A risk factor is something that increases your likelihood of getting a disease or condition.

It is possible to develop melanoma with or without the risk factors listed below. However, the more risk factors you have, the greater your likelihood of developing melanoma. If you have a number of risk factors, ask your healthcare provider what you can do to reduce your risk.

Risk factors for melanoma include:

Excessive Sun Exposure

The occurrence of melanoma has been linked with exposure to UVA radiation that penetrates skin more deeply than UVB radiation. Therefore, exposing your skin to ultraviolet rays from the sun or tanning lamps increases your odds of developing melanoma. People who live in sunny climates are exposed to more sunlight. Also, people who live at high altitudes, where the sunlight is strongest, are exposed to more UV radiation. Blistering sunburns, even as a child, also increase the risk of developing melanoma.

Your Skin's Condition

Having melanoma once increases your risk of developing it again.

Having many moles or large moles from birth increases your risk of melanoma. Also, irregular moles are more likely to turn into melanoma than normal moles. Irregular moles are characterized by:

  • Being larger than normal moles
  • Being variable in color
  • Having irregular borders
  • Any pigmented spot in the nail beds
  • Changing in size and/or shape

Age

Most melanomas are diagnosed in young adults and older adults.

Genetic Factors

Family members of people with melanoma are at greater risk of developing the disease than people with no family history of the disease. People with a disease called xeroderma pigmentosa (XP) are at a very increased risk of developing melanoma. This rare disease does not allow patients to repair sun-damaged DNA, therefore any sun exposure will result in damage and mutations that become melanomatous. It is not unusual for these people to develop hundreds of melanomas on their skin. Similarly, people with hereditary dysplastic nevus syndrome or familial atypical multiple mole melanoma (FAMMM) syndrome are also at increased risk for developing melanoma.

FAMMM syndrome is an inherited condition marked by the following: (1) one or more first- or second-degree relatives (parent, sibling, child, grandparent, grandchild, aunt, or uncle) with malignant melanoma; (2) many moles, some of which are atypical (asymmetrical, raised, and/or different shades of tan, brown, black, or red) and often of different sizes; and (3) moles that have specific features when examined under a microscope. FAMMM syndrome increases the risk of melanoma and may increase the risk of pancreatic cancer.

Ethnic Background

Caucasians are more likely than black, Hispanic and Asian people to develop melanoma.

Complexion

Most people who develop melanoma tend to burn rather than tan when exposed to sunlight. These people tend to have fair skin, freckles, red or blonde hair, or blue-colored eyes.