Skin Cancer

Physicians diagnose the cancer and determine what kind it is by looking at a sample of the tumor under a microscope. This alone does not determine what treatment you need to have. Before treatment, your doctors must determine if or how much the melanoma has spread. This is called staging the cancer.

In melanoma, staging reflects how thick the tumor is and whether or not it has spread to other organs. This is very important because the treatment and the outlook for your recovery depend on the stage of the cancer. Early stage malignant melanoma can be cured. If the cancer has spread to other organs, it is rarely curable, once again highlighting the importance of early detection.

Once identified, a suspected lesion is biopsied. If it is found to be melanoma, it will be surgically removed, often with the surrounding lymph nodes. A number of diagnostic tests may be performed, including a PET scan and a sentinel node biopsy.

PET is the most useful test that you can have when doctors are staging or re-staging metastatic melanoma because it is more sensitive than a CT scan or any other type of test at seeing the small deposits of metastatic tumor.

How PET works: In cancer, cells begin to grow at a much faster rate, feeding on sugars like glucose. PET works by using a small amount of a radioactive drug called a tracer in combination with a compound such as glucose. Once you are injected with the tracer and glucose, the tracer travels through your body. It emits signals as it travels and eventually collects in the organs targeted for examination. If an area in an organ is cancerous, the signals will be stronger since more glucose will be absorbed in those areas.

In metastatic melanoma, if the lymph nodes or if a distant organ such as the liver has become involved, the tumor deposits will take up more of the radioactive glucose. The extent of the spread of disease is a critical factor in deciding the surgical or medical course of treatment. If there is any reason to suspect that the melanoma has spread to other parts of the body, the doctor may order a PET scan. In one whole-body picture, the PET scan can look throughout your whole body to see if there are any clumps of the cancer cells that have spread. The PET scan can make the difference in determining whether or not surgery should be done. After first showing the doctors where the cancer cells are, PET can also see if the chemotherapy and/or radiation therapy has been effective at killing the them.

Call the doctors at the PET centers nearest you if you have melanoma and would like to discuss your treatment options.