The stage of a melanoma tells you how deeply it has grown into the skin, and how far it has spread. Doctors use different systems to stage melanoma. These include the TNM system or number staging system. Or they might use the Clark or Breslow scale to describe how deeply the melanoma has grown into your skin.
There are different types of melanoma. The different types are usually treated in the same way.
Tumour, node and metastasis (TNM) staging is one of the systems used to stage melanoma skin cancer.
The Clark scale and Breslow thickness describe how deeply the melanoma has gone into the skin.
Melanoma in situ is also called stage 0 melanoma. It means the cancer cells are contained in the top layer of skin.
Stage 1 melanoma is at an early stage. It's only in the skin and there's no sign that it has spread to lymph nodes or other parts of the body.
Stage 2 melanoma is only in the skin and there is no sign that it has spread to lymph nodes or other parts of the body.
Stage 3 generally means melanoma has spread to nearby lymph nodes. Or it's spread to an area between the melanoma and the nearby lymph nodes.
Stage 4 melanoma has spread elsewhere in the body, away from where it started (the primary site) and the nearby lymph nodes.