Stages and types of melanoma
Some doctors call in situ cancers pre cancer. In a way, they are. Although the cells are cancerous, they cannot spread to other parts of the body, so in situ cancers are not a cancer in the true sense. But if they are not treated, in situ cancers can develop into .
Melanoma skin cancer starts in cells called melanocytes. Melanoma in situ means the cancer cells are all contained in the epidermis where they started. They have not grown deeper into the skin.
Stage 0 is part of the number staging system. This goes from stage 0 to stage 4. It tells you how thick the melanoma is and if the cancer cells have spread to the or other parts of your body. Your doctor might also use the TNM staging system for melanoma skin cancer.
Doctors also use another staging system for melanoma called the TNM staging system. It stands for Tumour, Node, Metastasis.
T describes the size of the tumour
N describes whether there are any cancer cells in the lymph nodes
M describes whether the cancer has spread to a different part of the body
The TNM staging system describes the cancer in detail. The number staging system puts these details together to give an overall stage. This can be easier to understand.
In the TNM staging system melanoma in situ is the same as Tis, N0, M0.
Read about TNM staging for melanoma skin cancer
The stage of the cancer helps your doctor decide what treatment you need. Treatment also depends on:
where the melanoma is
your general health and level of fitness
Surgery is the main treatment for melanoma in situ. After your diagnosis, you usually have an operation to remove 0.5cm or more of healthy tissue around where the melanoma was. This is called a .
If your doctor is sure they have removed enough tissue, this is all the treatment you need.
Read more about surgery to remove melanoma
Surgery can cause scarring and some people may not be well enough to have an operation. Instead of surgery, you might have treatment with a cream called imiquimod. You put imiquimod on the affected area, over a number of weeks. Your doctor, nurse or pharmacist will tell you how long to use it for.
You might have another skin biopsy after you have had imiquimod treatment to see if it has worked.
Read more about imiquimod cream
Last reviewed: 02 Jan 2025
Next review due: 02 Jan 2028
If you have symptoms of melanoma skin cancer you should see your GP. They might ask you to have some tests and may refer you to a specialist.
The stage of a melanoma skin cancer tells you how deeply it has grown down into the skin. It also tells you if it has spread elsewhere in your body and how far.
Treatments include surgery, cancer drugs and sometimes radiotherapy. Which ones you have depends on the melanoma stage, where on your body it is and your general health.
Coping with melanoma skin cancer can be difficult. You might find it helpful to talk about your feelings. And there are people who can support you and your family.
Survival for melanoma skin cancer depends on many factors including the stage of the cancer when it was diagnosed, the treatment you have and your general health.
Melanoma develops in cells called melanocytes. You have these in your skin and other parts of your body. Melanoma that starts in the skin is called melanoma skin cancer.
About Cancer generously supported by Dangoor Education since 2010. Learn more about Dangoor Education
Search our clinical trials database for all cancer trials and studies recruiting in the UK.
Meet and chat to other cancer people affected by cancer.
Questions about cancer? Call freephone 0808 800 40 40 from 9 to 5 - Monday to Friday. Alternatively, you can email us.
