how to treat a melanoma?
For patients with Stages III and IV disease, surgery may be followed with adjuvant therapy. Ask your physician to explain the possibilities and grounds for selection of one treatment over the other.
A number of drugs that are active in fighting cancer cells are being used to treat melanoma, either one at a time or incombinations. Currently, Dacarbazine (DTIC), given by injection, is the only chemotherapy approved by the FDA. DTIC may be combined with carmustin (BCNU) and tamoxifen, or with cisplatin and vinblastine. Another drug, temozolomide, can be given orally. Unfortunately, to date, the response of melanomas to chemotherapy has been limited, but a great deal of research into new drugs and new approaches is being carried out.
Another class of drugs, based on a different principle, has come into use more recently. They are anti-angiogenic, which means that they prevent new blood vessels from forming. The reason this is important is that they cut off the blood supply that would otherwise nourish the cancer cells and enable them to grow. These drugs are still experimental and a good deal of research into improving and combining them with others is going on. Studies are underway with the anti-angiogenic drug, thalidomide, combined with the chemotherapeutic agent, temozolomide. Angiostatin and endostatin are two other drugs in this class that have shown some degree of activity against melanoma in preliminary studies.
The isolation-perfusion method is sometimes used as a palliative (pain-relieving) treatment when the melanoma is on an arm or leg. "Isolation" means that the chemotherapy is "perfused" (added to) the blood flowing through the affected limb, and no other part of the body.
Immunotherapy/Biochemotherapy
This is one of the most exciting and changing fields in medicine, based on drugs that act on the body's immune system. A number of newly-developed treatments are now being tested with some success. Among the immunotherapies, several types of experimental melanoma vaccines are now viewed as promising. Unlike the influenza vaccine, given when you are well to prevent disease, these are given to people who already have melanoma. Clinical trials of various types of vaccine are underway with patients whose disease is in Stages III and IV. The vaccines are intended to stimulate the immune system so that it reacts more strongly against a patient's melanoma cells, destroying the cancer or slowing the progression. These vaccines are not a part of routine treatment at this time, so patients with advanced melanomas may wish to discuss this possibility with their physicians.
Another type of immunotherapy (also known as biologic therapy) makes use of chemicals that occur naturally in the body. The one you are most likely to hear about is interferon-alpha. This is the only systemic drug with FDA approval, and it has been shown to improve five-year survival of Stage III patients. Tumor necrosis factor (tumor-killing) factor is another of these naturally occurring substances. Both of these — especially interferon-alpha — are produced by white cells (lymphocytes) when they come in contact with tumor cells, viruses or other harmful substances, and have been shown to kill a number of tumors, including melanomas. They have some anti-angiogenic properties as well. However, both drugs have significant side effects which can limit their use.
Lymphokines, which are chemicals occurring naturally in small quantities in the body, are being used for Stage IV patients. They may also be produced by white blood cells (lymphocytes) which have been specially stimulated by antigens, a basic part of the immune system, to make them better "killers" of malignant cells. The best known of these therapies uses the lymphokine, interleukin-2, with or without the addition of interferon alpha, which enters and attacks melanoma cells. However, interleukin-2 is associated with very significant side effects when given in high doses. This form of immunotherapy is still in the experimental stage.
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