Cancer starts when cells change and grow out of control. The changed (abnormal) cells often grow to form a lump or mass called a tumor. Cancer cells can also grow into (invade) nearby areas. And they can spread to other parts of the body. This is called metastasis.

Melanoma is a serious type of skin cancer. It starts in skin cells called melanocytes. These are cells that give skin its color. Melanoma is much less common than other types of skin cancer that start in other skin cells. But it's more likely to spread to other parts of the body.

Melanoma can happen anywhere on the skin. It's most often found in areas exposed to the sun. Male occurrence is usually between the shoulders and the hips or on the head or neck. Female occurrence is usually on the arms and lower legs. Sometimes melanoma starts in skin that's never exposed to sunlight, like the mouth, genitals, and anus. It may even start in the eye, under a fingernail or toenail, and in the nose and sinuses.

A risk factor is anything that may increase your chance of having a disease. The exact cause of someone's cancer may not be known. But risk factors can make it more likely for a person to have cancer. Some risk factors may not be in your control. But others may be things you can change.

The most common risk factors for melanoma include:

• Greater amount of time spent in the sun.
• Use of tanning booths or beds and sunlamps.
• Many moles or abnormal ones.
• Fair skin, blue eyes, freckles, or light hair.
• Family history of melanoma.
• Certain inherited gene changes and conditions, like xeroderma pigmentosum, Li-Fraumeni syndrome, and hereditary breast and ovarian cancer syndromes.
• Past history of skin cancer (any kind).
• Weakened immune system.

Talk with your doctor about your risk factors for melanoma and what you can do about them.

There is no sure way to prevent melanoma, but there are things you can do that may help lower your risk for it, such as:

• Wearing broad-spectrum sunscreen with SPF 30 or higher.
• Not using tanning booths or beds and sunlamps.
• Practicing sun safety. Limit time in the sun when UV light is strongest – between 10 a.m. and 4 p.m.
• Wearing sunglasses that have 100% UVA/UVB protection.
• Wearing clothing to shade your face and cover your body.
• Doing skin checkups often.

Regular skin self-exams may help you find skin cancer early, when it's smaller and easier to treat. Become familiar with the way your skin and moles look. Talk with your doctor about any changes, including bumps, spots, or other marks on your skin.

The first symptom of melanoma is often a change in a mole or the appearance of a new mole. The ABCDE rule can help you tell a normal mole from one that might be melanoma. The rule is:

• Asymmetry. One half of the mole does not match the other half.
• Border irregularity. The edges of the mole are ragged or irregular.
• Color. The mole has different colors in it. It may be tan, brown, black, red, or other colors. Or it may have areas that appear to have lost color.
• Diameter. The mole is bigger than 6 mm or ¼ inch across, about the size of a pencil eraser. But some melanomas can be smaller.
• Evolving. A mole changes in size, shape, or color.

Other symptoms that may be melanoma include:

• A mole that hurts, itches, or is sore.
• A mole that oozes, bleeds, or becomes crusty.
• A mole that looks different from your other moles.
• A sore that doesn't heal.
• A mole or sore that becomes red or swells at its edges or beyond.

Many of these may be caused by other health problems. Still, it's important to see a doctor if you have these symptoms. Only a doctor can tell if you have cancer.

If your doctor thinks you may have melanoma, you'll need certain exams and tests. You'll be asked about your health history, your symptoms, risk factors, and family history of disease. A physical exam and skin exam will be done. You may also have a biopsy.

A biopsy is the only way to confirm cancer. Tiny pieces of the changed mole or skin are removed and sent to a lab. Then they're tested for cancer cells. Ask you care team when you will get your results.

After a diagnosis of melanoma, you may need more tests. These help your doctors learn more about your overall health and the cancer. They're used to find out the stage of the cancer. The stage is how much cancer there is and how far it has spread (metastasized) in your body. It's one of the most important things to know when deciding how to treat the cancer.

After the stage of your cancer is known, your doctor will talk with you about what the stage means for your treatment. Be sure to ask your doctor to explain the details of your cancer.

Your treatment choices depend on the size, place, and stage of your melanoma. The goal of treatment may be to cure you, control the cancer, or help ease problems caused by cancer. Talk with your care team about your treatment choices, the goals of treatment, and what the risks and side effects may be. Other things to think about are if the cancer can be removed with surgery, how your body will look after treatment, and your overall health.

Types of treatment for cancer are either local or systemic. Local treatments remove, destroy, or control cancer cells in one area. Surgery and radiation are local treatments. Surgery is the most common way to treat melanoma. Systemic treatment is used to destroy or control cancer cells that may have traveled around your body. When taken by pill or injection, chemotherapy and targeted therapy are systemic treatments. You get just one treatment or a combination of treatments.

Melanoma may be treated with:

• Surgery.
• Radiation therapy.
• Chemotherapy.
• Immunotherapy.
• Targeted therapy.

Talk about your concerns with your doctor before making a decision.

Surgery to remove your melanoma will always result in a scar. Talk with your doctor about the size and type of scar you may have.

Cancer treatment, such as chemotherapy and radiation, can damage normal cells. This can cause side effects like hair loss, mouth sores, and vomiting.

Talk with your doctor about side effects linked with your treatment. There are often ways to manage them. There may be things you can do and medicines you can take to help prevent or control many treatment side effects.

Many people feel worried, depressed, and stressed when dealing with cancer. Getting treatment for cancer can be tough on the mind and body. Keep talking with your care team about any problems or concerns you may have. Work together to ease the effect of cancer and its symptoms on your daily life.

Here are tips:

• Talk with your family or friends.
• Ask your care team or social worker for help.
• Speak with a counselor.
• Talk with a spiritual advisor, such as a minister or rabbi.
• Ask your care team about medicines for depression or anxiety.
• Keep socially active.
• Join a cancer support group in person or online.

Cancer treatment is also hard on the body. To help yourself stay healthier, try to:

• Eat healthy foods, including as many protein foods as possible.
• Drink plenty of water, fruit juices, and other liquids.
• Keep physically active.
• Rest as much as needed.
• Talk with your care team about ways to manage treatment side effects.
• Take your medicines as directed by your team.

Your doctor will talk with you about when to contact them. You may be told to contact them if you have:

• New symptoms or symptoms that get worse.
• Signs of an infection, such as a fever.
• Side effects of treatment that affect your daily function or don't get better with treatment.

Ask your doctor what signs to watch for and when to contact them. Know how to get help after office hours and on weekends and holidays.

Tips to help you get the most from a visit to your doctor:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your doctor tells you.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you.
• Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your doctor if you have questions, especially after office hours or on weekends.