The epidermis is the outer layer of skin consisting of three types of cells. Melanocytes are one of these cell types, and they are located at the deepest part of the epidermis, according to the National Cancer Institute. Melanocytes make the skin pigment melanin that tans the skin in response to sunlight. Melanoma is a type of skin cancer in which malignant cells originate in the melanocytes.
Wide Local Excision
About half of the new cases of melanoma appear on the skin as an abnormal new mole, and the other half develop from an existing mole or freckle. Treatment for melanoma that is less than 1ml in thickness, classified as a stage 1 or thin melanoma, involves surgically removing the mole, according to Macmillan Cancer Support. After a pathologist confirms that melanoma is present in the mole, a surgeon may want to perform a wide local excision. In this procedure, about 1cm of apparently normal skin tissue is removed from around the perimeter of the excised mole. Patients will have a local anesthetic for this surgery, and it will be done on an outpatient basis. The purpose of wide local excision is to ensure that no malignant melanoma cells remain after removal of the mole.
Lymph Node Dissection and Adjuvant Treatment
According to Macmillan Cancer Support, a stage 2 melanoma is one in which the mole is more than 2ml in thickness; a stage 3 melanoma is a melanoma that has spread to one or more lymph nodes. The lymph nodes are located throughout the body and they are part of the immune system. After the patient has undergone surgery to remove the stage 2 or 3 mole, a doctor will perform a biopsy on the lymph node closest to the site of the mole. If melanoma cells are present, the patient will need to have a lymph node dissection. This operation removes all of the lymph nodes near the melanoma. The patient's doctor may then recommend adjuvant treatment with interferon in an attempt to prevent a recurrence of the melanoma. Interferon is an infection-fighting substance produced by the immune system and synthesized by biotechnology companies for use as a drug. Patients will receive interferon as an injection under the skin three times a week.
Chemotherapy
According to the American Cancer Society, a stage 4 melanoma poses difficult treatment challenges because it has metastasized to remote lymph nodes or to other parts of the body. Skin tumors, metastatic lymph node tumors, or cancer that has spread from the melanoma to internal organs may be removed by surgery, but this is not always possible.
If surgery is not an option, then chemotherapy with dacarbazine and temozolomide might be useful. Even if these drugs kill or shrink the metastatic cancers, however, the tumors will begin to grow again after only three to six months.
Doctors have also tried immunotherapy with interferon or interleukin-2 and found that patients' lives were extended in a limited number of cases.
Another approach to treatment of stage 4 melanoma and its metastatic cancers is called biochemotherapy. This combines chemotherapy with interferon, interleukin-2 or both, says the American Cancer Society. One treatment regimen involves the use of interferon and temozolomide to reduce the size of tumors, thereby providing patients a better quality of life.
