Melanoma skin cancer
The number staging system goes from stage 0 to stage 4. Stage 0 melanoma is also called melanoma in situ.
Your doctor might also use the Breslow thickness to describe how deeply the melanoma has grown into your skin.
Melanoma starts in cells called melanocytes. You have these in your skin and other parts of your body including your eye. There are different types of melanoma skin cancer.
The TNM stage is a way of describing how thick the melanoma is and if it has spread. TNM stands for Tumour, Node, Metastasis.
The Breslow thickness describes how deeply the melanoma has gone into the skin. Doctors use this to work out the Tumour (T) stage of the melanoma.
Melanoma in situ is also called stage 0 melanoma. It means the cancer cells are contained in the top layer of skin and have not spread.
Stage 1 means the melanoma is only in the skin. There is no sign that it has spread to lymph nodes or other parts of the body.
Stage 2 melanoma is only in the skin. There is no sign that it has spread to nearby lymph nodes or other parts of the body.
Stage 3 means the melanoma has spread to nearby lymph nodes. Or it has spread to an area between the melanoma and the nearby lymph nodes.
Stage 4 melanoma skin cancer has spread to other parts of the body. It is also called advanced melanoma skin cancer.
Last reviewed: 21 Jan 2025
Next review due: 21 Jan 2028

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