Disclosure: Chan discloses speaking and consulting fees from AstraZeneca and GSK, speaking fees from Eisai and Merck, and consulting fees from Immunogen and Seagen outside of the submitted work. The relevant financial information of all other authors can be found in the study.
A decline in cervical cancer rates in the United States, particularly among younger women, may be associated with approval of an HPV vaccine, according to a retrospective cross-sectional study published in JAMA network open.
The researchers added that an increase in oropharyngeal and anal/rectal cancers, particularly in men, underscores the need for vaccination in both men and women.
“Approximately 45,000 HPV-related cancers are diagnosed in the United States each year, and most of these cancers could have been prevented. The HPV vaccine was approved by the U.S. Food and Drug Administration for women in 2006 and for men in 2009 and provides protection against 90% of the HPV strains that cause cervical cancer.” John K. Chan, MD, Denise & Prentis Cobb Hale, endowed professor at California Pacific Medical Center and principal investigator for the Sutter Cancer Research Consortium, said Healio. “Because some of these cancers can be prevented by vaccination and/or screening, it is important to include both of these interventions in our study.”
The analysis included 657,317 HPV-associated cancers (oropharyngeal squamous cell carcinoma [SCC], 40%; anal/rectal SCC, 14.5%; vulvar SCC, 9.1%; vaginal SCC, 2%; cervical carcinoma, 31.4%; and penile SCC, 3%) identified between 2001 and 2017 from the US Cancer Statistics Public Use Database. Most cancers (59.8%) occurred in women, and 76.1% of all patients were white. More than half of the women (52.4%) had cervical cancer and most men (80.1%) had oropharyngeal cancer.
Researchers collected HPV vaccination and screening data from Behavioral Risk Factor Surveillance between 2001 and 2016 and from TeenVaxView between 2008 and 2018. They then assessed trends in HPV-associated cancer incidence by age, race and ethnicity, and tumor stage Potential associations between screening and vaccination with the incidence of HPV-associated cancers.
Among female adolescents aged 13 to 17 years, immunization coverage increased from 37.2% in 2008 to 69.9% in 2018 (annual percentage change 6.57%; 95% CI 5.83-7.32) .
The researchers also reported that rates of cervical cancer decreased by 2.29% per year (P = 0.045) in women aged 20 to 24 years before the vaccine was approved and 9.5% per year (P = .003) after approval.
In men, the researchers observed an annual increase in oropharyngeal (2.71%) and anal/rectal (1.83%) cancers. In women, the incidence of oropharyngeal cancer had remained stable, but the incidence of anal/rectal cancer increased by 2.83% annually. The higher median age of onset of anal/rectal cancer versus cervical cancer (62 years versus 49 years) may partly account for the continued increase in the incidence of anal/rectal cancer and the apparent lack of potential benefit from vaccination.
John K Chan
“Although the HPV vaccine has been approved in women for more than 15 years, uptake has been slower than other recommended vaccines for children,” Chan told Healio. “We did not expect to show that more than 80% of new oropharyngeal cancer diagnoses were in men, and the rate is increasing.”
Chan said more work is needed to increase vaccination rates in both sexes, in addition to efforts to eliminate racial and ethnic disparities in screening in the US
“These findings on the increasing incidence of anal/rectal cancer underscore the importance of HPV vaccination and the need to develop more effective screening strategies to prevent anal/rectal cancer, particularly in high-risk populations,” said Chan. “We want to promote better access to population-based studies with data sharing and develop a national screening and vaccination registry for cancer prevention.”
For more informations:
John K Chan, MD, reachable at California Pacific/Palo Alto Medical Foundation/Sutter Research Institute, 1100 Van Ness Ave., 4th Floor, San Francisco, CA 94109; Email: [email protected]