Vaccination protects against cancer caused by HPV infection

For the first time, it has been shown that vaccines against human papillomavirus (HPV) prevent malignant HPV-associated cancers in women. This was the finding of a Finnish-Swedish research team coordinated by the University of Tampere. The finding was based on registry monitoring of Finnish subjects in randomised HPV-vaccinated and control cohorts.

The subjects were monitored for HPV-associated cancers, which include cervical, vaginal, vulvar, anal and oropharyngeal cancers in women. No such cancers were found in more than 9,500 HPV-vaccinated subjects monitored for an average of seven years. In contrast, ten HPV-associated cancers, including eight cases of cervical cancer, were found in the non-vaccinated cohort of nearly 18,000 subjects during an equally long period of monitoring. This gives HPV vaccination a statistically significant efficacy of 100% against HPV-associated cancers (95% confidence interval: 16% to 100%).

The HPV-vaccinated women in this interim analysis received a series of three vaccine doses against two or four HPV types at 14–17 years of age. Women in the HPV-vaccinated and non-vaccinated cohorts born in 1984–1988 and 1992–1993 were of the same age during the monitoring period.

The evidence obtained from vaccination tests for the HPV vaccine’s effectiveness against malignant HPV-associated cancers is an ‘early’ result of sustained effort. The study cohorts were vaccinated against HPV in the years 2002–2008. It took a long time to establish the effectiveness of hepatitis B vaccine against liver cancer – 25 years from the first vaccinations.

A locally randomised study conducted by the Finnish-Swedish research team has recently shown that vaccinating both boys and girls against HPV also protects non-vaccinated individuals substantially better against cancer-inducing HPV types than vaccinating only girls. Just 75% HPV vaccination coverage for both sexes is sufficient to eradicate even the worst cancer-associated type, HPV16.

References:

  • Luostarinen T, Apter D, Dillner J, Eriksson T, Harjula K, Natunen K, Paavonen J, Pukkala E, Lehtinen M. Vaccination protects against invasive HPV-associated cancers. Int J Cancer. 2018 May 15;142(10):2186–2187. DOI: 10.1002/ijc.31231.