Human papillomavirus (HPV) is the cause of most anal cancers. According to the CDC, each year an estimated 5,957 people are diagnosed with anal cancer caused by HPV. Certain high-risk types of HPV are the source of most anal cancers. Fortunately, there are a number of steps you can take to protect yourself against HPV-associated anal cancer.
What Types of HPV Cause Cancer?
About 91% of cancers are believed to be caused by HPV. One type known as HPV-16 is the most likely to cause anal cancer.
In addition, HPV-6 and HPV-11 cause most cases of anal warts. These warts don’t usually develop into cancer, but men and women who have had anal warts are more likely to get anal cancer.
You can get HPV from anal sex, but penetration doesn’t have to occur for the infection to be passed. The virus is spread through skin-to-skin contact with another person. It can also spread from one body part to another, so an anal HPV infection could develop as the result of a genital HPV infection that has spread.
Preventing Anal Cancer
One of the best ways to protect yourself against HPV-associated anal cancer is to get the HPV vaccine. This vaccine is recommended by the CDC for:
- Women through age 26
- Men through age 21
- Men who have sex with other men, transgender people, and people with weakened immune systems through age 26
Gardasil 9 is FDA-approved for men and women through age 45. The vaccine can’t protect you against any types of HPV to which you’ve already been exposed, but it may provide protection against other HPV types.
Practicing safer sex by using condoms also reduces your risk of getting anal cancer from an HPV infection.
Anal Cancer Risk
Certain people have a higher risk for anal cancer, including those who:
- Have had other cancers likely to be caused by HPV
- Are HIV-positive
- Have multiple sex partners
- Smoke cigarettes
If you’re in a group with a higher risk for anal cancer caused by HPV, talk to your doctor about getting routine anal cancer screenings. A doctor can perform a screening by swabbing the anal lining or using a scope to look inside the anal canal. These screenings can help with early detection of precancerous areas, which helps to prevent anal cancer.
Symptoms of Anal Cancer
Because HPV typically produces no symptoms, people can go for years without realizing they have it. If a high-risk HPV type persists, it could eventually lead to anal HPV cancer symptoms like:
- Bleeding from the anus
- Pain in the anal area
- Chronic anal itching
- Discharge from the anus
- A growth in the anal opening
- Changes in bowel habits or narrower stools
- Swollen lymph glands in the anal or groin area
These symptoms could be related to less serious issues, such as hemorrhoids, but it’s important to see a doctor if they occur.
- Risk Factors for Anal Cancer: American Cancer Society, 2017.
- How Many Cancers Are Linked with HPV Each Year?: Centers for Disease Control and Prevention, 2018.
- HPV Vaccine Recommendations: Centers for Disease Control and Prevention, 2016.
- FDA approves expanded use of Gardasil 9 to include individuals 27 through 45 years old: U.S. Food & Drug Administration, 2018.
- Anal Cancer: American Society of Colon and Rectal Surgeons.
- About HPV / HPV & Cancer: Anal Cancer Foundation.