How is the disease diagnosed?

If a melanoma is suspected, a biopsy will be done. The entire lesion will be removed along with extra tissue around it. If the growth is too large to remove entirely, a sample will be taken. The lesion must be carefully examined under a microscope to determine if it is a melanoma.

If melanoma is found, additional tests or surgery may be ordered to determine the extent, or stage, of the disease. These tests may include:

Nearby lymph nodes may be removed for examination under a microscope. A new procedure, called sentinel lymph node biopsy, may eventually help to reduce the number of lymph nodes that need to be removed for study. Dye is injected near the tumor area. The lymph node to which the dye flows first is called the sentinel node. The sentinel node or nodes are the areas to which the cancer was likely to spread first. If the sentinel node has no cancer, the remaining lymph nodes may be left in place.