The Quarterly Consult is a quarterly publication highlighting pediatric clinical expertise. If you would like to submit questions for a specialist at Children's to address in the Quarterly Consult, contact Kim Arthur, editor.
April 2012: HPV Vaccination for Boys
Dr. Rachel Katzenellenbogen, an infectious disease researcher at Seattle Children's, addresses questions about the new American Academy of Pediatrics policy statement recommending vaccinations against human papillomavirus (HPV) for boys. Thank you to Dr. Matt Allen, a pediatrician at Ballard Pediatrics and a member of Children's medical staff, for submitting these questions.
Q. What cancers is HPV associated with in boys or men?
A. HPV is associated with several cancers in men, including anal cancer, penile cancer and head and neck cancers.
Q. What data is available regarding protection from each of these cancers after receiving the HPV vaccine?
A. Currently, the only data is on anal cancer in men. A 2011 study by Palefsky et al. found that there was protection against a precursor of anal cancer called anal intraepithelial neoplasia (AIN) in 16- to 26-year-old males who were vaccinated with quadrivalent vaccine, which protects against HPV 6, 11, 16 and 18.
The data was drawn from a large international population of men, focusing on a subset of men who have sex with men. The protection against AIN was 77% in the per-protocol cohort, which represents the level of protection we would expect if children and adolescents are vaccinated early.
One of the main reasons the vaccination's effectiveness was studied in men who have sex with men is because they have a very high risk of anal cancer. However, all men (and women) are at risk for anal cancer.
With respect to antibody response to the vaccination, Block et al. showed that the response is better in male and female research participants ages 9 to 15 compared to women ages 16 to 26, which was the original group that the vaccination was approved for by the Food and Drug Administration.
Q. What is the data regarding protection from male genital warts?
A. In the same 2011 study by Palefsky et al., the vaccination was 90% effective in preventing external genital lesions (including warts) in the per-protocol cohort in all men.
Q. What are the potential side effects of the vaccination and rates?
A. The side effect profiles and rates in boys and girls are similar. The side effects include local swelling and irritation at the site and occasionally headaches. According to Block et al., headaches have been reported in 23% of boys and girls ages 9 to 15 who were vaccinated, and fever has been reported in 13%.
Q. What talking points would you suggest for counseling patients and parents?
A. Getting vaccinated is important because most men and women get infected with HPV during their lifetime. People may not realize they have an infection if they don't have a wart or precancerous lesion, but it's very common.
If men are sampled across their whole age range, there are studies that show that 50% to 70% of men have evidence of an HPV infection, according to a study by Anic and Giuliano. Women tend to get HPV infections soon after sexual debut, but their infection rates tend to taper as women age, whereas these rates stay high in men. While most people are able to clear the infection, it's impossible to predict who can and can't clear it.
Cancer prevention is an important reason to get the vaccination, but it's also important because it can prevent external genital lesions and warts in both men and women, and HPV can be spread from an external genital wart. Treatment for external genital lesions is quite painful, and it can be stressful psychologically.
Head and neck cancers, which are associated with HPV, are increasing in men and women. Head and neck cancers historically have been associated with smoking and drinking alcohol, but now they are increasingly associated with HPV infections, likely due to oral sex. Chaturvedi et al. reported that head and neck cancers are likely to become more common than cervical cancer by 2020 in the United States.
I'm pleased that the American Academy of Pediatrics (AAP) and the Advisory Committee on Immunization Practices are recommending the HPV vaccination for males and females. It allows for equal preventive care, regardless of gender, and regardless of preconceived notions about anyone's future behavior.
HPV is the most common sexually transmitted infection, and the majority of us get it, so there is nothing specific about any individual's behavior that would put them at more risk. It's important for boys and girls to get the vaccination at a young age before exposure, just like people get vaccinations before traveling to areas where an infectious disease is common.
- Anic, G. M. and A. R. Giuliano. 2011. Genital HPV infection and related lesions in men. Prev.Med. 53 Suppl 1:S36-41.:S36-S41.
- Block, S. L., T. Nolan, C. Sattler, E. Barr, K. E. Giacoletti, C. D. Marchant, X. Castellsague, S. A. Rusche, S. Lukac, J. T. Bryan, P. F. Cavanaugh, Jr., and K. S. Reisinger. 2006. Comparison of the immunogenicity and reactogenicity of a prophylactic quadrivalent human papillomavirus (types 6, 11, 16, and 18) L1 virus-like particle vaccine in male and female adolescents and young adult women. Pediatrics. 118:2135-2145.
- Chaturvedi, A. K., E. A. Engels, R. M. Pfeiffer, B. Y. Hernandez, W. Xiao, E. Kim, B. Jiang, M. T. Goodman, M. Sibug-Saber, W. Cozen, L. Liu, C. F. Lynch, N. Wentzensen, R. C. Jordan, S. Altekruse, W. F. Anderson, P. S. Rosenberg, and M. L. Gillison. 2011. Human papillomavirus and rising oropharyngeal cancer incidence in the United States. J.Clin.Oncol. 29:4294-4301.
- Giuliano, A. R., J. M. Palefsky, S. Goldstone, E. D. Moreira, Jr., M. E. Penny, C. Aranda, E. Vardas, H. Moi, H. Jessen, R. Hillman, Y. H. Chang, D. Ferris, D. Rouleau, J. Bryan, J. B. Marshall, S. Vuocolo, E. Barr, D. Radley, R. M. Haupt, and D. Guris. 2011. Efficacy of quadrivalent HPV vaccine against HPV Infection and disease in males. N.Engl.J.Med. 364:401-411.
- Nyitray, A., C. M. Nielson, R. B. Harris, R. Flores, M. Abrahamsen, E. F. Dunne, and A. R. Giuliano. 2008. Prevalence of and risk factors for anal human papillomavirus infection in heterosexual men. J.Infect.Dis. 197:1676-1684.
- Palefsky, J. M. 2010. Human papillomavirus-related disease in men: not just a women's issue. J.Adolesc.Health. 46:S12-S19.
- Palefsky, J. M., A. R. Giuliano, S. Goldstone, E. D. Moreira, Jr., C. Aranda, H. Jessen, R. Hillman, D. Ferris, F. Coutlee, M. H. Stoler, J. B. Marshall, D. Radley, S. Vuocolo, R. M. Haupt, D. Guris, and E. I. Garner. 2011. HPV vaccine against anal HPV infection and anal intraepithelial neoplasia. N.Engl.J.Med. 365:1576-1585.