Chemotherapy for Kaposi Sarcoma

Chemotherapy (chemo) is the use of drugs to treat cancer. When the drugs are given into a vein or by mouth, they enter the bloodstream to reach almost all areas of the body. This is a type of systemic treatment. It is useful to treat cancer that has spread to many areas of the body. When the drugs are injected directly into a tumor it is called intralesional chemotherapy. (See  Local Therapy for Kaposi Sarcoma.)

The systemic chemo drugs used most often to treat Kaposi sarcoma (KS) belong to a group known as liposomal anthracyclines. Anthracyclines are drugs that treat many different cancers. In liposomal anthracyclines, the drugs are enclosed in tiny fat globules. In this form, they are better taken up by tumors and have fewer side effects. The liposomal anthracyclines used in the US to treat KS are:

• Liposomal doxorubicin (Doxil^®)
• Liposomal daunorubicin (DaunoXome^®)

Another chemo drug commonly used to treat KS is paclitaxel (Taxol®). Initial studies show it seems to work as well as liposomal doxorubicin and its main side effect is a low white blood cell count.

Other chemotherapy drugs that treat KS include:

• Nab-paclitaxel (Abraxane®)
• Gemcitabine (Gemzar^®)
• Vinorelbine (Navelbine^®)
• Bleomycin
• Vinblastine (Velban^®)
• Vincristine (Oncovin^®)
• Etoposide (VP-16)

More than half of KS patients treated with chemo will improve, but KS generally doesn’t go away completely. Sometimes chemo can be stopped as long as lesions are not causing problems or increasing in size and number. If the KS starts to get worse, treatment may be restarted.

It can be hard to give chemo to people for long periods of time if they have immune system problems (such as HIV/AIDS), because chemo drugs can also weaken the immune system. In all patients, it is important to try to improve immune function and treat related infections. This is especially important when giving chemo.

As previously noted, patients with epidemic KS should be treated with combined antiretroviral therapy (cART), which can be given along with systemic chemotherapy.

When choosing a treatment plan, your doctor will take into account drug interactions between the antiretroviral drugs and the chemo drugs. Once there is adequate control of the KS disease, chemo may be stopped, at least for a time. The KS may then be controlled with cART alone.

Chemo drugs attack cells that are dividing quickly, which is why they work against cancer cells. But other cells in the body, such as those in the bone marrow, the lining of the mouth and intestines, and the hair follicles, also divide quickly. These cells are also likely to be affected by chemotherapy, which can lead to side effects such as:

• Nausea and vomiting
• Loss of appetite
• Mouth sores
• Diarrhea
• Hair loss
• Increased risk of infection (from too few white blood cells)
• Easy bruising or bleeding (from too few blood platelets)
• Fatigue (from too few red blood cells)

The side effects of chemo depend on the type of drug, the amount taken, and the length of treatment.

Some drugs can have other side effects. For example, drugs such as vincristine or paclitaxel can damage nerves (called neuropathy), sometimes leading to numbness, tingling, or pain, particularly in your fingers and toes. This can also cause some weakness in your arms and legs. These problems tend to be worse in AIDS patients because the AIDS virus affects bone marrow and often nerve cells.

Most side effects go away once treatment is finished, but some can last a long time (or even be permanent). Be sure to ask your doctor about the possible side effects from the chemo drugs that you will receive.

There are often ways to prevent or lessen these side effects. For example, drugs can be given to help nausea and vomiting. Tell your medical team about any side effects or changes you notice while getting chemo so that they can be treated promptly.