Melanoma, the deadliest skin cancer, gets its name from the pigment-producing cells called melanocytes from which tumors can develop. These cells manufacture the dark pigment, melanin. When a human develops these cells, they populate not only the skin, but also other organs including the back of the eye and the nervous system.
Melanin strongly absorbs sunlight and helps to protect the skin from ultraviolet light that damages DNA, which can contribute to the development of cancer. Because people with dark skin have more protective melanin, they are at lower risk of developing melanoma than those with light skin. However, it should be kept in mind that individuals with any skin type can develop melanoma.
Melanoma often first appears as a superficial growth on the skin, but over time it can become invasive – growing deeper into the skin and metastasizing; that is when the cancer becomes life-threatening. The lifetime odds of developing invasive melanoma are – according to one’s ethnicity:
- White: 1 in 44
- Hispanic: 1 in 250
- Native American: 1 in 350
- Asian: 1 in 800
- Black: 1 in 1,100
Melanoma can occur anywhere in the body, though in individuals of African or Asian descent, melanoma usually develops on the soles of the feet or the palms; it can also develop under a finger or toenail. Importantly, for individuals of mixed descent, it is harder to predict melanoma risk. Your sun reactivity is a more accurate indicator of your risk of developing skin cancer.
To stay safe in the sun, be aware of how your skin type influences your risk of skin cancer. If you are very fair-skinned, with light or red hair, or have a lot of freckles, you are more susceptible to skin damage that can lead to skin cancers like basal cell carcinoma, squamous cell carcinoma and melanoma. It’s a good idea to have periodic skin checks by an expert to look for early signs of cancer.
People who are less likely to burn and easily tan are less at risk for skin cancers. But doctors advise people of all skin types to wear sunscreen, stay in the shade between 10 a.m. and 4 p.m., and to have skin checks by a health professional.
For more information, the Melanoma Treatment Center at Dana-Farber/Brigham and Women’s Cancer Center has expertise in treatment, prevention, and clinical research on this challenging form of skin cancer.