In stage 0, the melanoma cells are found only in the outer layer of skin cells and have not invaded deeper tissues.
Melanoma in stage I is thin:
- The tumor is no more than 1 millimeter (1/25 inch) thick. The outer layer(epidermis) of skin may appear scraped. (This is called an ulceration.
- Or, the tumor is between 1 and 2 millimeters (1/12 inch) thick. There is no ulceration. The melanoma cells have not spread to nearby lymph nodes.
The tumor is at least 1 millimeter thick:
- The tumor is between 1 and 2 millimeters thick. There is ulceration.
- Or, the thickness of the tumor is more than 2 millimeters. There may be ulceration. The melanoma cells have not spread to nearby lymph nodes.
The melanoma cells have spread to nearby tissues:
- 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.
Recurrent disease means that the cancer has come back (recurred) after it has been treated. It may have come back in the original site or in another part of the body.