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Melanoma Treatment

Stages of Melanoma

After melanoma has been diagnosed, tests are done to find out if cancer cells have spread within the skin or to other parts of the body.

The process used to find out whether cancer has spread within the skin or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment. Talk with your doctor about what the stage of your cancer is.

The following tests and procedures may be used in the staging process:

The results of these tests are viewed together with the results of the tumor biopsy to determine the melanoma stage.

There are three ways that cancer spreads in the body.

The three ways that cancer spreads in the body are:

When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. For example, if breast cancer spreads to the bones, the cancer cells in the bones are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.

The method used to stage melanoma is based mainly on the thickness of the tumor and whether cancer has spread to lymph nodes or other parts of the body.

The staging system is based on the following:

The following stages are used for melanoma:

Stage 0 (Melanoma in Situ)


Stage 0 melanoma in situ. Abnormal melanocytes are in the epidermis (outer layer of the skin).
Stage 0 melanoma in situ. Abnormal melanocytes are in the epidermis (outer layer of the skin).

In stage 0, abnormal melanocytes are found in the epidermis. These abnormal melanocytes may become cancer and spread into nearby normal tissue. Stage 0 is also called melanoma in situ.


Millimeters (mm). A sharp pencil point is about 1 mm, a new crayon point is about 2 mm, and a new pencil eraser is about 5 mm.
Millimeters (mm). A sharp pencil point is about 1 mm, a new crayon point is about 2 mm, and a new pencil eraser is about 5 mm.

Stage I


Stage I melanoma. In stage IA, the tumor is not more than 1 millimeter thick, with no ulceration (break in the skin). In stage IB, the tumor is either not more than 1 millimeter thick, with ulceration, OR more than 1 but not more than 2 millimeters thick, with no ulceration. Skin thickness is different on different parts of the body.
Stage I melanoma. In stage IA, the tumor is not more than 1 millimeter thick, with no ulceration (break in the skin). In stage IB, the tumor is either not more than 1 millimeter thick, with ulceration, OR more than 1 but not more than 2 millimeters thick, with no ulceration. Skin thickness is different on different parts of the body.

In stage I, cancer has formed. Stage I is divided into stages IA and IB.

Stage II


Stage II melanoma. In stage IIA, the tumor is either more than 1 but not more than 2 millimeters thick, with ulceration (break in the skin), OR it is more than 2 but not more than 4 millimeters thick, with no ulceration. In stage IIB, the tumor is either more than 2 but not more than 4 millimeters thick, with ulceration, OR it is more than 4 millimeters thick, with no ulceration. In stage IIC, the tumor is more than 4 millimeters thick, with ulceration. Skin thickness is different on different parts of the body.
Stage II melanoma. In stage IIA, the tumor is either more than 1 but not more than 2 millimeters thick, with ulceration (break in the skin), OR it is more than 2 but not more than 4 millimeters thick, with no ulceration. In stage IIB, the tumor is either more than 2 but not more than 4 millimeters thick, with ulceration, OR it is more than 4 millimeters thick, with no ulceration. In stage IIC, the tumor is more than 4 millimeters thick, with ulceration. Skin thickness is different on different parts of the body.

Stage II is divided into stages IIA, IIB, and IIC.

Stage III


Stage III melanoma. The tumor may be any thickness, with or without ulceration (a break in the skin), and (a) cancer has spread to one or more lymph nodes; (b) lymph nodes with cancer may be joined together (matted); (c) cancer may be in a lymph vessel between the primary tumor and nearby lymph nodes; and/or (d) very small tumors may be found on or under the skin, not more than 2 centimeters away from the primary tumor.
Stage III melanoma. The tumor may be any thickness, with or without ulceration (a break in the skin), and (a) cancer has spread to one or more lymph nodes; (b) lymph nodes with cancer may be joined together (matted); (c) cancer may be in a lymph vessel between the primary tumor and nearby lymph nodes; and/or (d) very small tumors may be found on or under the skin, not more than 2 centimeters away from the primary tumor.

In stage III, the tumor may be any thickness, with or without ulceration. One or more of the following is true:

Stage IV


Stage IV melanoma. The tumor has spread to other parts of the body.
Stage IV melanoma. The tumor has spread to other parts of the body.

In stage IV, the cancer has spread to other places in the body, such as the lung, liver, brain, bone, soft tissue, or gastrointestinal (GI) tract. Cancer may also spread to places in the skin far away from where the cancer first started.