According to the projections of the population-based age-period-cohort study performed by a group of the authors from the Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health and Department of Otolaryngology–Head and Neck Surgery, Johns Hopkins University in Baltimore, MD, US who published their findings on 2 September 2021 in the JAMA Oncology, current human papillomavirus (HPV) vaccination rate will have a limited association with overall incidence of oropharyngeal cancer until 2045 because older individuals who are not vaccinated remain at high risk. Reductions in incidence of oropharyngeal cancer should occur among young and middle-aged adults, the group at lower risk of diagnosis. The findings from this study predict a shift in the oropharyngeal cancer landscape to an older population.
The authors performed this study because the incidence of oropharyngeal cancer has increased for several decades in the US, but it is unclear when and how this trend will be affected by current HPV vaccination trends. To assess the association of HPV vaccination with future incidence of oropharyngeal cancer in the US, the authors obtained the incidence data from the Surveillance, Epidemiology, and End Results programme from 69,562 patients who are 34 to 83 years old. The HPV vaccination data were obtained from 60,124 participants in the US National Immunization Survey–Teen and 16,904 participants in the US National Health Interview Survey.
Data were collected from 1992 to 2017. Age- and sex-specific cumulative prevalence of HPV vaccination in 2016 to 2017 were projected forward. Age-period-cohort forecasting models projected expected 2018 to 2045 incidence of oropharyngeal cancer under a counterfactual scenario of no HPV vaccination and current level of HPV vaccination, stratifying by sex. Data analyses were completed by the end of 2020.
The authors reported that under current HPV vaccination rate, they projected that the incidence of oropharyngeal cancer will decrease between 2018 and 2045 in younger individuals who are 36 to 45 years old, in particular, from 1.4 to 0.8 per 100 000 population, then from 8.7 to 7.2 per 100 000 population in those who are 46 to 55 years old, but it will continue to increase among older individuals who are 70 to 83 years old from 16.8 to 29.0 per 100 000 population.
The authors wrote that the association of HPV vaccination with overall incidence of oropharyngeal cancer through 2045 will remain modest, in case of no vaccination 14.3 per 100 000 population versus 13.8 per 100 000 population in case of vaccination.
By 2045, HPV vaccination is projected to reduce incidence of oropharyngeal cancer among individuals 36 to 45 years old, 48.1% in men and 42.5% in women, and in those who are 46 to 55 years old 9.0% in men and 22.6% in women, but among those 56 years or older, rates are not meaningfully reduced.
Between 2018 and 2045, a total of 6,334 cases of oropharyngeal cancer will be prevented by HPV vaccination, of which 88.8% of such cases occur in the groups younger than 55 years.
The authors concluded that their results suggest that it will take more than 25 additional years to slow an increasing incidence of oropharyngeal cancer by current HPV vaccination rate in the US because most disease will be among older individuals who have not yet been vaccinated.
Zhang Y, Fakhry C, D’Souza G. Projected Association of Human Papillomavirus Vaccination With Oropharynx Cancer Incidence in the US, 2020-2045. JAMA Oncology; Published online 2 September 2021. doi:10.1001/jamaoncol.2021.2907