Content Map Terms

Skin Cancer, Melanoma

Topic Overview

What is melanoma?

Melanoma is a kind of skin cancer. It isn't as common as other types of skin cancer, but it is the most serious.

Melanoma usually looks like a flat mole with uneven edges and a shape that is not the same on both sides. It may be black, brown, or more than one colour. Most melanomas show up as a new spot or skin growth. But they can form in an existing mole or other mark on the skin.

Melanoma can affect your skin only, or it may spread to your organs and bones. As with other cancers, treatment for melanoma works best when the cancer is found early.

This topic is about melanoma that occurs in the skin. It doesn't cover melanoma that occurs in the eye or in any other part of the body besides the skin.

What causes melanoma?

You can get melanoma by spending too much time in the sun. Too much UV radiation from sun exposure causes normal skin cells to become abnormal. These abnormal cells quickly grow out of control and attack the tissues around them.

You are at higher risk for melanoma if you have fair skin, a family history of melanoma, or many abnormal, or atypical, moles. These moles may fade into the skin and have a flat part that is level with the skin. They may be smooth or slightly scaly, or they may look rough and "pebbly."

What are the symptoms?

You may not have any symptoms in the early stages of melanoma. Or a melanoma may be sore, or it may itch or bleed.

Any change in the shape, size, or colour of a mole may be a sign of melanoma.

Melanoma may look like a flat, brown or black mole that has uneven edges. Melanomas usually have an irregular or asymmetrical shape. This means that one half of the mole doesn't match the other half. They may be any size but are usually 6 mm (0.25 in.) or larger.

Melanomas can be found anywhere on your body. Most of the time, they are on the upper back in men and women and on the legs of women.

How is melanoma diagnosed?

Your doctor will check your skin to look for melanoma. If your doctor thinks that you have melanoma, he or she will remove a sample of tissue (biopsy) from the area around the melanoma. Another doctor, called a pathologist, will look at the tissue to check for cancer cells.

If your biopsy shows melanoma, you may need to have more tests to find out if it has spread to your lymph nodes.

How is it treated?

The most common treatment is surgery to remove the melanoma. That is all the treatment that you may need for early-stage melanomas that have not spread to other parts of your body.

Other treatments for melanoma include chemotherapy, radiation therapy, immunotherapy, and targeted therapy.

Can you prevent melanoma?

The best way to prevent all kinds of skin cancer, including melanoma, is to protect yourself whenever you are out in the sun.

  • Try to stay out of the sun during the middle of the day (from 11 a.m. to 3 p.m.).
  • Wear sun-protective clothes when you are outside, such as a hat that shades your face, a long-sleeved shirt, and long pants.
  • Use sunscreen every day. Your sunscreen should have an SPF of least 30. Look for a sunscreen that protects against both types of UV radiation in the sun's rays—UVA and UVB. When you are outdoors for long periods of time, reapply sunscreen every 2 hours.
  • Take extra care to protect your skin when you're near water, at higher elevations, or in tropical climates.
  • Avoid sunbathing and tanning salons.

Check your skin every month for odd marks, moles, or sores that will not heal. Check all of your skin, but pay extra attention to areas that get a lot of sun, such as your hands, arms, and back. Ask your doctor to check your skin during regular physical examinations or at least once a year.

Health Tools

Health Tools help you make wise health decisions or take action to improve your health.

Actionsets are designed to help people take an active role in managing a health condition.

Cause

Melanoma is most often caused by too much exposure to the sun's UV rays. Examples include:footnote 1

  • Having had blistering sunburns at any time of life.
  • Getting intense sun exposure every now and then.

Things that make getting melanoma more likely include your skin type, the colour of your hair, and the colour of your eyes.

Symptoms

You may not have any symptoms in the early stages of melanoma. Or a melanoma may be sore, or it may itch or bleed.

Most melanomas start as a new skin growth on unmarked skin. The growth may change colour, shape, or size. These types of changes are an early sign that the growth is melanoma. But melanoma can also develop in an existing mole or other mark on the skin. Or it may look like a bruise that isn't healing or show up as a brown or black streak under a fingernail or toenail.

Melanoma can grow anywhere on the body. It most often occurs on the upper back in men and women and on the legs in women. Less often, it can grow in other places, such as on the soles, palms, nail beds, or mucous membranes that line body cavities such as the mouth, the rectum, and the vagina.

On older people, the face is the most common place for melanoma to grow. And in older men, the most common sites are the neck, scalp, and ears.footnote 1

Signs of melanoma

The most important warning sign for melanoma is any change in size, shape, or colour of a mole or other skin growth, such as a birthmark. Watch for changes that occur over a period of weeks to a month. The ABCDE system tells you what changes to look for.

  • A is for asymmetry. One half of the mole or skin growth doesn't match the other half.
  • B is for border irregularity. The edges are ragged, notched, or blurred.
  • C is for colour. The colour is not the same throughout the mole.
  • D is for diameter. The mole or skin growth is larger than the size of a pencil eraser.
  • E is for evolution. There is a change in the size, shape, symptoms (such as itching or tenderness), surface (especially bleeding), or colour of a mole.

Melanoma in an existing mole

Signs of melanoma in an existing mole include changes in:

  • Elevation, such as thickening or raising of a previously flat mole.
  • Surface, such as scaling, erosion, oozing, bleeding, or crusting.
  • Surrounding skin, such as redness, swelling, or small new patches of colour around a larger lesion (satellite pigmentations).
  • Sensation, such as itching, tingling, burning, or pain.
  • Consistency, such as softening or small pieces that break off easily.

Many other skin conditions (such as seborrheic keratosis, warts, and basal cell cancer) have features similar to those of melanoma.

Signs of melanoma that has spread

Symptoms of melanoma that has spread (metastatic melanoma) may be vague. They include swollen lymph nodes, especially in the armpit or groin, and a colourless lump or thickening under the skin.

What Happens

Melanoma develops when normal pigment-producing skin cells called melanocytes become abnormal, grow uncontrollably, and invade surrounding tissues. Usually only one melanoma develops at a time. Melanomas can begin in an existing mole or other skin growth, but most start in unmarked skin.

When melanoma is found early, it can often be cured by surgery to remove it. But after melanoma spreads, it is harder to cure.

Experts talk about prognosis in terms of "5-year survival rates." The 5-year survival rate means the percentage of people who are still alive 5 years or longer after their cancer was discovered. Remember that these are only averages. Everyone's case is different, and these numbers don't necessarily show what will happen to you. The estimated 5-year survival rate for melanoma is:footnote 2

  • 98% if cancer is found early and treated before it has spread.
  • 62% if the cancer has spread to close-by tissue.
  • 15% if the cancer has spread farther away, such as to the liver, brain, or bones.

What Increases Your Risk

A risk factor for melanoma is something that increases your chance of getting this cancer. Having one or more of these risk factors can make it more likely that you will get melanoma. But it doesn't mean that you will definitely get it. And many people who get melanoma don't have any of these risk factors.

Risk factors for melanoma include:footnote 1

  • Too much exposure to the sun's UV rays. This includes:
    • Having had blistering sunburns at any time of life.
    • Getting intense sun exposure every now and then.
  • Fair skin that doesn't tan and tends to sunburn or freckle, along with blue or green eyes or red or blond hair.
  • Numerous moles and/or more than one atypical mole.
  • A large mole you have had since birth.
  • A personal or family history of melanoma.
  • Changes in your genes, like the change that causes a skin disease called Xeroderma pigmentosum.

When should you call your doctor?

Call your doctor now if you have any of these symptoms:

  • You have trouble breathing or swallowing.
  • You cough up or spit up blood.
  • You have blood in your vomit or stool (bowel movement).
  • Your urine or stool is black, and the blackness isn't caused by taking iron or Pepto-Bismol.

The most important warning sign for melanoma is a change in size, shape, or colour of a mole or other skin growth (such as a birthmark). Call your doctor if you have:

  • Any change in a mole, including size, shape, colour, soreness, or pain.
  • A bleeding mole.
  • A discoloured area under a fingernail or toenail not caused by an injury.
  • A general darkening of the skin unrelated to sun exposure.

If you have been diagnosed with cancer, be sure to follow your doctor's instructions about calling when you have problems, new symptoms, or symptoms that get worse.

Examinations and Tests

To check for melanoma and whether or not it has spread, your doctor may:

Other techniques may include total-body photography to look for changes in any mole and to watch for new moles appearing in normal skin. A series of photos of the suspicious lesions may be taken. Then the photos can be used as a baseline to compare with follow-up photos.

Finding skin cancer early

  • Do a skin self-examination once a month. Your partner or a close friend can help you check places that are hard to see, such as your scalp and back.
  • Have your doctor check any suspicious skin changes. Be sure you see your doctor at least once a year. You may need checkups more often if you have:
    • Familial atypical mole and melanoma (FAM-M) syndrome, which is an inherited tendency to develop melanoma. Your doctor may need to check you every 4 to 6 months.
    • Increased exposure to ultraviolet (UV) radiation because of your job, hobbies, or outdoor activities.
    • Abnormal moles called atypical moles. These moles aren't cancerous. But their presence is a warning of an inherited tendency to develop melanoma.

Treatment Overview

Melanoma may be cured if it's found and treated in its early stages when it affects only the skin. If melanoma has spread, it is much harder to treat.

How much and what type of treatment you need depends on the stage.

Treatment choices

Treatments for melanoma include:

  • Surgery. The entire melanoma is cut out, along with a border (margin) of normal-appearing skin.
  • Chemotherapy, which uses medicines to stop or slow the growth of cancer cells.
  • Immunotherapy, which uses medicines to help your body's immune system fight the cancer.
  • Targeted therapy with inhibitors. These are medicines that inhibit, or prevent, cancer cells from growing by blocking signals in the cell. Inhibitors are only given if a gene test shows that a person has certain gene changes (mutations).

Metastatic and recurrent melanoma

Melanoma can spread (metastasize) to other parts of the body, where it can cause tumours. When melanoma has spread and appears as a tumour in another part of the body, it sometimes can be successfully treated with surgery. But metastatic melanoma usually needs other treatments, too, such as chemotherapy, interferon, immunotherapy, or radiation therapy.

Metastatic melanoma and melanoma that can't be removed with surgery may be treated with inhibitors.

Melanoma can come back after treatment. This is called recurrent melanoma. All of the treatments mentioned above may be used for recurrent melanoma as well as:

  • Hyperthermic isolated limb perfusion. If the melanoma is on your arm or leg, chemotherapy medicine may be added to a warm solution and injected into the bloodstream of that arm or leg. The flow of blood to and from that limb is stopped for a short time so the medicine can go right to the tumour.
  • Medicines injected directly into the tumour.
  • Lasers to destroy the tumour.

If your melanoma can't be cured, your doctors will try to control symptoms, reduce complications, and keep you comfortable.

Your doctor may recommend that you join a clinical trial if one is available in your area. Clinical trials may offer the best treatment option for people who have metastatic cancer. Clinical trials study other treatments, such as combinations of chemotherapy, vaccines, and immunotherapies. They are also studying targeted therapy.

Regular follow-up appointments are important after you have been diagnosed with melanoma. Your doctor will set up a regular schedule of checkups that will happen less often as time goes on.

You can find more information about skin cancer online:

Your emotions

Finding out that you have cancer can change your life. You may feel like your world has turned upside down and you have lost all control. Talking with family, friends, or a counsellor can really help. Ask your doctor about support groups. Or call the Canadian Cancer Society (1-888-939-3333) or visit its website at www.cancer.ca for more information.

Hospice palliative care

Cancer treatment has two main goals: curing cancer and making your quality of life as good as possible. Hospice palliative care can improve your quality of life by helping you manage your symptoms. It can also help you with other concerns that you may have when you are living with a serious illness.

For some people who have advanced-stage cancer, a time comes when treatment to cure cancer no longer seems like a good choice. This can be because the side effects, time, and costs of treatment are greater than the promise of cure or relief. But this isn't the end of treatment. Hospice palliative care providers will work to help manage pain and other symptoms or side effects. They may help you decide what treatment you want or don't want. And they can help your loved ones understand how to support you.

It can be hard to decide when to stop treatment to prolong your life and shift the focus to end-of-life care. You and your doctor can decide when you may be ready for hospice palliative care.

To learn more about supportive care, see:

Prevention

To help prevent skin cancer:

  • Protect your skin. This includes staying out of the sun during the midday hours and using sunscreen.
  • Examine your skin regularly, and have your doctor check your skin during all other health examinations, or at least once a year.

Home Treatment

Home treatment can help you manage any side effects that your treatment might cause. If your doctor gives you instructions or medicines to treat these side effects, be sure to follow them. In general, healthy habits such as eating a balanced diet and getting enough sleep and exercise may help control your symptoms.


  • Home treatment for nausea or vomiting
     includes watching for and treating early signs of dehydration, such as having a dry mouth or feeling light-headed when you stand up. Eating smaller meals may help. So can a little bit of ginger candy or ginger tea.

  • Home treatment for diarrhea
     includes resting your stomach and watching for signs of dehydration. Check with your doctor before using any non-prescription medicines for your diarrhea.

  • Home treatment for constipation
     includes gentle exercise along with getting enough fluids and having a diet that is high in fruits, vegetables, and fibre. Check with your doctor before using a laxative for your constipation.

  • Home treatment for fatigue
     includes making sure you get extra rest. Let your symptoms be your guide. Fatigue is often worse at the end of treatment or just after treatment is completed.

  • Home treatment for sleep problems
     includes going to bed at the same time every night and getting exercise during the day.

  • Home treatment for pain
     includes using heat and cold packs.

Stress, hair loss, and body image

  • The diagnosis of melanoma and the need for treatment can be very stressful. You may be able to reduce your stress by expressing your feelings to others. Learning relaxation techniques may also help reduce your stress.
  • Hair loss can be emotionally distressing. Not all chemotherapy medicines cause hair loss. And some people have only mild thinning that is noticeable only to them. Talk to your doctor about whether hair loss is an expected side effect with the medicines you will receive.
  • Your feelings about your body may change following a diagnosis of melanoma and the need for treatment. Adapt to your body-image changes by talking openly about your concerns with your partner and discussing your feelings with your doctor. Your doctor may also be able to refer you to groups that can offer more support and information.

Having cancer can change your life in many ways. For help in managing these changes, see the topic Getting Support When You Have Cancer.

Medications

Medicines for melanoma include:

  • Immunotherapy medicines, such as ipilimumab and interleukin-2 (IL-2).
  • Chemotherapy medicines, such as dacarbazine and temozolomide.
  • Inhibitors, such as trametinib and vemurafenib.

Medicines used to treat melanoma may be given as an outpatient treatment. But sometimes people need a short hospital stay.

Medicines may be taken by mouth or injected into your bloodstream so they can travel throughout your body. If the melanoma is on an arm or a leg, chemotherapy medicines may be added to a warm solution that is injected into the bloodstream of that limb. The flow of blood to and from that limb is stopped for a short time so the medicine can go right to the tumour. This is called hyperthermic isolated limb perfusion.

The side effects of some of the melanoma medicines can be serious.

Surgery

Surgery is the most common treatment for melanoma. Lymph nodes may be removed at the same time to check them for cancer. Surgery also may be done to remove lymph nodes that have cancer or to remove melanoma that may have spread to other parts of the body.

Surgery choices

The most common types of surgery used to treat melanoma include:


  • Excision

    . This surgery takes out the melanoma and a little of the tissue around it.

  • Lymph node dissection (lymphadenectomy)

    . This is surgery to remove lymph nodes to see if they have cancer cells. Or this may be done to remove lymph nodes that are cancerous.

  • Sentinel lymph node biopsy

    . This surgery removes the first lymph node that the cancer may have spread to from the tumour. If this lymph node doesn't have any cancer cells, then you may not need to have more lymph nodes removed.

After removal of a melanoma, you may need a skin graft or other reconstructive surgery for cosmetic reasons or to restore function. This is most likely if the melanoma was large or was a late-stage tumour.

Other Treatment

Radiation treatment

Radiation treatment is the use of high-energy X-rays to kill cancer cells and shrink tumours. It isn't as effective in treating melanoma as it is in other cancers. But it may be used to reduce the risk of melanoma coming back. Or it may be used when melanoma has spread to other parts fo the body, such as the brain or bone.

Complementary treatments

People sometimes use complementary therapies along with medical treatment to help relieve symptoms and side effects of cancer treatments. Some of the complementary therapies that may be helpful include:

Mind-body treatments like the ones listed above may help you feel better. They can make it easier to cope with cancer treatments. They also may reduce chronic low back pain, joint pain, headaches, and pain from treatments.

Before you try a complementary therapy, talk to your doctor about the possible value and potential side effects. Let your doctor know if you are already using any such therapies. They are not meant to take the place of standard medical treatment.

References

Citations

  1. Bailey EC, et al. (2012). Cutaneous melanoma. In LA Goldman et al., eds., Fitzpatrick's Dermatology in General Medicine, 8th ed., vol. 1, pp. 1416–1444. New York: McGraw-Hill.
  2. American Cancer Society (2012). Cancer Facts and Figures 2012. Atlanta: American Cancer Society. Available online: http://www.cancer.org/Research/CancerFactsFigures/CancerFactsFigures/cancer-facts-figures-2012.

Credits

Current as of:
September 8, 2021

Author: Healthwise Staff
Medical Review:
Kathleen Romito MD - Family Medicine
Brian D. O'Brien MD - Internal Medicine
Adam Husney MD - Family Medicine
Amy McMichael MD - Dermatology