a negative HPV test - 0.19 per cent, 0.42 per cent, and 1.88 per cent.
Professor Jack Cuzick said: "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 6 years after a negative test, compared to protection from a normal smear test which begins to wane after about 3 years. This suggests that the screening interval can be safely extended to at least 6 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."
Notes to editors:
Barts and The London School of Medicine and Dentistry
Barts and The London School of Medicine and Dentistry - at Queen Mary, University of London - offers international levels of excellence in research and teaching while serving a population of unrivalled diversity amongst which cases of diabetes, hypertension, heart disease, TB, oral disease and cancers are prevalent, within east London and the wider Thames Gateway. Through partnership with our linked trusts, notably Barts and The London NHS Trust, and our associated University Hospital trusts - Homerton, Newham, Whipps Cross and Queen's - the School's research and teaching is informed by an exceptionally wide ranging and stimulating clinical environment.
At the heart of the School's mission lies world class research, the result of a focused programme of recruitment of leading research groups from the UK and abroad and a £100 million investment in state-of-the-art facilities. Research is focused on translational research, cancer, cardiology, clinical pharmacology, inflammation, infectious diseases, stem cells, dermatology, gastroenterology, haematology, diabetes, neuroscience, surgery and dentistry.
The School is nationally and internationally recognised for research in these areas, reflected in the £40 million it attracts annually in research income. Its fundamental mission, with its partner NHS Trusts, and other partner organisations such as CRUK, is to ensure that that the best possible clinical service is underpinned by the very latest developments in scientific and clinical teaching, training and research.