Kaposi Sarcoma: Types, Symptoms, and Treatment

Kaposi sarcoma starts in the cells that line blood and lymph vessels. A Hungarian skin doctor, Moritz Kaposi, described it in 1872. Until the HIV epidemic, it stayed a rare tumor.

One fact shapes everything else. Under the microscope, the four forms look nearly the same. What differs is who gets it, how fast it moves, and what treatment fits. So naming the form is the first real step in care.

Nothing about this diagnosis is a judgment of anyone. It is a common virus meeting a weakened immune system.

Human herpesvirus 8, or HHV-8, is also called Kaposi sarcoma-associated herpesvirus. NCI's clinical summary states the finding plainly. HHV-8 turned up in biopsies from almost all patients, across all four forms. It was absent from tissue that was not involved.

Carrying the virus is not the same as getting the cancer. Most people who carry HHV-8 never develop it. Our page on HHV-8 covers the virus itself.

This form is rare. It affects men far more often. The ratio is roughly 10 to 15 men per woman. In North America and Europe, onset usually falls between ages 50 and 70. Most cases are in men of Italian or Eastern European Jewish ancestry.

It shows up as red, purple, or brown patches, plaques, or lumps. They do not hurt. The disease usually stays on one or both lower legs. The ankles and soles are the usual sites.

The course is slow. NCI calls it relatively benign and indolent. It can run 10 to 15 years or more. The first tumors grow slowly, and new ones appear over time. Two problems are common: venous stasis and lymphedema, which is fluid swelling in the affected leg.

Two later problems are worth naming. Lesions can form along the gut, in lymph nodes, and in other organs. These are usually silent. They are often found only at autopsy, though bleeding in the gut can happen. Second, as many as 33% of people with classic disease get a second primary cancer. It is most often non-Hodgkin lymphoma. That is why follow-up covers more than skin.

Endemic disease is diagnosed in sub-Saharan Africa. It usually affects children and younger adults who are HIV-negative. The category came from reports in the 1950s.

Before the AIDS epidemic, rates were highest in Uganda, Tanzania, Cameroon, and Congo. There the estimate passed 6 cases per 1,000 person-years. Why it happens is not settled. NCI lists three possible factors: saliva-sharing practices, chronic infection, and malnutrition.

Presentation splits by age. Adults look much like classic disease. In children it can be far more aggressive. That means widely swollen lymph nodes, heavy lymphedema, and spread to inner organs.

This form follows long-term immune suppression. An organ transplant is the usual reason. The size of the effect is striking. Solid-organ transplant recipients are 200 times more likely to get Kaposi sarcoma than the general population.

NCI lists four risk factors. They are male sex, older age, deeper immune suppression, and living where HHV-8 is common. Lesions usually appear on the skin in the first several months of therapy.

Treatment here is unusual, and it is good news. NCI says this form is generally managed well by lowering immune suppression. It usually needs no systemic treatment at all. Switching to an mTOR inhibitor such as sirolimus has helped in small studies.

Antiretroviral therapy changed this form. Many large cohorts show a steady, large drop in new cases since it came into use.

The picture today is not the one from the 1980s. NCI notes that most US cases now occur in people with high CD4 counts. Those people are already on antiretroviral therapy, with HIV fully suppressed.

Disease often moves in an orderly way. It starts with a few skin, mouth, or lymph node lesions. Then lesions become more numerous and widespread. It can reach the gut, lung, liver, and spleen. Most people with skin and mouth lesions feel well and have no body-wide symptoms. Sometimes lymph node or gut disease comes before any skin lesion.

No staging system for AIDS-associated disease is accepted everywhere. The AIDS Clinical Trials Group criteria are the ones in wide use. They score three things, each as good risk or poor risk:

• Tumor (T). Good risk means confined to skin, lymph nodes, or minimal oral disease on the palate. Poor risk means tumor-related swelling or ulceration, extensive oral disease, gut disease, or disease in other organs.
• Immune system (I). Good risk is a CD4 count of 200 cells per microliter or above. Poor risk is below 200.
• Systemic illness (S). Good risk means no history of opportunistic infections or thrush, no B symptoms, and a Karnofsky performance status of 70 or higher. B symptoms are unexplained fever, night sweats, involuntary weight loss over 10%, or diarrhea lasting more than two weeks.

An analysis of 294 patients tested all three. Each was tied to survival on its own. Immune damage was the strongest single predictor. That analysis also suggested a CD4 cutoff of 150 may sort groups better than the published 200.

For classic and endemic disease on the skin, NCI lists three equal options. They are radiation therapy, surgery, and local methods such as cryotherapy, laser, intralesional, or topical treatment. The radiation doses are specific. Low-voltage photon therapy uses 8 to 10 Gy in one dose, or 15 to 20 Gy over a week. Electron-beam therapy uses 4 Gy once a week for 6 to 8 weeks.

For AIDS-associated disease, treatment starts with the immune system. Most people with good-risk T0 disease see tumors shrink on antiretroviral therapy alone. Poor-risk T1 disease usually needs antiretroviral therapy plus chemotherapy. The chemotherapy is stopped once skin lesions clear.

Drug options, with the evidence NCI cites:

• Pegylated liposomal doxorubicin. In a multicenter trial of 55 patients with classic disease, the response rate was 71%, lasting a median of 25 months.
• Paclitaxel. In a randomized trial of 73 patients with AIDS-associated disease, response was 56% with paclitaxel and 46% with pegylated liposomal doxorubicin. Two-year survival was 79% and 78%.
• Pomalidomide. FDA-approved for Kaposi sarcoma with or without HIV. In a phase I/II study of 28 patients, overall response was 71%. It is teratogenic, prescribed through a REMS program, and given with aspirin to lower clot risk.
• Interferon alfa-2b. FDA-approved for AIDS-associated disease, with about a 40% response rate. Response is slow, with maximum effect after 6 months or more.

Local disease in AIDS-associated cases has more options. These include electrodesiccation and curettage, cryotherapy, surgical removal, radiation at 20 Gy or a little higher, intralesional vinblastine, and alitretinoin 0.1% gel.

For AIDS-associated disease, NCI states that no data show treatment improves survival. What treatment does do is real, though. It shrinks lesions. It eases the long-running swelling and ulcers on the legs. It controls symptoms from disease in the mouth or organs.

That is why the summary insists on close teamwork between cancer doctors and HIV specialists. Three things are called essential parts of care, not add-ons. They are antiretroviral treatment, prevention of opportunistic infections, and fast treatment of any new infection. For a broader view of virus-linked cancers, see our page on infections and cancer.

• Call your cancer team immediately, day or night, if you run a fever of 100.4 degrees Fahrenheit or higher at any point during chemotherapy such as pegylated liposomal doxorubicin or paclitaxel. CDC treats fever during chemotherapy as a medical emergency, because infection can turn life-threatening in hours. If you cannot reach them quickly, go to an emergency department and tell staff you are on chemotherapy.
• Call 911 or go to an emergency department if you have sudden breathlessness or cough up blood, which can mean disease in the lungs, or black or bloody stools or vomiting blood from gut lesions, or, on pomalidomide, one painful swollen leg or sudden chest pain.
• Call your care team the same day if a lesion breaks down, weeps or looks infected, if a leg becomes hot and tender, or if lesions flare soon after antiretroviral therapy starts, which can be immune reconstitution inflammatory syndrome.
• Call your care team within a day or two if mouth lesions make eating or swallowing harder, swelling in a limb is steadily worsening, or new lesions are appearing faster than before.

• Centers for Disease Control and Prevention, Fever During Chemotherapy, accessed August 13, 2026
• National Cancer Institute, Kaposi Sarcoma Treatment (PDQ) - Health Professional Version, updated May 7, 2025, accessed August 6, 2026
• National Cancer Institute, Kaposi Sarcoma Treatment (PDQ) - Patient Version, accessed August 6, 2026