Melanoma is a very serious type of skin cancer, which begins in skin cells known melanocytes. Even though melanoma primarily affects skin cells, it also can grow in the eyes; this is known as uveal melanoma. Melanocytes produce and contain melanin, which provides skin color and protects the deeper layers of the skin from the sun’s harmful ultraviolet (UV) rays. When people are exposed to UV light, from the sun or, for example, in a tanning booth, the melanocyte cells make more melanin and pack together tighter, resulting in darker skin tones. If the skin receives too much ultraviolet light, the melanocytes may begin to grow abnormally and become melanoma during this process. The risk of melanoma increases with age, and the average patient is diagnosed at 61 years old1.


What are the different types of melanoma?

There are several different types of melanoma that affect different layers of the skin. Read more about the different types of melanoma at:

What are the symptoms of melanoma?

Changes in the size, shape, or color of an existing skin growth, like:

  • spreading of pigment from the growth’s border to surrounding skin ● reddening or a swelling beyond the growth’s border
  • changes in growth skin sensation – itchiness, tenderness, or pain

Development of a new pigmented or unusual-looking growth on the skin, such as:

  • a sore that does not heal

How is melanoma diagnosed?

Physical exams will focus on suspect areas on the skin. The size, shape, color and texture of these areas will be noted, and the rest of the body will be examined for spots and moles.

Biopsy is the primary way melanoma is diagnosed. It entails removing a small piece of, or the entire skin growth suspected to be cancerous and examining it under a microscope. If the growth is melanoma, the dermatologist (skin doctor) will need to learn more about the behavior of the melanoma, like how thick the cancerous melanoma tumor is and how far it has spread. This process is also known as melanoma staging.

Imaging tests use x-rays, magnetic fields, or sound waves to create pictures of the inside of the body. For melanoma, these tests will include chest x-rays, computed tomography (CT) scans, magnetic resonance imaging MRI scans, and positron emission tomography (PET) scans.

What are the different stages of melanoma?

The system most often used to stage melanoma is the American Joint Commission on Cancer (AJCC) TNM system.

The TNM system describes 3 key pieces of information:

  • T stands for tumor (how far it has grown within the skin and other factors). The T category is assigned a number (from 0 to 4) based on the tumor’s thickness (how far down it has grown). It may also be assigned a small letter a or b based on ulceration and mitotic rate, which are explained below.
  • N stands for spread to nearby lymph nodes (bean-sized collections of immune system cells, to which cancers often spread first). The N category is assigned a number (from 0 to 3) based on whether the melanoma cells have spread to lymph nodes or are found in the lymphatic channels connecting the lymph nodes. It may also be assigned a small letter a, b, or c, as described below.
  • M category is based on whether the melanoma has metastasized (spread) to distant organs, which organs it has reached, and on blood levels of a substance called LDH.

What are the treatments for melanoma?

This melanoma treatment information does not outline the particular treatment(s) a patient will receive. Rather, it provides general information about the typical treatments used for this type of cancer.

Primary treatment options:

  • Surgery is the first treatment for all stages of melanoma. During surgery, a surgeon will attempt to remove the entire melanoma tumor along with about 3⁄4 inch of some surrounding tissues. This is called a wide excision. In some cases, a skin graft will be needed to replace the removed skin of the patient. Also, if the melanoma has spread nearby lymph nodes, the affected lymph node will be surgically removed. This procedure is called a lymph node dissection.

Secondary treatment options:

  • Immunotherapy is the use of medicines to stimulate the immune system to recognize and destroy cancerous melanoma cells more effectively. It is typically used for patients with advanced melanoma.
  • Targeted therapy is the use of drugs to prevent the growth of cancer cells and protect healthy skin cells from damage.
  • Chemotherapy employs drugs to treat cancer. Chemotherapy is usually not as effective in treating melanoma as it is in some other types of cancer, but it may relieve symptoms and/or extend survival time.
  • Radiation therapy uses high-energy rays or particles to kill cancer cells. Radiation therapy is often used to relieve symptoms caused by the spread of the melanoma, especially to the brain or bones. Radiation therapy is not used to cure melanoma, but it has the potential to shrink its tumor for a time to control some of the symptoms.

What are the risk factors of melanoma?

  • Ancestry: Those with Caucasian (white) ancestry are more likely to develop melanoma.
  • Skin pigment: Individuals with fair skin, light hair, and light-colored eyes are more likely to develop melanoma.
  • Personal history: A history of intense sun exposure, especially in childhood is correlated to higher rates of melanoma.
  • Moles: Having many (more than 100) moles or large, irregular moles puts a person at greater risk for melanoma.
  • Family History: Those with close blood relatives -- parents, siblings, and children -- with melanoma are at greater risk for this disease.

How is melanoma prevented?

  • Reducing the amount of time spent out in the sun, especially during the hottest times of the day.
  • Wearing protective sunscreen while outside is effective at reducing the impact of UV rays on skin.
  • Having regular skin exams (every 6-8 weeks) will help in the melanoma detection process. Look for irregular skin growths and have the growth examined by a healthcare provider if the growth promotes cause for alarm. 
Mikayla D. Williams , BS student, Nursing , The University of Arizona
Michael Principe, MA, Information Resources and Library Science
Works Cited: 
American Cancer Society (2014). Skin Cancer-Melanoma.
Works Consulted: 
Melanoma Research Foundation (2014). Understand Melanoma.
Skin Cancer Foundation (2014). Melanoma.