HPV and Oropharyngeal Cancer: Facts & Figures

HPV and oropharyngeal cancer FACTS
One of the most trending topics in the dental industry right now is the link between human papillomaviruses (HPV) and types of oropharyngeal cancer—predominantly in the young adult population. With so much new information being published on the topic, it can be difficult to keep up with it all and distinguish key findings that are applicable in clinical practice. For that reason, the list below represents the most recent facts and figures from evidence-based sources that support this oral-systemic connection:
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  • Human papillomaviruses (HPV) are a family of small viruses with a pronounced tropism for epithelial cells. More than 120 HPV types have been identified to date, and most code for between 8 and 10 proteins in their double-stranded circular DNA genome.
  • Collectively, the CDC reports that there are more than 40 types of HPV that can infect the genital areas and/or the mouth and throat.
  • There are both “low risk” types and “high risk” types of oral HPV; the low risk types may cause warts in the mouth or throat, while the high risk types are what may cause cancer in the head/neck—most commonly in the base of the tongue and tonsils (also referred to as “oropharynx”).
  • According to the CDC, approximately 7% of people in the U.S. have oral HPV, but only 1% have the type that is found in oropharyngeal cancers (HPV type 16).
  • More than 90% of all HPV-positive oropharyngeal cancers are associated with two specific types of HPV known as HPV-16 and HPV-18.
  • Overall, oral HPV is 3 times more common in men than in women; moreover, from 2005 to 2009, incidence rates of HPV-associated oropharyngeal cancer occurred in over 4 times more men than it did in women.
  • Between 2005 and 2009, incidence rates among men were highest in Caucasians and African-Americans (at 8.5 and 7.9 cases per 100,000 persons, respectively).
  • The CDC reported in 2012 that oropharyngeal cancer is the second most diagnosed of cancers associated with HPV.
  • By the year 2020, it has been estimated that the prevalence of HPV-positive oropharyngeal cancers in the U.S. could surpass the total number of HPV-related cervical cancers.
  • Each year, an average of 11,726 people are diagnosed with oropharyngeal cancer in the United States; of those cases, approx. 63% are associated with the oncogenic HPV infection.
  • A recent study presented at the American Society of Radiation Oncology annual meeting reported that the prevalence of cancer in the pharynx, tonsils, base of tongue, and soft palate (in adults ages 45 years and younger) increased by as much as 60% between 1973 and 2009.
  • A significant racial variance has been associated with this increase in prevalence as the number of cases among Caucasians grew 113% between 1973-2009, while it actually declined by 52% in African-Americans.
  • Regardless, the five-year survival rate for African-Americans with oropharyngeal cancer is still considerably worse than the survival rate in other races, but more research will be needed to identify why this is.
  • Between 2005 and 2009, incidence rates of HPV-associated oropharyngeal cancer increased 3.9% among Caucasian men and 1.7% among Caucasian women.
  • HPV infection increases the risk of oropharyngeal squamous cell cancer (OPSCC) independently of tobacco and alcohol use, according to the National Cancer Institute (NCI).
  • Between 1984 and 2004, the Journal of Clinical Oncology reported that the diagnosis rate of HPV-positive OPSCC increased by 225%, while the incidence rate of HPV-negative cancers declined by about 50%.
  • Cancer caused by HPV often takes years to develop after getting the HPV infection; unfortunately, many people experience no symptoms that they have ever been infected, so a diagnosis can be difficult to obtain.
  • If symptoms of oral HPV do occur, they are usually attributed to persistent sore throat, earaches, hoarse throat, enlarged lymph nodes, painful swallowing, and unexplained weight loss.
  • To date, there is currently no FDA-approved test to diagnose HPV in the mouth or throat.
  • It is undetermined whether or not HPV vaccines can prevent oropharyngeal cancers, but it is possible since the vaccines do prevent the initial infections that are associated with HPV types which eventually may develop into cancer.
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For more information on this topic, or to view the sources used in this article, please visit the following:
*Also, be sure to check out our NEW courseThe Link between HPV and Oropharyngeal Squamous Cell Carcinomas by Dr. John R. Basile DDS, DMSc

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