How is melanoma skin cancer staged?
The stage of a melanoma is a description of how widespread it is. The tests described in the “How is melanoma found?” section are used to help decide the stage of the melanoma. The stage is very important because it affects the treatment and the outlook for recovery.
Stages are labeled using 0 and the Roman numerals I through IV (1-4), often followed by letters. The lower the number, the less the cancer has spread. A higher number, such as stage IV (4), means a more advanced cancer. The stage is based mainly on 3 key pieces of information:
- How far the main tumor has grown within the skin and other factors (see below).
- Whether the cancer has spread to nearby lymph nodes.
- Whether the cancer has metastasized (spread) to distant organs.
After looking at your test results, the doctor will tell you the stage of your cancer. Be sure to ask your doctor to explain your stage in a way you understand. This will help you decide on the best treatment for you.
Important factors for early-stage melanomas
For melanomas that have not spread, certain factors affect a person’s outlook and are therefore part of the staging.
- The thickness of the melanoma is measured from the skin biopsy sample.
- The mitotic rate is the portion of melanoma cells that are in the process of dividing (making more cells).
- Ulceration is a breakdown of the skin over the melanoma.
Last Medical Review: 05/01/2015
Last Revised: 02/01/2016