A risk factor [2] is anything that increases a person's chance of developing cancer. Although risk factors often influence the development of cancer, most do not directly cause cancer. Some people with several risk factors never develop cancer, while others with no known risk factors do. However, knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices.

The following factors can raise a person's risk of developing Kaposi sarcoma:

Ethnicity. People of Jewish or Mediterranean descent, as well as equatorial Africans, have a higher risk of developing Kaposi sarcoma.

Gender. Men have a higher risk of developing Kaposi sarcoma than women.

Human herpesvirus 8 (HHV-8). This virus may cause Kaposi sarcoma to develop. It is also called the Kaposi sarcoma herpesvirus (KSHV). Most people infected with HHV-8 do not get Kaposi sarcoma; the cancer appears most often when a person with HHV-8 also has a lowered immune system.

Immune deficiency. People with HIV/AIDS and people whose immune systems are suppressed because of organ transplantation have a higher risk of developing Kaposi sarcoma.

Sexual activity. Homosexual men have a higher risk of HHV-8, as well as HIV. Learn more about HIV/AIDS-related cancer [3].

While it is not possible to completely prevent Kaposi sarcoma, a person can significantly reduce his or her risk by avoiding the known risk factors that raises the risk of HIV/AIDS infection, especially by avoiding risky sexual practices, such as having unprotected sex and using intravenous (IV) needles that have been used by someone else.