A risk factor is anything that increases a person’s chance of developing cancer. Some risk factors can be controlled, such as smoking, and some cannot be controlled, such as age and family history. Although risk factors can 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 communicating them to 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’s sarcoma:

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

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

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

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

Sexual activity. Homosexual men have a higher risk of HHV-8, as well as HIV. For more information.

While it is not possible to completely prevent Kaposi’s sarcoma, a person can significantly reduce his or her risk by avoiding the known risk factors, especially avoiding risky sexual practices and the use of contaminated intravenous (IV) needles that raises the risk of HIV/AIDS infection.