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If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.
Human papillomavirus is a sexually transmitted infection (STI) that affects 14 million people in the U.S. each year (CDC, 2018). HPV is so common that over 80% of Americans will get infected at some point in their lives. Not only does it cause genital warts, but HPV is also implicated in several cancers, including cervical cancer and oropharyngeal cancer. Cancer of the oropharynx refers to cancers of the back of the throat, including the tongue base and tonsils. The incidence of HPV-associated OPC has increased from 16% to 73% over the past 20 years. OPC is now the most prevalent HPV-associated cancer in the U.S. (surpassing cervical cancer) (Berman, 2017).
Risk factors for oropharyngeal cancer (OPC)
Oral HPV is the most significant risk factor for oropharyngeal cancer; however, there are other risk factors to consider:
- Oral sex—People who engage in oral sex are more likely to get HPV-related OPC (Gillison, 2008).
- Multiple sex partners—The greater the number of sexual (especially oral sex) partners you have, the more likely you are to get oral HPV, thereby increasing your risk of oropharyngeal cancer (Moore, 2015).
- Tobacco use—Smoking allows cancer-causing chemicals (carcinogens) to enter your body. They can lead to cancer by affecting the DNA in your cells and by weakening your immune system so that it is not as effective in fighting off oral HPV. Also, smokers have a higher risk of dying from OPC than non-smokers (Moore, 2015).
- Drinking alcohol—People with significant alcohol intake have a higher risk of getting oropharyngeal cancer; this is especially true in heavy drinkers who also smoke cigarettes.
- Open mouth kissing—It is theorized that deep open mouth kissing may be another way to spread oral HPV from one person to another; more research is needed in this area (Dahlstrom, 2014).
- Male gender—Men are four times more likely to have oral HPV than women.
Oral HPV and oropharyngeal (mouth/throat cancer)
Tobacco and alcohol were thought to be the leading causes of oropharyngeal cancer, but now 70-80% of OPC is linked to HPV, while tobacco and alcohol use account for the remaining 20-30% (Berman, 2017). According to the Centers for Disease Control and Prevention (CDC), approximately 10% of men and 3.6% of women have oral HPV (CDC, 2018). Most healthy people can clear an HPV infection within two years, but sometimes the virus can linger. When this happens, especially if you have HPV type 16, you are at an increased risk of getting oropharyngeal cancer.
Human Herpesvirus 6 (HHV-6): transmission and symptoms
HPV type 16 is known as “high risk” HPV because it has been found to cause not only oropharyngeal cancer, but also cervical cancer, anal cancer, and penile cancer. On any given day in the U.S., approximately 26 million people have oral HPV, and 1% of them have HPV-type 16 (OCF, 2019). The CDC estimates that a little over 2,000 women and 11,000 men get HPV-related oropharyngeal cancer per year (CDC, 2018).
Unlike cervical cancer, there is no screening test for oropharyngeal cancer. If your healthcare provider finds a suspicious lesion, a small sample of tissue can be collected and tested (biopsy). There are over 100 types of HPV, and only a few cause oral cancer. However, you can get warts in your mouth/throat that are not cancerous, especially if you have oral HPV types 6 and 11.
Oral HPV usually does not cause symptoms until it develops into a disease like warts or cancer. Symptoms of oropharyngeal cancer include (Moore, 2015):
- A mass or tumor in your neck
- Abnormal lesions in your mouth or throat
- Persistent sore throat or hoarseness
- Difficulty or pain with swallowing; it may feel like there is something stuck in the back of your throat
- Constant earache on one side
HPV and genital warts: 2 strains cause 90% of them
The HPV vaccine and oral cancer
The FDA has approved three HPV vaccines for use in boys and girls aged 9-26: Gardasil, Gardasil-9, and Cervarix. Recently, Gardasil-9 was also approved for unvaccinated adults up to age 45. The HPV vaccine works against the high-risk HPV types 16 and 18 that are linked to most of the HPV-associated cancers (including OPCr) and types 6 and 11 (associated with genital warts). Studies in both the U.S. and Costa Rica have shown a decrease in the prevalence of oral HPV types 16, 18, 6, and 11; there was an 88% reduction in these HPV types in vaccinated men and women in the U.S. and a 93% reduction in vaccinated women in Costa Rica (Chaturvedi, 2018; Beachler, 2015).
The HPV vaccine was initially developed to combat cervical cancer, and it is not specifically approved to prevent oropharyngeal cancer. However, there is growing evidence that by preventing infection with the high-risk HPV strains, it may decrease the risk of HPV-associated oropharyngeal cancer as well. More research needs to be done to see if vaccine use leads to a decrease in OPC rates. Other means of prevention include using safe sex practices (condoms or dental dams), having fewer sexual partners, avoiding tobacco use, and limiting alcohol consumption.
- Beachler, D. C., Kreimer, A. R., Schiffman, M., Herrero, R., Wacholder, S., Rodriguez, A. C., et al. (2015). Multisite HPV16/18 Vaccine Efficacy Against Cervical, Anal, and Oral HPV Infection. Journal of the National Cancer Institute, 108(1). doi: 10.1093/jnci/djv302. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/26467666
- Berman, T. A., & Schiller, J. T. (2017). Human papillomavirus in cervical cancer and oropharyngeal cancer: One cause, two diseases. Cancer, 123(12), 2219–2229. doi: 10.1002/cncr.30588. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/28346680
- Centers for Disease Control and Prevention (CDC). (2018). About HPV. Retrieved September 20, 2019 from https://www.cdc.gov/hpv/parents/about-hpv.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fhpv%2Fparents%2Fwhatishpv.html
- Centers for Disease Control and Prevention (CDC). (2018). HPV and Oropharyngeal Cancer. Retrieved September 20, 2019 from https://www.cdc.gov/cancer/hpv/basic_info/hpv_oropharyngeal.htm
- Chaturvedi, A. K., Graubard, B. I., Broutian, T., Pickard, R. K., Tong, Z.-Y., Xiao, W., et al. (2018). Effect of Prophylactic Human Papillomavirus (HPV) Vaccination on Oral HPV Infections Among Young Adults in the United States. Journal of Clinical Oncology, 36(3), 262–267. doi: 10.1200/jco.2017.75.0141. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/29182497
- Dahlstrom, K. R., Burchell, A. N., Ramanakumar, A. V., Rodrigues, A., Tellier, P.-P., Hanley, J., et al. (2014). Sexual Transmission of Oral Human Papillomavirus Infection among Men. Cancer Epidemiology Biomarkers & Prevention, 23(12), 2959–2964. doi: 10.1158/1055-9965.epi-14-0386. Retrieved from https://cebp.aacrjournals.org/content/23/12/2959
- Moore, K. A., & Mehta, V. (2015). The Growing Epidemic of HPV-Positive Oropharyngeal Carcinoma: A Clinical Review for Primary Care Providers. The Journal of the American Board of Family Medicine, 28(4), 498–503. doi: 10.3122/jabfm.2015.04.140301. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/26152442
- Oral Cancer Foundation (OCF). (2019). HPV / Oral Cancer Facts. Retrieved September 20, 2019 from https://oralcancerfoundation.org/understanding/hpv/hpv-oral-cancer-facts/
Dr. Tzvi Doron is Board Certified in Family Medicine by the American Board of Family Medicine and is Ro's Chief Clinical Officer.