What are the causes and risk factors for melanoma?
Guideline # 5: Individual sunburns do raise one's risk of melanoma. However, slow daily sun exposure, even without burning, may also substantially raise someone's risk of skin cancer.
Factors that raise one's risk for melanoma include the following:
- Caucasian (white) ancestry
- Fair skin, light hair, and light-colored eyes
- A history of intense, intermittent sun exposure, especially in childhood
- Many (more than 100) moles
- Large, irregular, or "funny looking" moles
- Close blood relatives -- parents, siblings, and children -- with melanoma
The presence of close (first-degree) family with melanoma is a high risk factor, although looking at all cases of melanoma, only 10% of cases run in families.
Having a history of other sun-induced skin cancers, such as the much more common basal cell or squamous cell carcinomas, indirectly raises one's risk of melanoma because they are markers of long-term sun exposure. The basic cell type is different, however, and a basal cell or squamous cell carcinoma cannot "turn into melanoma" or vice versa.