If you have been diagnosed with melanoma, your doctor will need to know the stage, or extent that the disease has spread in order to plan the best treatment.
In stage 0, the melanoma cells are found only in the outer layer of skin cells and have not invaded deeper tissues.
The tumor is no more than 1 millimeter thick.
The tumor is no more than 1 millimeter thick with the outer layer (epidermis) of skin appearing scraped under the microscope. (This is called ulceration).
The tumor is at least 1-2 millimeters thick with ulceration or 2-4 millimeters thick without ulceration.
The tumor is 2-4 millimeters thick with ulceration or 4 millimeters thick without ulceration.
The tumor is more than 4 millimeters thick with ulceration.
The melanoma cells have spread to one or more nearby lymph nodes. Or, the melanoma cells have spread to tissues just outside the original tumor but not to any lymph nodes.
The melanoma cells have spread to other organs, to lymph nodes, or to skin areas far away from the original tumor.
Updated March 24, 2015