HPV-Associated Diseases

HPV infections are responsible for nearly 26,000 new cancer cases each year in the United States. Of these, 18,000 occur in women and 8,000 occur in men (Figure 2).[1] (See How HPV Infections Cause Cancers for more information on the progression from HPV infection to cancer.) HPV also causes more than 300,000 cases of genital warts and approximately 820 cases of juvenile-onset RRP in the U.S. each year.[2,3]* The combined cost of HPV-associated cancers and other conditions is estimated to be $8 billion per year in the United States.† A large majority of cancers caused by HPV are brought about by one of two types: HPV16 or HPV18 (Table 2). Together, these types cause about 22,000 cases of cancer in the United States each year.

Cervical cancer is the most common cancer caused by HPV. Almost all cases of cervical cancer—which kills 4,000 U.S. women each year [4]—are caused by HPV infections. Although cervical cancer is the cancer most commonly associated with HPV, the virus plays a significant role in other anogenital cancers in both men and women. These include cancers of the vulva, vagina, and anus in women and cancers of the anus and penis in men.[1,5]

HPV-associated cancers of the oropharynx (the part of the throat just behind the mouth) are a growing problem in the United States and many other high-income countries.[6] The incidence of these cancers more than tripled in the U.S. between 1988 and 2004.[7] At this rate, the number of new oropharyngeal cancer cases caused by HPV likely will exceed the number of cervical cancer cases by 2020. This shift has important public health implications, in part because oropharyngeal cancers are four times more common among men than among women (Figure 2). Thus, efforts to prevent HPV-associated diseases must focus on both females and males.[6]

Figure 2

Sources: Centers for Disease Control and Prevention. Human papillomavirus-associated cancers—United States, 2004-2008. MMWR. 2012 Apr 20;61(15):258-61. Available from: http://www.ncbi.nlm.nih.gov/pubmed/22513527; Hoy T, Singhal PK, Willey VJ, Insinga RP. Assessing incidence and economic burden of genital warts with data from a US commercially insured population. Curr Med Res Opin. 2009;25(10):2343-51. Available from: http://www.ncbi.nlm.nih.gov/pubmed/19650749; Chesson HW, Ekwueme DU, Saraiya M, Watson M, Lowy DR, Markowitz LE. Estimates of the annual direct medical costs of the prevention and treatment of disease associated with human papillomavirus in the United States. Vaccine. 2012;30(42):6016-9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/22867718

How HPV Infections Cause Cancers

HPV infection of cervical cells initiates a series of molecular events that sometimes, but not always, results in invasive cancer. Although less research has been done on other HPV-associated cancers, the progression from infection to cancer appears to occur through analagous processes. Many HPV infections are cleared by the immune system. Some of these transient infections result in low-grade precancerous lesions consisting of a few abnormally sized and oddly shaped cells. Many of these lesions disappear within a few months with no treatment. In some cases, persistent HPV infection causes high-grade precancerous lesions. These precancerous lesions sometimes regress spontaneously or can be treated if detected. However, some will progress to invasive cancer. The interval between cervical HPV infection and invasive cancer is usually at least 20 years; however, precancerous lesions usually develop much earlier. Detection and treatment of precancerous lesions through screening has reduced cervical cancer incidence and mortality in the United States and other high-income countries over the past several decades. HPV vaccines have potential to further reduce the burden of this disease by preventing both precancerous lesions and invasive cancers.

Sources: Woodman CB, Collins SI, Young LS. The natural history of cervical HPV infection: unresolved issues. Nat Rev Cancer. 2007;7(1):11-22. Available from: http://www.ncbi.nlm.nih.gov/pubmed/17186016; Crow JM. HPV: the global burden. Nature Outlook. 2012;488(7413):S2-3. Available from: http://www.ncbi.nlm.nih.gov/pubmed/22932437

Modified from: Crow JM. HPV: the global burden. Nature Outlook. 2012;488(7413):S2-3. Available from: http://www.ncbi.nlm.nih.gov/pubmed/22932437

Back to Top

« Previous Next »

---