New 5-yearly HPV screening policy in Australia
The new 5-yearly HPV screening policy in Australia
may reduce protection from cervical cancer
From; Brian Cox,
Associate Professor of Cancer Screening and Cancer Control
Hugh Adam Cancer Epidemiology Unit
Department of Preventive and Social Medicine
Dunedin School of Medicine
University of Otago
and Specialist in Public Health Medicine
The aim of cervical screening is to reduce the incidence of cervical cancer. Evidence of a greater reduction in the incidence of cervical cancer is necessary before screening policy is altered. Evaluation of the new Australian 5-yearly HPV screening policy for cervical cancer conducted by Research Associate Professor Brian Cox and Dr Mary Jane Sneyd of the Hugh Adam Cancer Epidemiology Unit of the Department of Preventive and Social Medicine in Dunedin, New Zealand, suggests that the screening policy of 5-yearly HPV testing being adopted in Australia will reduce overall protection from cervical cancer in women screened by 121% compared to 2-yearly cervical smears and produce a 39% increase in long-term cervical cancer incidence.1 As New Zealand is introducing similar 5-yearly HPV screening soon we can also expect an reduction in the protection from cervical cancer for women.
The new 5-yearly HPV screening policy being introduced in New Zealand has relied heavily on the prediction of the effects of screening from a surrogate measure, high grade abnormalities of the cervix, rather than the effects on cervical cancer.2
Professor Cox says, "The effectiveness of the HPV test to detect the high grade abnormalities that actually develop into cancer has been inflated in the Australian simulation study of screening used to underpin the new screening policy. This has occurred because the HPV test detection rate of all high grade abnormalities, and not the lower detection rate of only those that would develop into cervical cancer, has been used in for the screening policy. The HPV detection rate of those that would develop into cervical cancer has been shown in several trials to be only similar to, and not better than, that achieved by cervical smears."
Professor Cox and Dr Sneyd agree with Finnish investigators, Professor Malila, Professor Hakama and colleagues, recognised world experts in cervical cancer screening, who found no improved reduction in risk of cervical cancer from 5-yearly HPV screening compared to 5-yearly cervical smears. They concluded, "Therefore, implementing HPV testing in routine screening programmes needs to be reconsidered especially in countries with organised programmes and a high quality infrastructure."3
Professor Cox says, "The current evidence suggests that increasing the screening interval from 3-yearly cervical smears to 5-yearly HPV testing may significantly reduce a woman's protection from cervical cancer. There are specific methods by which the introduction of a new screening policy can occur that allow the comparison of the ability of two screening tests to reduce cervical cancer and these are vita for the safe introduction of any new screening policy. The medical principle of "first do no harm" should be foremost so that the no increased risk to women occurs from replacing 3-yearly cervical smears with 5-yearly HPV testing ."
results of Professor Cox and Dr Sneyd have also been
recognised as part of successful advocacy to change the
draft cervical screening recommendations in the United