Melanoma Skin Cancer

Key Points for This Section

* Melanoma is a disease in which malignant (cancer) cells form in the skin cells called melanocytes (cells that color the skin).
* Melanoma can occur anywhere on the body.
* Unusual moles, exposure to sunlight, and health history can affect the risk of developing melanoma.
* Possible signs of melanoma include a change in the appearance of a mole or pigmented area.
* Tests that examine the skin are used to detect (find) and diagnose melanoma.
* Certain factors affect prognosis (chance of recovery) and treatment options.

Melanoma is a disease in which malignant (cancer) cells form in the skin cells called melanocytes (cells that color the skin).

Melanocytes are found throughout the lower part of the epidermis. They produce melanin, the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes produce more pigment, causing the skin to tan, or darken.

The skin is the body’s largest organ. It protects against heat, sunlight, injury, and infection. The skin has 2 main layers: the epidermis (upper or outer layer) and the dermis (lower or inner layer).

When melanoma starts in the skin, the disease is called cutaneous melanoma. This summary is about cutaneous (skin) melanoma. Melanoma may also occur in the eye and is called intraocular or ocular melanoma. (Refer to the summary on Intraocular (Eye) Melanoma Treatment for more information.)

There are 3 types of skin cancer:

* Melanoma.
* Basal cell skin cancer.
* Squamous cell skin cancer.

Melanoma is more aggressive than basal cell skin cancer or squamous cell skin cancer. (Refer to the summary on Skin Cancer Treatment for more information on basal cell and squamous cell skin cancer.)

Melanoma can occur anywhere on the body.

In men, melanoma is often found on the trunk (the area from the shoulders to the hips) or the head and neck. In women, melanoma often develops on the arms and legs. Melanoma usually occurs in adults, but it is sometimes found in children and adolescents.

Unusual moles, exposure to sunlight, and health history can affect the risk of developing melanoma.

Risk factors include the following:

* Unusual moles.
* Exposure to natural sunlight.
* Exposure to artificial ultraviolet light (tanning booth).
* Family or personal history of melanoma.
* Being white and older than 20 years.
* Red or blond hair.
* White or light-colored skin and freckles.
* Blue eyes.

Possible signs of melanoma include a change in the appearance of a mole or pigmented area.

These and other symptoms may be caused by melanoma or by other conditions. A doctor should be consulted if any of the following problems occur:

* A mole that:
o changes in size, shape, or color.
o has irregular edges or borders.
o is more than 1 color.
o is asymmetrical (if the mole is divided in half, the 2 halves are different in size or shape).
o itches.
o oozes, bleeds, or is ulcerated (a hole forms in the skin when the top layer of cells breaks down and the underlying tissue shows through).
* Change in pigmented (colored) skin.
* Satellite moles (new moles that grow near an existing mole).

Tests that examine the skin are used to detect (find) and diagnose melanoma.

If a mole or pigmented area of the skin changes or looks abnormal, the following tests and procedures can help detect and diagnose melanoma:

* Skin examination: A doctor or nurse examines the skin to look for moles, birthmarks, or other pigmented areas that look abnormal in color, size, shape, or texture.
* Biopsy: A local excision is done to remove as much of the suspicious mole or lesion as possible. A pathologist then looks at the tissue under a microscope to check for cancer cells. Because melanoma can be hard to diagnose, patients should consider having their biopsy sample checked by a second pathologist.

Suspicious areas should not be shaved off or cauterized (destroyed with a hot instrument, an electrical current, or a caustic substance).

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

* The stage of melanoma (whether cancer is found in the outer layer of skin only, or has spread to the lymph nodes, or to other places in the body.
* Whether there was bleeding or ulceration at the primary site.
* The location and size of the tumour.
* The patient’s general health.

Although many people are successfully treated, melanoma can recur (come back).

Stages of Melanoma

Key Points for This Section

* 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 following stages are used for melanoma:
o Stage 0
o Stage I
o Stage II
o Stage III
o Stage IV

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.

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

* Wide local excision: A surgical procedure to remove some of the normal tissue surrounding the area where melanoma was found, to check for cancer cells.
* Lymph node mapping and sentinel lymph node biopsy: Procedures in which a radioactive substance and/or blue dye is injected near the tumour. The substance or dye flows through lymph ducts to the sentinel node or nodes (the first lymph node or nodes where cancer cells are likely to have spread). The surgeon removes only the nodes with the radioactive substance or dye. A pathologist then checks the sentinel lymph nodes for cancer cells. If no cancer cells are detected, it may not be necessary to remove additional nodes.
* Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
* CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerised tomography, or computerised axial tomography. For melanoma, pictures may be taken of the chest, abdomen, and pelvis.
* MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
* PET scan (positron emission tomography scan): A procedure to find malignant tumour cells in the body. A small amount of radionuclide glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumour cells show up brighter in the picture because they are more active and take up more glucose than normal cells.
* Laboratory tests: Medical procedures that test samples of tissue, blood, urine, or other substances in the body. These tests help to diagnose disease, plan and check treatment, or monitor the disease over time.

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

The following stages are used for melanoma:

Stage 0

In stage 0, melanoma is found only in the epidermis (outer layer of the skin). Stage 0 is also called melanoma in situ.

Stage I

Stage I is divided into stages IA and IB.

* Stage IA: In stage IA, the tumour is not more than 1 millimeter thick, with no ulceration. The tumour is in the epidermis and upper layer of the dermis.
* Stage IB: In stage IB, the tumour is either:
o not more than 1 millimeter thick, with ulceration, and may have spread into the dermis or the tissues below the skin; or
o 1 to 2 millimeters thick, with no ulceration.

Stage II

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

* Stage IIA: In stage IIA, the tumour is either:
o 1 to 2 millimeters thick, with ulceration; or
o 2 to 4 millimeters thick, with no ulceration.
* Stage IIB: In stage IIB, the tumour is either:
o 2 to 4 millimeters thick, with ulceration; or
o more than 4 millimeters thick, with no ulceration.
* Stage IIC: In stage IIC, the tumour is more than 4 millimeters thick, with ulceration.

Stage III

In stage III, the tumour may be any thickness, with or without ulceration, and:

* has spread to 1 or more lymph nodes; or
* has spread into the nearby lymph system but not into nearby lymph nodes; or
* has spread to lymph nodes that are matted (not moveable); or
* satellite tumours (additional tumour growths within 2 centimeters of the original tumour) are present and nearby lymph nodes are involved.

Stage IV

In stage IV, the tumour may be any thickness, with or without ulceration, may have spread to 1 or more nearby lymph nodes, and has spread to other places in the body.

Recurrent Melanoma

Recurrent melanoma is cancer that has recurred (come back) after it has been treated. The cancer may come back in the original site or in other parts of the body, such as the lungs or liver.

Treatment Option Overview

Key Points for This Section

* There are different types of treatment for patients with melanoma.
* Four types of standard treatment are used:
o Surgery
o Chemotherapy
o Radiation therapy
o Biologic therapy
* Other types of treatment are being tested in clinical trials. These include the following:
o Chemoimmunotherapy

There are different types of treatment for patients with melanoma.

Different types of treatment are available for patients with melanoma. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. Before starting treatment, patients may want to think about taking part in a clinical trial. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment.

Clinical trials are taking place in many parts of the country. Information about ongoing clinical trials is available from the NCI Web site. Choosing the most appropriate cancer treatment is a decision that ideally involves the patient, family, and health care team.

Four types of standard treatment are used:

Surgery

Surgery to remove the tumour is the primary treatment of all stages of melanoma. The doctor may remove the tumour using the following operations:

* Local excision: Taking out the melanoma and some of the normal tissue around it.
* Wide local excision with or without removal of lymph nodes.
* Lymphadenectomy: A surgical procedure in which the lymph nodes are removed and examined to see whether they contain cancer.
* Sentinel lymph node biopsy: The removal of the sentinel lymph node (the first lymph node the cancer is likely to spread to from the tumour) during surgery. A radioactive substance and/or blue dye is injected near the tumour. The substance or dye flows through the lymph ducts to the lymph nodes. The first lymph node to receive the substance or dye is removed for biopsy. A pathologist views the tissue under a microscope to look for cancer cells. If cancer cells are not found, it may not be necessary to remove more lymph nodes.

Skin grafting (taking skin from another part of the body to replace the skin that is removed) may be done to cover the wound caused by surgery.

Even if the doctor removes all the melanoma that can be seen at the time of the operation, some patients may be offered chemotherapy after surgery to kill any cancer cells that are left. Chemotherapy given after surgery, to increase the chances of a cure, is called adjuvant therapy.

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy).

In treating melanoma, chemotherapy drugs may be given as a hyperthermic isolated limb perfusion. This technique sends anticancer drugs directly to the arm or leg in which the cancer is located. The flow of blood to and from the limb is temporarily stopped with a tourniquet, and a warm solution containing anticancer drugs is put directly into the blood of the limb. This allows the patient to receive a high dose of drugs in the area where the cancer occurred.

The way the chemotherapy is given depends on the type and stage of the cancer being treated.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.

Biologic therapy

Biologic therapy is a treatment that uses the patient’s immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body’s natural defenses against cancer. This type of cancer treatment is also called biotherapy or immunotherapy.

Other types of treatment are being tested in clinical trials. These include the following:

Chemoimmunotherapy

Chemoimmunotherapy is the use of anticancer drugs combined with biologic therapy to boost the immune system to kill cancer cells.

Treatment Options by Stage

Stage 0 Melanoma

Treatment of stage 0 melanoma is usually surgery to remove the tumour and a small amount of normal tissue around it.
Stage I Melanoma

Treatment of stage I melanoma may include the following:

* Surgery to remove the tumour and some of the normal tissue around it.
* A clinical trial of surgery to remove the tumour and some of the normal tissue around it, with or without lymph node mapping and selective lymphadenectomy.
* A clinical trial of new techniques to detect cancer cells in the lymph nodes.
* A clinical trial of lymphadenectomy with or without adjuvant therapy.

Stage II Melanoma

Treatment of stage II melanoma may include the following:

* Surgery to remove the tumour and some of the normal tissue around it, followed by removal of nearby lymph nodes.
* Lymph node mapping and sentinel lymph node biopsy, followed by surgery to remove the tumour and some of the normal tissue around it. If cancer is found in the sentinel lymph node, a second surgical procedure can be performed to remove additional nearby lymph nodes.
* Surgery followed by high-dose biologic therapy.
* A clinical trial of adjuvant chemotherapy and/or biologic therapy, or immunotherapy.
* A clinical trial of new techniques to detect cancer cells in the lymph nodes.

Stage III Melanoma

Treatment of stage III melanoma may include the following:

* Surgery to remove the tumour and some of the normal tissue around it.
* Surgery to remove the tumour with skin grafting to cover the wound caused by surgery.
* Surgery followed by biologic therapy.
* A clinical trial of surgery followed by chemotherapy and/or biologic therapy.
* A clinical trial of biologic therapy.
* A clinical trial comparing surgery alone to surgery with biologic therapy.
* A clinical trial of chemoimmunotherapy or biologic therapy.
* A clinical trial of hyperthermic isolated limb perfusion using chemotherapy and biologic therapy.
* A clinical trial of biologic therapy and radiation therapy.

Stage IV Melanoma

Treatment of stage IV melanoma may include the following:

* Surgery or radiation therapy as palliative therapy to relieve symptoms and improve quality of life.
* Chemotherapy and/or biologic therapy.
* A clinical trial of new chemotherapy and/or biologic therapy, or vaccine therapy.
* A clinical trial of radiation therapy as palliative therapy to relieve symptoms and improve quality of life.
* A clinical trial of surgery to remove all known cancer.

Treatment Options for Recurrent Melanoma

Treatment of recurrent melanoma may include the following:

* Surgery to remove the tumour.
* Radiation therapy as palliative therapy to relieve symptoms and improve quality of life.
* Palliative treatment with biologic therapy.
* Hyperthermic isolated limb perfusion.
* A clinical trial of biologic therapy and/or chemotherapy as palliative therapy to relieve symptoms and improve quality of life.