Kaposi sarcoma commonly affects people with weakened immune systems, such as those with stage 3 HIV, also known as AIDS. However, taking antiretroviral drugs can reduce the risk of developing the cancer.

In the United States, the most common type of Kaposi sarcoma occurs in people with stage 3 HIV who are not taking antiretroviral therapy.

People living with stage 3 HIV are more vulnerable to cancer. People not taking antiretroviral therapy to prevent HIV from progressing can be immunocompromised.

Survival rates are generally higher when a doctor diagnoses cancer early. Despite early detection, cancer can also spread rapidly in people with untreated HIV. In the early days of the AIDS epidemic, it was a leading cause of death.

Read on to learn more about Kaposi sarcoma and HIV.

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Kaposi sarcoma is a type of cancer that mostly occurs in people with weakened immune systems. This includes people taking drugs that weaken the immune system and people living with HIV.

People with late stage HIV who have very weak immune systems can develop Kaposi sarcoma. The human herpesvirus-8 (HHV-8) causes Kaposi sarcoma in people with weakened immune systems.

HIV does not directly cause Kaposi sarcoma. However, late stage HIV can weaken the immune system, making a person more prone to infections and diseases.

A typical immune system fights tumors early so they do not become cancerous. However, a weaker immune system is less effective, allowing tumors to grow out of control.

This can lead to Kaposi sarcoma and a wide range of infections in people with HIV.

According to a 2021 paper, the worldwide prevalence of Kaposi sarcoma is very low, with a rate of 0.3 women and 0.5 men per 100,000 people.

However, the rate is much higher in sub-Saharan Africa, where it is the leading cause of cancer in men and the third-leading cause of cancer in women.

The prevalence of HHV-8 is also around 40% in this region compared to 2–4% in northern Europe, Southeast Asia, and the Caribbean.

This may be because HIV rates are higher in sub-Saharan Africa, and people have limited access to treatment.

HIV treatment is essential in preventing Kaposi sarcoma. About 30% of people with HIV who do not take antiretroviral drugs will develop the cancer.

Having late stage HIV is a significant risk factor for developing Kaposi sarcoma.

Among people who do not have access to or take antiretroviral treatments, the risk is significantly higher, with about 30% of this group developing it. Low CD4 levels are also a risk factor.

Because HHV-8 allows this cancer to develop, the risk is highest among people who are HHV-8-positive and also have HIV.

The outlook for people with Kaposi sarcoma is better when a doctor diagnoses it early. This means the cancer will have less of a chance to spread.

Although some people with Kaposi sarcoma go on to develop another cancer, in those who do not, their outlook is generally positive.

According to the American Cancer Society, the overall 5-year survival rate of Kaposi sarcoma is 74%.

It is recommended that people with HIV contact a doctor if they:

  • develop any new symptoms, especially any growths that could be cancer
  • are not currently taking antiretroviral medications
  • develop signs of an infection, such as a fever

Anyone can have HIV, so it is important to get tested, especially after potential exposure. In fact, data suggests that 13% of people with HIV do not know they have the virus.

Kaposi sarcoma is a cancer that primarily develops in people with weakened immune systems, especially people with HIV. Taking antiretroviral drugs can greatly reduce the risk.

Like most cancers, Kaposi sarcoma responds best to treatment before it spreads. To improve their outlook, people who develop any new health symptoms should contact a doctor, especially if they have late stage HIV.