What is Melanoma?

Most moles and spots on the skin are harmless but it is important to look for any new, changing or unusual ones. Use the ABCDEs and the Ugly Duckling sign to help you.


People who have a higher risk of melanoma should check their skin regularly and get any suspicious looking spots checked by their doctor. This includes those who have fair skin that freckles easily, burns easily or tans poorly; and those with a history of melanomas or other types of skin cancer.

What is melanoma?

Melanoma is a type of skin cancer that starts in cells that make pigment (color) in the skin. It can occur anywhere on the body. It most often develops in areas that have been exposed to the sun, such as the back, legs, arms and face, but it can also form on the soles of the feet or palms of the hands, and in the genital area. Melanoma can also develop in places that don’t get much sun, such as the scalp and eyelids. These melanomas are called hidden melanomas and are more common in people with darker skin.

It’s not clear what causes melanoma. But UV radiation from the sun and from tanning beds is thought to play a role. This may cause DNA damage that leads to the formation of cancerous cells. These cells can then spread to other parts of the body through the blood, where they become a metastatic tumor.

The main risk factors for melanoma are being over 50, having fair skin that freckles or burns easily, and having many large or unusual moles. Having a history of multiple blistering sunburns as a child or teenager also increases the risk of getting melanoma. It’s important to have regular skin checks by a doctor, especially from early adulthood. If you notice any changes in a mole or other spot on the skin, tell your doctor right away.


Melanoma may first appear as a new spot on the skin or as a change in an existing mole. It can grow anywhere on the body, but it’s more likely to develop in sun-exposed areas, such as the face, ears and trunk of men, or the legs for women.

A new or changing mole should always be checked by a doctor, especially if it is itchy and bleeds easily. Often, these changes will be visible to the patient, but sometimes they can be less obvious. A changing or growing mole that is a different shape, size or color should also be evaluated by a doctor. Other symptoms of melanoma are blistering or bleeding, the presence of an unusual number of blood vessels near the lesion or an increased thickness of the tumor.

If a melanoma is found early, it can be treated with surgery. This can include wide local excision, with or without sentinel lymph node biopsy and elective node dissection, depending on the stage of the cancer.

You may also have tests to see if the melanoma has spread, such as a CT scan or an MRI. Other possible treatments include chemotherapy, which uses drugs to kill cancer cells and stop them from multiplying. It may be given by injection (intravenously) or in a tablet form.


The discovery of melanoma often comes as a surprise. It may be noticed by a patient, family member or friend; or a healthcare provider – such as a dermatologist during a skin exam; an ophthalmologist during an eye exam; or a general practitioner (GP) during a physical examination.

If a GP, nurse practitioner or physician assistant suspects melanoma, they will refer the patient to a dermatologist for further evaluation. This referral will usually include a history and physical exam and laboratory tests.

Most people with melanoma will need surgery to remove the tumor and surrounding tissue. This will depend on the thickness of the melanoma and whether it has spread (seen in the lymph nodes or other parts of the body).

Before surgery, your doctor will take a small sample of skin and tissue from the area where the melanoma is located. They will then look at this under a microscope. If they see cancer cells, they will remove more skin and tissue until they don’t find any more cancer cells. This is called a biopsy.

In some cases, a doctor may also feel the lymph nodes near the melanoma to see if they are enlarged. These are part of the body’s lymphatic system, a network of tissues and organs that helps fight infection and other diseases.


In early-stage melanoma, when it is confined to the top layers (epidermis) of skin and has not invaded deeper layers (dermis), surgery (wide local excision) is the main treatment. This is performed by a surgeon who carefully cuts out the growth, plus a small amount of healthy tissue around it. The goal is to remove the cancer and to prevent it from growing back at that site. Some scarring is a normal part of this procedure. If needed to close the wound, a skin flap or graft can be used.

If melanoma is found in later stages, or if it has spread to other parts of the body, treatment includes chemotherapy and radiation therapy. Chemotherapy uses anti-cancer medication to kill cancer cells and stop them from growing. It is usually given through a vein (intravenous treatment) but can also be taken by mouth.

A special type of surgery called Mohs surgery may be used to treat melanoma that has spread to the deeper layer of skin (dermis) or to other parts of the body. This technique has a very high success rate and can be used to help determine the extent of the melanoma.