Your risk depends on three factors
- Sun exposure
- Host factors
- Genetic factors
Sun exposure is the major cause of melanoma. Intense, intermittent sun exposure , characterized by sunburn is the single most high risk factor for developing a melanoma.
Number and type of moles:
If you have more moles you are at high risk of a melanoma. Presence of 11–25 moles conferred a 1.5-fold increase in risk compared with fewer than 10 moles. Individuals with more than 100 normal moles are at an almost seven times greater risk than individuals with few (≤15) moles.
Fair-skinned individuals have a much higher risk for developing melanoma than dark-skinned individuals. Skin reaction to the sun is also a predictor of melanoma risk. Skin that freckles easily has a tendency to burn or an inability to tan, increases the risk. Increased risk of melanoma among individuals with red or blonde hair, or blue or green eyes.
Certain genetic factors play a role but this work is still in development.