Cancer | 2021
Lower Cervical Cancer Risk Associated With HPV Vaccine
Abstract
A Swedish study that over the course of 11 years followed 1.7 million women between the ages of 10 and 30 years showed that those who were vaccinated against HPV had a significantly lower risk of developing cervical cancer. The research was published last year in The New England Journal of Medicine.1 This is the first time that researchers have demonstrated at a population level that HPV vaccination is protective against cellular changes that can lead to cervical cancer and against invasive disease according to Jiayao Lei, a PhD student and researcher in the Department of Medical Epidemiology and Biostatistics at Karolinska Institutet in Solna, Sweden. This is mostly because the HPV vaccine is still relatively new, and invasive cervical cancer takes time to develop, usually not appearing until women are in their 30s or 40s, according to Elise C. Kohn, MD, National Cancer Institute senior investigator and head of Gynecologic Cancer Therapeutics. In this study, more than 500,000 women were vaccinated with the quadrivalent HPV vaccine from 2006 to 2017. The majority of them received the vaccine before the age of 17 years. In the vaccinated group, 19 women were diagnosed with cervical cancer, whereas 538 women were diagnosed with the disease in the unvaccinated group. The cumulative incidence of cervical cancer was 47 and 94 women per 100,000, respectively. Girls who were vaccinated before the age of 17 years had an 88% cervical cancer risk reduction, and women vaccinated between the ages of 17 and 30 years experienced half the risk for cervical cancer in comparison with those who were not vaccinated against HPV, the study found. Study coauthor Pär Sparén, PhD, a professor in the Department of Medical Epidemiology and Biostatistics at Karolinska Institutet, says the reason that girls who were vaccinated at a younger age seemed to be better protected from cervical cancer is that they were less likely to have been exposed to HPV infection before vaccination.