Once the type of melanoma has been established, the next step is to classify the disease as to its degree of severity.
Classifications for melanomas are called stages. The stage refers to the thickness, depth of penetration, and the degree to which the melanoma has spread. The staging is used to determine treatment.
Early melanomas (Stages I and II) are localized, and more advanced melanomas (Stages III and IV) have spread (metastasized) to other parts of the body. There are also subdivisions within stages.
Guide to Staging
New Melanoma Staging System – By means of an unprecedented cooperative effort among cancer centers around the world, the classification system recommended by the American Joint Commission on Cancer (AJCC) has been updated as of 2010. New findings about melanoma are incorporated to provide the most accurate diagnosis and prognosis (a forecast of how the disease is likely to progress).