What is HPV?

HPV is actually 100 related viruses. Each represents a different type of HPV. Some of them cause warts or papillomas, which are non-cancerous tumors. HPV viruses live in the moist cells (called squamous epithelial cells) that line the organs and cavities in our body that open to the outside, such as the mouth and anus. HPV viruses are divided into two groups: high risk and low risk. High-risk viruses are more likely to lead to cancer.

Genital HPV is actually very common in men and women. Four out of five women will probably be infected by HPV by the time they turn 50. Often the virus does not produce any noticeable symptoms and most people never know they're infected.

You contract HPV through direct genital contact during vaginal, oral and anal sex. There's no cure for HPV, but doctors can treat HPV lesions if they appear. Fortunately, our immune system gets rid of 90 percent of these viruses within two years of infection, even the high-risk variety. For the remaining 10 percent, however, HPV can lead to cancer.

What other types of cancers does HPV cause?

Other types of HPV-related cancers are rare but they do occur. HPV can cause anal, vulvar, vaginal and penile cancers as well as some head and neck cancers. The likelihood of developing any of these cancers varies among different ethnic groups.

HPV causes 90 percent of the estimated 2,500 annual anal cancer cases in the U.S. (1,600 in women, 900 in men). White women and black men are more likely to develop anal cancer. White women are also more likely to develop vulvar cancer, but more black and Hispanic women develop vaginal cancer from the HPV. The incidence of both cancers is very small. Penile cancer, also uncommon, is more prevalent among Hispanics.

Oral HPV infection is a strong risk factor for oropharyngeal cancer, or cancer of the middle of the throat, which includes the soft palate, base of the tongue and the tonsils.

Risk factors for HPV infection

HPV is transmitted sexually. Common risk factors include:

  • Many sex partners
  • Being younger than 25
  • Beginning sexual intercourse at 16 or younger
  • Having a sexual partner who's had many partners

Currently there is no vaccine for any other HPV-related cancers.