Melanoma is the least common type of skin cancer, but the most deadly. It accounts for approximately four percent of all skin cancer cases, but approximately 80% of skin cancer deaths. Melanoma can be challenging to diagnose. The Myriad myPath™ Melanoma test uses a gene signature to objectively differentiate malignant melanoma from benign skin lesions with a high degree of accuracy.

Skin cancer is one of the most common forms of cancer. Melanoma is the most serious form of this cancer and, even though it accounts for less than five percent of all skin cancers, it is responsible for the majority of skin cancer deaths.  The cancerous growths develop when unrepaired DNA damage to skin cells – most often caused by ultraviolet radiation from the sun or tanning beds – triggers mutations that cause skin cells to multiply rapidly and form malignant tumors.  Melanomas often resemble moles and some of them actually develop from moles. The majority of melanomas are black or brown, but they can also be skin-colored, pink, red, purple, blue or white. If melanoma is caught and treated early, it is almost always curable.  However, if it is not, the cancer can advance and spread to other parts of the body, where it becomes hard to treat and can even be fatal. Myriad has developed a test called Myriad myPath™ Melanoma that can differentiate malignant melanoma from noncancerous moles and therefore improve treatment options for patients.

Facts about Melanoma

  • Melanoma is one of the easiest cancers to detect because it is readily visible on the skin.
  • From 1970 to 2009, the incidence of melanoma increased by 800 percent among young women and 400 percent among young men.
  • Melanoma is the most common form of cancer for young adults 25-29 years old and the second most common form for young people 15-29 years old.
  • The American Cancer Society estimates that there will be approximately 76,000 new melanoma cases diagnosed and almost 10,000 people are expected to die of the disease in 2014. The rates of melanoma have been rising for at least 30 years.
  • Of the seven most common cancers in the U.S., melanoma is the only one that is increasing – it rose 1.9 percent annually between 2000 and 2009.
  • One person dies of melanoma every 57 minutes.
  • There are almost 950,000 men and women alive in the U.S. today who have a history of melanoma.
  • Survival with melanoma increased from 49 percent in the 1950s to 92 percent between 1996 and 2003.
  • The overall five-year survival rate for patients whose melanoma is detected early is about 97 percent in the U.S. The survival rate falls to 62 percent when the disease reaches the lymph nodes and 15 percent when it spreads to other organs.

Risk Factors for Melanoma

  • Skin Type: Melanoma is more than 20 times more common in whites than in African Americans. Overall, the lifetime risk of getting melanoma is about 2 percent (1 in 50) for whites, 0.5 percent (1 in 200) for Hispanics and 0.1 percent (1 in 1,000) for blacks. Regardless of their skin type, everyone should take precautions to protect themselves from UV exposure.
  • UV Radiation Exposure: Whether it is from the sun or indoor tanning beds, UV radiation exposure is the most frequent and the most preventable risk factor for developing melanoma. Although one or more severe, blistering sunburns during childhood increases the risk, so does ongoing exposure over a lifetime. One bad sunburn before the age of 16 can actually double the lifetime risk of developing melanoma. Living and/or working in sunny climates or at high altitudes adds to this risk. The amount of radiation produced by a tanning bed is similar to the sun and, in some cases, might even be stronger. Studies have found a 75 percent increase in the risk of melanoma in individuals who have been exposed to UV radiation from indoor tanning. Even occasional use of tanning beds can triple the risk.
  • Family History and Genetics: People who have a first-degree relative (parent, sibling or child) with melanoma are two to three times more likely to develop the disease than the general population. For those with many close family members with melanoma, the risk increases from 30 to 70 times. Approximately 10 percent of patients with melanoma have a family history of the disease. Genetic mutations have been found in 10 to 40 percent of families with a high rate of melanoma. However, many people who inherit a genetic susceptibility never develop melanoma. Individuals with these gene mutations may have 50+ common moles (small growths on the skin that are usually pink, tan or brown and have a distinct edge) or five atypical moles – a condition called dysplastic nevus syndrome. When this syndrome is inherited and there is a family history of melanoma, people are considered to have Familial Multiple Mole and Melanoma or FAMM and they are at very high risk of developing the disease.  Go to Hereditary Melanoma to learn more.
  • Other Risk Factors: Other risk factors for melanoma include a weakened or suppressed immune system as a result of having a different type of cancer, the AIDS virus or an organ transplant. In addition, coming into contact with cancer-causing chemicals such as arsenic, coal tar, creosote, pitch or radium may cause the disease.

Hereditary Melanoma

Approximately 10 percent of melanoma cases are hereditary.1 Several genes have been associated with hereditary melanoma, including the p16 gene (also known as CDKN2A).2,3  Mutations in this gene account for 20-40 percent of hereditary melanoma cases and are likely responsible for approximately 1400-2800 new melanoma cases in the U.S. each year, making these mutations the most significant known cause of hereditary melanoma.  These mutations are also associated with an increased risk of pancreatic cancer in some families.

risk of melanoma and pancreatic cancer in patients with p16 mutation

 

Assessing Your Risk of Hereditary Melanoma

In order to determine your risk of carrying gene mutations associated with hereditary melanoma, your healthcare professional may ask you about your personal and family cancer history. Knowing your potential risk for hereditary melanoma can help you and your healthcare professional make better, more informed decisions about your health, before the onset of cancer or before a second cancer has had a chance to develop.

 

To help you assess whether you may benefit from hereditary cancer genetic testing, take the Myriad Hereditary Cancer Quiz. This quiz can help you get the information you need to discuss your risk of cancer with your healthcare professional and ask for further evaluation.

References

1. American Cancer Society. Melanoma Skin Cancer. Available at http://www.cancer.org/cancer/skincancer-melanoma/detailedguide/

2. Greene MH (1999) The genetics of hereditary melanoma and nevi. 1998 update. Cancer 1999 86:2464-77.

3. Bishop DT, Demenais F, Goldstein AM, et al. Geographical variation in the penetrance of CDKN2A mutations for melanoma. J Natl Cancer Inst 2002;94(12):894-903.