How is Melanoma Staged?
Melanoma stages are based on several factors. The thickness of the melanoma, whether it has spread to the lymph nodes, and how far it has spread within the body are all important.The system most often used to stage melanoma is the American Joint Committee on Cancer (AJCC)
- T describes the thickness of the melanoma.
- N describes how many lymph nodes are affected.
- M describes spread to distant organs of the body.
Each letter is assigned a numerical value and the results of this analysis are grouped into five stages (0, 1, 2, 3, and 4). Early melanoma is defined as stage 1 and stage 2 disease. Advanced melanoma is defined as stage 3 and stage 4 disease.
Stage 0 is also called melanoma in situ. This is the most frequently seen melanoma stage. The melanoma is limited to the epidermis. This means that the cancer cells are only in the outer layer of the skin and have not grown any deeper.
Stage 1 is a very early melanoma. Stage 1 is divided into two subcategories:
- Stage 1A describes a melanoma that is very thin (less than 1 mm), dividing slowly, and not ulcerated.
- Stage 1B describes a melanoma that is very thin (less than 1 mm in thickness) but dividing more quickly or ulcerated. It also includes melanomas that are a little thicker (less than 2 mm).
Depending on your situation, a sentinel lymph node biopsy may be suggested. Treatment of stage 1 includes a second surgery to remove a wider border of normal skin around the biopsy site.
In stage 2, the melanoma is thicker than 2mm. Stage 2 is divided into A, B, and C subcategories. A sentinel lymph node biopsy is usually suggested. Treatment of stage 2 includes a second surgery to remove a wider border of normal skin around the biopsy site. Surgery may be the only treatment required. The risk of recurrence, or return of the melanoma, or spread to another part of the body, is moderate in stage 2A. Some people, with larger tumours (stage 2B or 2C), have a higher risk of recurrence and may benefit from additional treatments.
Stage 3 is advanced melanoma. This stage is divided into A, B and C subcategories. Treatment of stage 3 may include a second surgery to remove lymph nodes in the area and a wider border of normal skin around the biopsy site. Possibility of additional treatment should be discussed with your oncologist. In recurrent melanoma, Stage 3 also includes in-transit disease where recurrence is 2cm or more from the original site.
Stage 4 is advanced melanoma. Cancer cells have spread to the lung or other organs, skin areas, or lymph nodes far away from the original growth. Melanoma commonly spreads to other parts of the skin, tissue under the skin, lymph nodes, and lungs. It can also spread to the liver, brain, bones, and other organs. Treatment of Stage 4 involves a discussion with your oncologist for available treatments and possibility of participating in clinical trials.