Melanoma Cancer Stages / Staging

For patients who haven’t been staged, one of the first things your doctors at Cancer Treatment Centers of America (CTCA) will determine is the stage of your melanoma. This information is crucial to developing your individualized treatment plan.

Melanoma cancer stages are assigned based on the size or thickness of the tumor, whether or not it has spread to the lymph nodes or other organs, and certain other characteristics, such as growth rate.

TNM Staging

The American Joint Commission on Cancer has developed a uniform staging system that allows doctors to determine how advanced a melanoma is, and to share that information with each other in a meaningful way. This melanoma cancer staging system, known as TNM staging, is composed of three key pieces of information:

• Tumor (T) describes the tumor’s thickness, or how deep it has grown into the skin. The thickness of the melanoma, also known as the Breslow measurement, is an important factor in predicting whether or not a tumor has spread. The thicker the melanoma, the greater the chance of it spreading. The rate at which the tumor cells are dividing (also known as the mitotic rate), and the presence or absence of ulceration (an open, bleeding sore), are also considered in determining the T category.
• Nodes (N) indicates whether or not the melanoma cancer has spread to nearby lymph nodes, or the channels connecting the lymph nodes.
• Metastasis (M) refers to whether the melanoma has spread to distant organs, as well as on levels of LDH, a substance in the blood.

Melanoma may be staged before surgery (clinical staging), based on physical exam and imaging results. It will also be staged after surgery (pathologic staging), in which the clinical information will be combined with information gained from biopsies. Because it uses more information, pathologic cancer staging is the most accurate.

Melanoma Stage Grouping

After the TNM staging components have been scored, your CTCA team will determine the overall stage of your melanoma:

• Stage 0 - The cancer cells are confined to the epidermis (the top layer of the skin) and have not spread. At this stage, the cancer is usually handled by surgery alone.
• Stage I – The cancer cells have grown deeper into the skin, but have not spread to the lymph nodes or other parts of the body.
  • Stage IA – The cancer is very small, less than 1 mm deep, and does not appear ulcerated. It is also not dividing rapidly.
  • Stage IB – This melanoma cancer is either very small, less than 1 mm deep, but it is ulcerated or dividing more rapidly, OR the cancer is between 1-2 mm deep without any sign of ulceration.
• Stage II - Melanomas at this stage have grown deeper into the skin, or have more high-risk features, but have not spread to the lymph nodes or beyond. 
  • Stage IIA – The cancer cells have grown 1-2 mm deep into the skin, and the tumor appears ulcerated, OR the cancer is 2-4 mm deep but is not ulcerated. 
  • Stage IIB – The cancer is 2-4 mm thick with ulceration, OR thicker than 4 mm but not ulcerated.
  • Stage IIC – The cancer is more than 4 mm thick, and it is ulcerated.
• Stage III – The melanoma cancer cells have spread to nearby lymph nodes, but not to distant organs.
  • Stage IIIA – The cancer can be any size, without ulceration, but a small number of cancer cells which can only be seen under a microscope have been found in 1-3 nearby lymph nodes.
  • Stage IIIB – Melanomas at this stage can be any size but they are either ulcerated with cancer cells in 1-3 lymph nodes that can only be seen under a microscope OR they are not ulcerated but there are enough cancer cells in 1-3 nearby lymph nodes to make them visibly enlarged OR cancer cells can be found in nearby areas of the skin or lymphatic channels, but not in the lymph nodes.
  • Stage IIIC – Melanomas at this stage can be any thickness. If it is ulcerated, either 1-3 nearby lymph nodes are enlarged OR cancer cells can be found in the nearby skin or lymphatic channels. Other cancers at this stage may or may not be ulcerated, but cancer cells can be found in 4 or more nearby lymph nodes.
• Stage IV – The cancer cells have spread beyond the skin and regional lymph nodes to distant organs such as the liver, lungs or brain, or distant lymph nodes and areas of the skin. Your evaluation, as well as your medical history and other relevant factors will be carefully reviewed by your care team at CTCA to develop a customized melanoma treatment plan for you.

Your evaluation, as well as your medical history and other relevant factors will be carefully reviewed by your care team at CTCA to develop a customized melanoma treatment plan for you.

Next Topic: Melanoma Treatment