The treatment of melanoma may involve surgery, immunotherapy, targeted therapy, chemotherapy or radiotherapy, or a combination of several treatment techniques. Each of these treatments is outlined below.
The initial treatment of melanoma involves the surgical removal of the tumor in almost all cases. A local excision is made with a wide circumference around the affected area, removing all of the abnormal tissue and some of the surrounding normal tissue. Some patients may require a skin graft to cover the wound and promote skin healing if the area of removed tissue is particularly large.
The involvement of lymph nodes in the area is important and a biopsy is routinely conducted to monitor for the presence of abnormal cells at the same time as the surgery. A dye or radioactive substance is injected close to the tumor to demonstrate the movement through the lymph ducts and identify the duct most likely to be involved to take the biopsy. If there is evidence of cancer cells in the lymph nodes, they will need to be removed via lymphadenectomy and monitored for signs of abnormal cell growth.
Adjuvant therapy with chemotherapy or radiotherapy may be needed to reduce the risk of cancer recurrence.
Biologic or Immunotherapy
Biologic therapy, also known as immunotherapy, enhances the effect of the patient’s natural immune system to destroy abnormal cancerous cells. There are various types of this treatment for melanoma, including:
- Interferon: alters division of cancer cells to slow tumor growth
- Interleukin-2 (IL-2): boosts activity of immune cells such as lymphocytes to destroy cancer cells.
- Tumor necrosis factor (TNF) therapy: administration of natural protein made in the body to destroy cancer cells.
- Ipilimumab: a monoclonal antibody that boosts the immune response of the body to destroy cancer cells.
Targeted therapy uses drugs that direct their action to the quickly dividing cancer cells and cause less damage to normal cells than other treatment methods, such as chemotherapy or radiotherapy. There are several types of targeted therapy for melanoma, including:
- Signal transduction inhibitor therapy: blocks signaling between molecules inside cells that cause destruction of cancer cells. (e.g. vemurafenib, dabrafenib, trametinib)
- Monoclonal antibody therapy: antibodies produced in a laboratory for a single immune cell type that can identify substances that affect cancer cell growth and alter their function. (e.g. pembrolizumab)
- Oncolytic virus therapy: an emerging treatment involving an infective virus that breaks down cancer cells selectively.
- Angiogenesis inhibitors: an emerging treatment involving the obstruction of new blood vessels, preventing the flow of blood that is needed for tumor growth.
Chemotherapy is sometimes used in the treatment of melanoma, as an adjuvant therapy following surgical removal of the tumor. The cytotoxic medications stop the growth of cancer cells by inducing apoptosis or inhibiting their division.
Chemotherapy can be administered systemically via the mouth or intravenous injection to affect all cells throughout the body. It can also be administered regionally into the cerebrospinal fluid, an organ or body cavity for a more localized effect.
Radiation therapy uses high-energy x-rays and other radiation types to destroy or inhibit the growth of cancer cells.
External radiation therapy uses a machine external to the body to direct the radiation towards the location of the tumor and cancer cells. Internal radiation therapy uses a radioactive substance that is placed in or near the cancer, by way of a needle, seed, wire or catheter. External radiation therapy is used in the treatment of melanoma, as the tumors primarily affect the skin on the outside of the body.