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Staging and prognosis of melanoma


The test results will help your doctors assign a stage to describe the melanoma. You may also have some other diagnostic tests, including blood tests and imaging tests (ultrasound, CT scan or PET scan), to work out whether the melanoma has spread from the primary site to other parts of the body. Staging the melanoma helps your health care team recommend the most appropriate treatment for you.

stage 0 (in situ)The melanoma is confined to the top, outer layer of the skin.
stage IThe melanoma has not moved beyond the primary site and is 2 mm or less in thickness (may or may not have ulceration).
stage IIThe melanoma has not moved beyond the primary site and is greater than 1 mm and ulcerated or greater than 2 mm in thickness (may or may not have ulceration).
stage IIIThe melanoma has spread to lymph nodes near the primary site, to nearby skin or tissues under the skin (subcutaneous).
stage IVThe melanoma has spread to distant skin and/or other parts of the body such as the lungs, liver, brain, bone or distant lymph nodes.

Stages 0, I and II are called early melanoma, while stage III is referred to as regional melanoma. Stage IV melanoma has spread to other parts of the body and is called advanced or metastatic.


Prognosis means the predicted outcome of a disease. You may wish to discuss your prognosis and treatment options with your doctor, but it is not possible for any doctor to predict the exact course of the disease. Instead, your doctor can discuss any concerns you have.

Melanoma can be treated most effectively in its early stages when it is still confined to the top layer of the skin (epidermis). The deeper a melanoma penetrates into the lower layer of the skin (dermis), the greater the risk that it could spread to nearby lymph nodes or other organs. In recent years, clinical trials have led to new treatments that continue to improve the prognosis for people with melanoma that has spread from the primary site (advanced melanoma).