Melanoma is the most common type of skin cancer. It appears as a coloured spot and can spread quickly if not treated early.
The most effective treatment is surgery to remove the melanoma and some of the surrounding skin (called a margin of safety). Some melanomas can be treated with chemotherapy and other medication.
Risk Factors
There are a number of risk factors that can increase your chances of developing Melanoma. The most common factor is sun exposure. This includes both natural sunlight and artificial UV radiation from sun lamps and tanning beds. It is important to avoid over-exposure to the sun and to use sunscreen with a high sun protection factor (SPF).
People with fair skin are more at risk for developing melanoma than people with darker complexions. This is because their skin has less of the pigment (color) that helps protect against harmful UV radiation. People with blond or red hair, light-colored eyes, and many freckles or moles are also at greater risk of getting melanoma. Although, melanoma can occur in people with dark complexions and in places of the body that do not get much sun exposure.
A family history of melanoma increases your risk of getting the disease. People with a close relative who has been diagnosed with melanoma have about a 2 to 3 times higher chance of developing the disease than people without a family history of the disease. It is recommended that people with a family history of melanoma should regularly have their skin examined by a health care professional.
Certain inherited conditions can increase your risk of developing melanoma, including xeroderma pigmentosum, retinoblastoma, and Li-Fraumeni syndrome. These diseases can affect your body’s ability to repair UV damage and can lead to increased growth of nevi (moles). Some medical treatments like chemotherapy, immunosuppressive drugs used after organ transplantation, and HIV infection can also increase your risk for melanoma by weakening your immune system.
Early Detection
Melanoma is more likely to be caught in its early stages when it is small and less likely to have spread. Because of this, it is very important to do regular self-exams and see a dermatologist regularly for professional skin exams (at least once a year).
If you notice a new spot or a change in the appearance of an existing mole, have it checked by your doctor right away. This is especially important if it has any of the following features:
A: Asymmetry: One side of the mole doesn’t match the other.
B: Border irregularity: Irregular or notched borders are characteristic of melanomas.
C: Color: A melanoma may have many colors, or an uneven distribution of color. It is also common for a melanoma to change in color over time.
E: Evolving: The mole is changing over time — it grows, gets darker or changes shape. Melanomas can evolve to become more dangerous.
The most effective way to reduce the risk of melanoma is to perform monthly self-exams of the entire body, including sun-exposed areas like the arms, legs, neck and head. It is also very important to get regular professional skin exams by a dermatologist, and to stick with the schedule your doctor recommends. Having a melanoma treated early significantly increases the chances of survival. It is also much cheaper to treat a melanoma in its early stage than to treat it later, when the tumor has grown deeper and spread.
Diagnosis
Melanoma is diagnosed by a physical exam and a medical history. A doctor will check the skin for moles, birthmarks and other pigmented areas that look abnormal in color, size, shape or texture. A sample of the abnormal mole or lesion may be taken (biopsied) and sent to a pathologist for evaluation. The results of this test will help determine if the tumor is cancerous and whether it has spread beyond the skin to other parts of the body.
A biopsy is a procedure during which your doctor removes all or part of the abnormal mole or lesion and a small amount of normal tissue around it. The tissue is then looked at under a microscope to check for cancer cells. Your doctor might also ask you to give a blood sample before the biopsy so that he or she can test your blood for certain gene changes that are associated with melanoma.
In addition, your doctor might do a procedure called lymph node mapping or sentinel lymph node biopsy to see whether melanoma has spread to the lymph nodes near the site where it started on the skin. During this procedure, a dye and/or radioactive substance is injected near where the melanoma started on the skin. Then, a special machine is used to find out which lymph nodes are most likely to contain melanoma cells. A surgeon can then remove these lymph nodes to check for melanoma cells.
Treatment
There are several treatment options for melanoma. They include surgery, chemotherapy, radiation, and immunotherapy. Immunotherapy boosts the body’s natural ability to fight cancer and may help keep it from coming back. Mayo Clinic doctors are conducting research to find more effective treatments for melanoma.
The most common treatment for melanoma is surgery to remove it. Doctors usually remove the tumor and a small amount of normal tissue around it, which is called a margin of safety. This helps prevent the melanoma from growing back at the same site. A doctor might also remove lymph nodes near the melanoma, which is a procedure called sentinel node biopsy.
Doctors can use chemotherapy to treat melanoma that has spread or is hard to reach. They might give it by vein (intravenous) or as tablets. Chemotherapy can cause many side effects, such as fatigue, risk of infection, hair loss, nausea and vomiting, changes in nail color, and diarrhea.
Ipilimumab, nivolumab, and pembrolizumab are drugs that block the interaction between 2 proteins on cancer cells and immune system cells. These drugs have been shown to improve survival in people with advanced melanoma. They are given along with other treatments, such as surgery and radiation, to treat melanoma that has already spread in the brain or elsewhere in the body. The FDA has approved a combination of these medications, called BRAF-directed immunotherapy, to treat some people with metastatic melanoma who have a BRAF mutation.