Basal cell carcinoma Basal cell carcinoma begins in the basal cells — a type of cell within the skin that produces new skin cells as old ones die off. Basal cell carcinoma often appears as a change in the skin, such as a growth or a sore that won't heal, or a slightly transparent bump on the skin.
Squamous cell carcinoma Squamous cell carcinoma is a common form of skin cancer that develops in the squamous cells that make up the middle and outer layers of the skin. Signs and symptoms of squamous cell carcinoma of the skin include a firm, red nodule; a flat sore with a scaly crust; and a new sore or raised area on an old scar or ulcer.
Melanoma While melanoma accounts for only about 1% of skin cancers, it causes most skin cancer deaths, according to the American Cancer Society. Melanomas develop in the cells that produce melanin — the pigment that gives your skin its color. The first sign of a melanoma often is a mole that changes size, shape or color. Your eyes also have melanin-producing cells and can develop melanomas. Eye melanoma, also called ocular melanoma, most often forms in the part of the eye you can't see when looking in a mirror, which makes it difficult to detect.
Skin cancer develops primarily on areas of sun-exposed skin, including the scalp, face, lips, ears, neck, chest, arms, hands and legs. But skin cancer also can form on areas that rarely see the light of day, including your palms and the soles of your feet, beneath your fingernails or toenails, and your genital area.
Skin cancer affects people of all skin tones, including those with darker complexions. However, having less pigment in your skin provides less protection from damaging UV radiation. If you have blond or red hair and light-colored eyes, and you freckle or sunburn easily, you're much more likely to develop skin cancer than a person with darker skin.
You can reduce your risk of skin cancer by limiting or avoiding exposure to ultraviolet, or UV, radiation, with these strategies:
Avoid the sun during the middle of the day.
Wear sunscreen year-round.
Wear protective clothing.
Avoid tanning beds.
Be aware of sun-sensitizing medications.
Check your skin regularly and report changes to your health care team.
Connect with others talking about preventing skin cancer in the Skin Health support group on Mayo Clinic Connect, an online patient community moderated by Mayo Clinic.