Chemotherapy for melanoma skin cancer

Chemotherapy (chemo) uses drugs that kill cancer cells. The drugs are usually injected into a vein or taken by mouth as a pill. They travel through the bloodstream to all parts of the body and attack cancer cells that have already spread beyond the skin to lymph nodes and other organs. Because the drug reaches all areas of the body, it is called a systemic therapy.

Chemo is often used to treat advanced melanoma. Although it is usually not as effective in melanoma as it is in some other types of cancer, chemo may relieve symptoms or extend survival for some patients.

Doctors give chemotherapy in cycles, with each period of treatment followed by a rest period to allow the body time to recover. Each chemotherapy cycle typically lasts for a few weeks.

Several chemo drugs may be used to treat melanoma:

• Dacarbazine (also called DTIC)
• Temozolomide
• Paclitaxel
• Carmustine (also known as BCNU)
• Cisplatin
• Carboplatin
• Vinblastine

Dacarbazine, temozolomide, and paclitaxel may be given either alone or along with some of the other drugs on the list. It is not clear if using combinations of drugs is more helpful than using a single drug, but it can add to the side effects.

Some studies suggest that combining chemo drugs with immunotherapy drugs such as interferon-alpha and/or interleukin-2 (see “Immunotherapy for melanoma skin cancer”) may be more effective than a single chemo drug alone, although it's not clear if this helps people live longer. This type of treatment is also called biochemotherapy or chemoimmunotherapy.

Isolated limb perfusion: This is a type of chemotherapy sometimes used to treat advanced melanomas that are confined to an arm or leg. It is done during a surgical procedure. The blood flow of the arm or leg is separated from the rest of the body, and a high dose of chemotherapy is circulated through the limb for a short period of time.

To do this, a tube is placed into the artery that feeds blood into the limb, and a second tube is placed into the vein that drains blood from it. The tubes are connected to a special machine. A tourniquet is tied around the limb to make sure the chemotherapy does not enter the rest of the body. A high dose of chemotherapy (usually with a drug called melphalan) is then infused into the blood in the limb. During the session, the blood exits the limb through the tube in the vein, is heated by a machine in the operating room, and is then recirculated back into the limb through the tube in the artery. By the end of the treatment the drug is completely washed out of the limb, and the tubes are removed so that the circulation is returned to normal.

Isolated limb perfusion lets doctors give high doses to the area of the tumor without exposing internal organs to these doses, which would otherwise cause severe side effects.

Possible side effects of chemotherapy

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.

The side effects of chemotherapy depend on the type and dose of drugs given and the length of time they are taken. These side effects may include:

• Hair loss
• Mouth sores
• Loss of appetite
• Nausea and vomiting
• Diarrhea
• 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)

These side effects are usually short-term and go away once treatment is finished. Some drugs may have specific effects that are not listed above, so be sure to talk with your cancer care team about what you might expect in terms of side effects.

There are often ways to lessen side effects. For example, you can be given drugs to help prevent or reduce nausea and vomiting. Be sure to ask your doctor or nurse about drugs to help reduce side effects.

You should report any side effects you notice while getting chemo to your medical team so that they can be treated promptly. In some cases, the doses of the chemo drugs may need to be reduced or treatment may need to be delayed or stopped to prevent side effects from getting worse.