Almost 2,500 cases of cervical cancer among Irish women could be prevented in the coming decades by scaling up vaccination and screening rates, according to a major international study.
Cervical cancer could be eliminated as a public health problem in Ireland by 2060 by increasing the take-up of the HPV vaccine and switching to improved testing methods, the study published in The Lancet Oncology journal suggests.
Globally, the disease could be eliminated in most countries by the end of the century, with up to 13.4 million cases prevented by improved screening and vaccine coverage.
This estimate is based on switching to a vaccine for girls that protects against nine strains of the human papillomavirus (HPV); the vaccine currently used in Ireland protects against only four strains.
It also assumes a switch to HPV testing for cervical cancer, which is more effective, reliable and adaptable than traditional screening methods such as smear tests. However, the promised introduction of HPV testing in Ireland has been delayed by an ongoing backlog of almost 80,000 smear tests in the CervicalCheck programme.
The backlog arose after the Government last year offered women free out-of-cycle tests to alleviate anxiety in the wake of the controversy around CervicalCheck. This has to be cleared before HPV testing can be introduced, a process that may take up to a year.
The Lancet study estimates 2,440 of the 14,546 cases expected in Ireland between 2020 and 2069 could be averted through enhanced screening and vaccine coverage.
Its estimate is based on a 77 per cent uptake of the HPV vaccine at present, though a footnote records Ireland has experienced a drop in coverage that is not explicitly captured in the analysis. In fact, coverage dropped to 52 per cent in 2017 due to criticism of the vaccine, although this was unsupported by scientific evidence. It has since recovered to 65 per cent.
The Health Information and Quality Authority (Hiqa) last December recommended the HPV vaccine be extended to teenage boys as well as girls and that the four-valent vaccine be replaced by a nine-valent one. The Department of Health says a policy decision has been made to introduce these changes next September.
Global figures
The study estimates that without expanding current prevention programmes, 44.4 million cervical cancer cases would be diagnosed globally over the next 50 years – rising from 600,000 in 2020 to 1.3 million in 2069 due to population growth and ageing.
Two-thirds of these cases, and an estimated 15 million deaths, would occur in countries with low and medium levels of development.
“A failure to expand current programmes to reach the women who would most benefit from cervical cancer prevention strategies will have devastating consequences,” the study warns.
The estimates by the US, Australian and French researchers suggest that with proper intervention, the average rate of annual cases across all countries could fall to less than four per 100,000 women by the end of the century – considered the threshold for cervical cancer to be eliminated as a major public health problem.
"Despite the enormity of the problem, our findings suggest that global elimination is within reach with tools that are already available, provided that both high coverage of HPV vaccination and cervical screening can be achieved," said Prof Karen Canfell from the Cancer Council New South Wales in Australia, who led the study.
