Screening and Prevention

Screening

Anal cancer can often be found early because it starts in a part of the digestive tract that your doctor can see and reach. One technique that doctors use to find anal cancer early is the digital rectal exam:

• Digital rectal exam (DRE) - The doctor inserts a gloved, lubricated finger into your anus to feel for unusual lumps or growths. If you are at increased risk for anal cancer, ask your doctor whether you should have more frequent DREs.

Recently, doctors have started testing people at high risk for sexually transmitted diseases for anal intraepithelial neoplasia (AIN), which is caused by the human papilloma virus (HPV) and can become cancerous.

• Anal dysplasia screening - This is a test to detect anal dysplasia (abnormal cells that are not cancerous) known as anal intraepithelial neoplasia (AIN), intraepithelial lesions (AIL), or high-grade squamous intraepithelial lesions (HSIL). This test is similar to a Pap smear for cervical cancer. The doctor swabs the lining of the anus and a pathologist (doctor who specializes in diagnosing disease) examines the cells that come off on the swab under the microscope.

Some experts recommend using this test to screen for AIL in certain high-risk groups, including:

• Men who have sex with men, regardless of HIV status
• Women who have had cervical cancer or vulvar cancer
• HIV-positive men and women
• Transplant recipients

Prevention

Anal cancer is a rare cancer, so the risk of developing this disease is quite low. However, by avoiding the factors that are known to be related to anal cancer, you can make your risk of developing anal cancer even lower. The best way to reduce the risk of getting anal cancer is to avoid certain sexual practices that increase your risk of getting infected with the human papilloma virus (HPV) or human immunodeficiency virus (HIV). Both these viruses are thought to be involved in anal cancer development.

• Avoid risky sexual practices - Avoid sexual activities that have a high risk of HPV and HIV infection. These include having many partners, anal sex, or unprotected sex. Recent research shows that condoms might not completely protect you from HPV. Condoms can, however, protect you against HIV, which many doctors think plays a role in causing anal cancer. 

The U.S. Food and Drug Administration (FDA) approved a new vaccine that protects people from infection with HPV-16 (the type of HPV that can cause anal cancer) and HPV-18.

• HPV vaccine - The HPV vaccine is currently recommended for young females before they become sexually active. Recent studies have shown that giving the HPV vaccine to women and girls at high risk of cervical cancer (which is also caused by HPV) reduces the risk that they will develop cervical cancer. It is likely that HPV vaccines could also reduce the risk of anal cancers. Although no studies have shown this yet, several studies are examining the role of HPV vaccines in preventing anal cancer.

Another step that could be helpful in preventing anal cancer is to avoid or stop smoking.

• Stop smoking - Smoking is a known risk factor for anal cancer. Quitting smoking can reduce the risk. People who used to smoke but have quit are only slightly more likely to develop anal cancer than people who never smoked.

This content has been reviewed and approved by Myo Thant, MD.