by Margaret Scarlett, DMD: Captain, USPHS (ret.),
Centers for Disease Control and Prevention CEO
and President, Scarlett Consulting International
Much is known about the progression of human papillomavirus (HPV) in the genital tract. This
includes the association of high-risk HPV with cervical cancer and its prevention by the newly available
HPV vaccines. While long-term studies of the natural history of HPV within the oral cavity are not available,
it is known that the acquisition of HPV occurs through open-mouthed kissing and oral sex.1,2
Oral HPV infection, and especially infection with HPV-16, has been acknowledged as a risk factor for
developing oropharyngeal cancer, particularly oropharyngeal squamous cell carcinoma (OSCC) by the
International Agency for Research Against Cancer. A recently published study in the Journal of Emerging
Infectious Diseases suggests that there is a
slow epidemic of HPV infection-induced oral
cancers, notably OSCC.3
The incidence of these oral cancers, or
number of new cases diagnosed, has increased
significantly among persons between ages 20
and 39 in the U.S. Persons with prior HPV infections
are 32 times more likely to develop oral
cancers at the base of the tongue and tonsils
than those who do not.2,4 This is about 10 times
greater than the risk associated with chronic
alcohol or tobacco use.2
Throughout the last decade, the age at diagnosis, incidence, location of oral and pharyngeal cancers,
and risk factors have changed dramatically. From 1998 to 2003, differences in the type of oropharyngeal
cancers, the location and regional variations have been determined from epidemiologic data obtained
from national cancer registries and behavioral data. At least one published review of data demonstrates
that the incidence, or newly diagnosed cases of oral cancer at the tonsillar area and base of the tongue
are increasing.4 Several research studies, including at least one case control study, have suggested that
these changes might be attributed to the acquisition/transmission of HPV.1,2,3
While the science is evolving, dentists should carefully consider their role in the prevention of oral
cancers. This includes reviewing their oral cancer screening protocols periodically to include assessment
of HPV infection in the oral cavity.5 While there is limited data on oral practices, the highest-risk group is
expected among young sexually active adults under the age of 25. Since many of these young people are
otherwise healthy and do not regularly visit another primary care provider, dentists could play a significant
role in the prevention of a growing subset of oral cancers.
Therefore, dentists should assess and expand their capacity to provide HPV screening, appropriate
referral and counseling. They should be aware that open-mouthed kissing and oral sex carries some risk
of HPV transmission. This is likely to be greater, especially when one partner is known to be infected with
HPV, when either partner's HPV status is not known, and/or when one partner is not monogamous. Since
at least one study shows that persons with more than six oral sex partners are nine times more likely to
develop oral cancer than those who did not, dentists should evaluate their capacity to assess the patient's
oral practices for risk of acquiring HPV infection.2,5
Oral care providers should also determine their ability to provide appropriate training, counseling or
referral on oral sex practices, including the use of proper barrier protection and partner reduction to
reduce risk of HPV-associated oral cancers.5
References:
- D'Souza G, Fakhry C, Sugar E, Seaberg E, Weber K, Minkoff H, Anastos K, Palefsky J, Gillison ML. Six-month natural history of oral versus cervical
human papillomavirus infection. International Journal of Cancer. 2007;121:2897-904.
- D'Souza G, Kreimer AR, Viscidi R, Pawlita M, Fakhry C, Koch WM, Westra WH, Gillison ML. A case-control study of human papillomavirus and
oropharyngeal carcinoma. New England Journal of Medicine. 2007;356:1944-56.
- Ramqvist T, Dalianis T. Oropharyngeal cancer epidemic and human papillomavirus. Emerg Infect Dis [serial on the Internet]. 2010; Oct 29, 2010.
http://www.cdc.gov/EID/content/16/11/1671.htm
- Ryerson AB, Peters ES, Coughlin SS, Chen VW, Gillison ML, Reichman ME, Wu X, Chaturvedi AK, Kawaoka K. Burden of potentially human papillomavirus-
associated cancers of the oropharynx and oral cavity in the US, 1998-2003. Int J of Cancer. 2008 Nov 15;113(10 Suppl):2901-9.
- D'Souza G, Agrawal Y, Halpern J, Bodison S, Gillison ML. Oral sexual behaviors associated with prevalent oral human papillomavirus infection. J
Infect Dis. 2009 May 1;199(9):1263-9.
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