Surgery for melanoma

Surgery is the main treatment option for most cases of melanoma, and usually cures early stage melanomas.

Simple excision

Thin melanomas can usually be completely cured by a fairly minor surgery called simple excision. The tumor is cut out, along with a small amount of normal non-cancerous skin at the edges. The normal, healthy skin around the edges of the cancer is referred to as the margin.

Simple excision differs from an excisional biopsy. The margins are wider because the diagnosis is already known. The recommended margins vary depending on the thickness of the tumor. Thicker tumors call for larger margins.

Local anesthesia is injected into the area to numb it before the excision. The wound is carefully stitched back together afterwards. This will leave a scar.

Re-excision (wide excision)

When a diagnosis of melanoma is made by biopsy, the site will probably need to be excised again. More skin will be cut away from the melanoma site, and the sample will be viewed under a microscope to make sure that no cancer cells remain in the skin. The size of the margin depends on the thickness of the tumor (see the table above).

If the melanoma is on the face, the margins may be smaller to avoid disfigurement. In some cases, the surgeon may use Mohs surgery (but doctors disagree on its use for melanoma). In this procedure, the skin (including the melanoma) is removed in very thin layers. Each layer is viewed under a microscope for signs of cancer. The operation continues until a layer shows no signs of cancer. In theory, this allows the surgeon to remove the cancer while saving as much of the surrounding skin tissue as possible.

Amputation

If the melanoma is on a finger or toe, the treatment may require amputation of all or part of that digit. At one time, some melanomas of the arms and legs were also treated by amputation, but this is no longer done.

Lymph node dissection

In this operation, the surgeon removes all of the lymph nodes in the region near the primary melanoma. (For example, if a skin melanoma is found on a leg, the surgeon would remove the nodes in the groin region on that side of the body, which is where melanoma cells would most likely travel to first.)

Once the diagnosis of melanoma is made from the skin biopsy, the doctor will examine the lymph nodes nearest the melanoma. Depending on the thickness and location of the melanoma, this may be done by physical exam, or by imaging tests for nodes that are not near the surface.

If the nearby lymph nodes feel abnormally hard or large, and a fine needle aspiration biopsy or excisional biopsy finds melanoma in a node or nodes, a lymph node dissection is usually done.

If the lymph nodes are not enlarged, a sentinel lymph node biopsy may be done, particularly if the melanoma is thicker than 1 mm. (See the section called "How is melanoma diagnosed?" for a description of this procedure.) If the sentinel lymph node does not show cancer, then it is unlikely the melanoma has spread to the lymph nodes and there is no need for a lymph node dissection. If the sentinel lymph node contains cancer cells, removing the remaining lymph nodes in that area with a lymph node dissection is usually advised. This is called a completion lymph node dissection.

In the past, a lymph node dissection was sometimes done to see if the melanoma had spread to the nodes. Today, a sentinel lymph node biopsy is done first because it is a less invasive surgery that is less likely to cause side effects such as lymphedema (see below). A lymph node dissection may then be done afterward if needed.

It is not clear if a lymph node dissection can cure melanomas that have spread to the nodes. This is still being studied. Still, some doctors feel it might prolong a patient's survival and at least avoid the pain that may be caused by cancer growing in these lymph nodes.

A full lymph node dissection can cause some long-term side effects. One of the most troublesome is called lymphedema. Lymph nodes in the groin or under the arm normally help drain fluid from the limbs. If they are removed, fluid may build up. This can cause limb swelling, which may or may not go away over time. If severe enough, it can cause skin problems and an increased risk of infections in the limb. Elastic stockings or compression sleeves can help some people with this condition. Sometimes special devices that squeeze the limbs are used and may be helpful. For more information, see our document called Understanding Lymphedema (for Cancers Other Than Breast Cancer).

Lymphedema, along with the pain from the surgery itself, is why lymph node dissection is not done unless the doctor thinks it is necessary. Sentinel lymph node biopsy, however, is unlikely to have this effect. It is important to discuss the possible risks of side effects with your doctor before having these procedures done.

Surgery for metastatic melanoma

If melanoma has spread from the skin to distant organs such as the lungs or brain, the cancer is very unlikely to be curable by surgery. Even when only 1 or 2 metastases are found by imaging tests such as CT or MRI scans, there are likely to be other areas of metastasis that are too small to be found by these scans.

Surgery is sometimes done in these circumstances, but the goal is usually to try to control the cancer rather than to cure it. If 1 or even a few metastases are present and can be completely removed, this surgery may help some patients live longer. Removing metastases in some places, such as the brain, might also relieve symptoms and help improve the patient's quality of life.

If you have metastatic melanoma and surgery is recommended as a treatment option, talk to your doctor and be sure you understand what the goal of the surgery would be, as well as its possible benefits and risks.