What Are the Risk Factors for Anal Cancer
A risk factor is anything that increases a person’s chance of getting a disease such as cancer. Different cancers have different risk factors. For example, exposing skin to strong sunlight is a risk factor for skin cancer. Smoking is a risk factor for cancers of the lung, mouth, larynx, bladder, kidney, colon, anus, and several other organs. But having a risk factor, or even several, does not mean that a person will get the disease.
Human papillomavirus: Most doctors feel that squamous cell anal cancer is caused by the human papillomavirus (HPV), the same virus thought to be responsible for cervical cancer. There are several types of the virus but the one most likely to cause this cancer is called HPV-16. This virus is most often transmitted by sexual contact and more likely to be found in people who have had many sex partners.
One sign of infection by this virus is genital warts sometimes called condylomas. These are caused by HPV.
Sexual activity: Having multiple sexual partners is a risk factor for women. Another risk factor is anal intercourse for both men and women, particularly under the age of 30.
Smoking: Smoking also increases the risk of anal cancer. Current smokers are about 4 times more likely to have cancer of the anus compared with people who do not smoke. Quitting smoking will reduce the risk. People who used to smoke but have quit are only slightly more likely to develop this cancer compared with nonsmokers.
Lowered immunity/HIV infection: Higher rates of the disease occur among people with reduced immunity, such as organ transplant patients who must take medications that suppress their immune system. Another important risk factor is infection with the human immunodeficiency virus (HIV), the virus that causes AIDS.