The NHS vaccination programme to prevent cervical cancer has so far stopped hundreds of women from developing the disease and thousands from experiencing pre-cancerous changes to cells, a study has found.
In the first proof that the programme is working to save lives, the Cancer Research UK-funded study found that cervical cancer rates in women offered the human papillomavirus (HPV) vaccine between the ages of 12 and 13 (now in their 20s) were 87% lower than in an unvaccinated population.
Researchers said cases in this age group, which are rare, dropped from about 50 per year to just five.
There were also reductions in cervical cancer rates of 62% in women offered vaccination between the ages of 14 and 16, and 34% in women aged 16 to 18 when vaccination was introduced.
Experts looked at data from the HPV immunisation programme using the vaccine Cervarix, which was given to girls on the NHS from 2008 to September 2012.
A different vaccine, Gardasil, is now used for the programme, and is given to girls and boys aged 12 and 13.
The new study was able to use data to estimate that, by June 2019, there were around 450 fewer cases of cervical cancer (down to 374 cases in 2016-2018) and 17,200 fewer cases of cervical carcinomas (pre-cancers) than expected in those vaccinated against HPV in England.
The study found a 97% drop in pre-cancerous changes to cells in women vaccinated between the ages of 12 and 13, 75% in women vaccinated between the ages of 14 and 16, and 39% in women vaccinated between the ages of 16 and 18.
Without vaccination, experts believe the toll for pre-cancerous changes could have affected almost 36,000 women.
The researchers said the findings, published in The Lancet medical journal, provide the first direct worldwide evidence of prevention of cervical cancer using a vaccine for two types of HPV, which is the virus that causes it.
Cancer Research UK said the findings were better than expected and that cervical cancer could become a rare disease thanks to vaccines combined with screening.
Professor Peter Sasieni, lead study author, from King’s College London, said: “It’s been incredible to see the impact of HPV vaccination and now we can prove it prevented hundreds of women from developing cancer in England.
“We’ve known for many years that HPV vaccination is very effective in preventing particular strains of the virus, but to see the real-life impact of the vaccine has been truly rewarding.
“Assuming most people continue to get the HPV vaccine and go for screening, cervical cancer will become a rare disease.
“This year we have already seen the power of vaccines in controlling the Covid-19 pandemic. These data show that vaccination works in preventing some cancers.”
Dr Vanessa Saliba, consultant epidemiologist for UKHSA, which also took part in the study, said: “These remarkable findings confirm that the HPV vaccine saves lives by dramatically reducing cervical cancer rates among women.
“We encourage all who are eligible for the HPV vaccine to take it up when it is offered in school. All those eligible can catch up until their 25th birthday.
“Together with cervical screening, this will help to protect more women from preventable cases of cervical cancer.”
Cancer Research UK chief executive Michelle Mitchell said: “Results like this show the power of science.
“It’s a historic moment to see the first study showing that the HPV vaccine has and will continue to protect thousands of women from developing cervical cancer.”
At the moment in the UK, around 3,200 cases of cervical cancer are diagnosed each year.
The study looked in detail at cancer registry data between January 2006 and June 2019 for seven groups of women who were between the ages of 20 and 64 at the end of 2019.
The National Cancer Registration and Analysis Service (NCRAS) run by NHS Digital also took part in the study.