WHAT IS MELANOMA?

Melanoma is a tumor of melanocytes, the pigment-producing cells that give our skin its color. These cells are located all over the skin, but are more heavily concentrated in moles. When one of these cells becomes malignant it produces a tumor called a melanoma. A melanoma may appear in a mole that has been present for a long time or in parts of the skin which previously appeared normal.

What Causes Melanoma?

There is no known cause. It tends to occur more frequently in people who have fair complexions and who sunburn easily. It is related to sun exposure, but only indirectly.

Is Melanoma Contagious?

No. It cannot be transmitted by close physical contact. However, possibly because of genes or inherited skin coloring, children of patients with melanoma have a slightly higher risk of developing melanoma.

Is Melanoma A Skin Cancer?

Yes and no. It is a kind of skin cancer because it is derived from one of the cells of the skin. What most people mean by "skin cancer", however, is a common tumor called a basal cell carcinoma. They tend not to spread and are usually cured by simple treatments. Melanoma, on the other hand, is quite rare and may metastasize to other parts of the body. This is the reason patients with melanoma are referred to groups of physicians specializing in melanoma treatment.

How Does Melanoma Spread?

Before the melanoma is removed from the skin, some of the malignant cells can invade either the lymphatic vessels or the blood vessels in the area. The lymphatic vessels contain lymph fluid that drains to certain lymph node groups. Therefore, if the cells invade these vessels, the lymph fluid would carry them to the lymph nodes. There they could grow into a small tumor. If the cells invade the blood vessels, the blood might carry them to other parts of the body.

If Melanoma Spreads, Where Does It Usually Go?

The most likely place for melanoma to reappear is in the lymph nodes closest to the site of the primary tumor. If the primary melanoma was on the arm, these lymph nodes would be in the armpit. For a primary melanoma on the leg, the corresponding lymph nodes would be in the groin. For a tumor on the head, the lymph nodes would be in the neck on the same side. The lymph nodes for primary melanoma on the trunk may be the armpit or the groin.

What is Meant by the Stage of Melanoma?
A new staging system* for malignant melanoma was officially accepted in 2010 as follows:

Stage
I: Primary 1.0 mm or less with or without ulceration and with or without mitoses ≥1/mm², or primary 1.01 - 2.0 mm without ulceration, no lymph node or distant metastases

II: Primary 1.01 - 2.0 mm with ulceration, or primary > 2.01 mm with or without ulceration, no lymph node or distant metastases

III: Lymph node metastasis, or in-transit metastases/satellites, no distant metastases

IV: Distant metastases

*American Joint Committee on Cancer: AJCC Cancer Staging Manual, Seventh Edition.

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