Surgery for Melanoma Skin Cancer

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

Wide excision

When melanoma is diagnosed by skin biopsy, more surgery will probably be needed to help make sure the cancer has been removed (excised) completely. This fairly minor operation will cure most thin melanomas.

Local anesthesia is injected into the area to numb it before the excision. The site of the tumor is then cut out, along with a small amount of normal skin around the edges (called the margin). The wound is usually stitched back together afterward. This will leave a scar.

The removed sample is then viewed with a microscope to make sure that no cancer cells were left behind at the edges of the skin that was removed.

Wide 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 need larger margins (both at the edges and in the depth of the excision).

The margins can also vary based on where the melanoma is on the body and other factors. For example, if the melanoma is on the face, the margins may be smaller to avoid large scars or other problems. Smaller margins might increase the risk of the cancer coming back, so be sure to discuss the options with your doctor.

Mohs surgery

In some situations, Mohs surgery (also known as Mohs micrographic surgery, or MMS) might be an option. This type of surgery is used more often for some other types of skin cancer, but not all doctors agree on using it for melanoma.

Mohs surgery is done by a specially trained dermatologist or surgeon. In this procedure, the skin (including the melanoma) is removed in very thin layers. Each layer is then looked at with a microscope. If cancer cells are seen, the doctor removes another layer of skin. This is repeated until a layer shows no signs of cancer. This is a slow process, often taking several hours, but it means that more normal skin near the tumor can be saved, which can help the area look better after surgery.

Amputation

In uncommon situations where the melanoma is on a finger or toe and has grown deeply, part or all of that digit might need to be amputated.

Lymph node dissection

In this operation, the surgeon removes all of the lymph nodes in the region near the primary melanoma tumor. For example, if the melanoma is 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 near the melanoma. Depending on the thickness and location of the melanoma, this may be done by physical exam, or by imaging tests (such as ultrasound or CT or PET scans) to look at nodes that are not near the body surface.

If the nearby lymph nodes are abnormally hard or large, and a fine needle aspiration (FNA) 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 Tests for Melanoma Skin Cancer for a description of this procedure.) If the sentinel lymph node does not contain cancer, then there is no need for a lymph node dissection because it’s unlikely the melanoma has spread to the lymph nodes. 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.

It’s 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 life 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 can be 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. 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. For more information, see Lymphedema.

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

Surgery for metastatic melanoma

If melanoma has spread (metastasized) from the skin to other organs such as the lungs or brain, the cancer is very unlikely to be curable by surgery. Even when only 1 or 2 areas of spread are found by imaging tests such as CT or MRI scans, there are likely to be others 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 removed completely, this surgery may help some people live longer. Removing metastases in some places, such as the brain, might also help prevent or relieve symptoms and improve a person’s quality of life.

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

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Mitchell TC, Karakousis G, Schuchter L. Chapter 66: Melanoma. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff’s Clinical Oncology. 6th ed. Philadelphia, Pa: Elsevier; 2020.

National Comprehensive Cancer Network (NCCN). Practice Guidelines in Oncology: Cutaneous Melanoma. Version 2.2019. Accessed at https://www.nccn.org/professionals/physician_gls/pdf/cutaneous_melanoma.pdfon June 11, 2019.

Ribas A, Read P, Slingluff CL. Chapter 92: Cutaneous Melanoma. In: DeVita VT, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 11th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2019.

Swetter SM, Tsao H, Bichakjian CK, et al. Guidelines of care for the management of primary cutaneous melanoma. J Am Acad Dermatol. 2019;80:208-250.

Last Medical Review: August 14, 2019 Last Revised: August 14, 2019

American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.