Definition of Basal cell carcinoma:

Basal cell carcinoma is a slow-growing form of skin cancer.

See also:

• Squamous cell skin cancer
• Melanoma

Causes, incidence, and risk factors:

Skin cancer is divided into two major groups: non-melanoma and melanoma. Basal cell carcinoma is a type of non-melanoma skin cancer, and is the most common form of cancer in the United States. According to the American Cancer Society, 75% of all skin cancers are basal cell carcinomas.

Basal cell carcinoma starts in the top layer of the skin called the epidermis. It grows slowly and is painless. A new skin growth that bleeds easily or does not heal well may suggest basal cell carcinoma. The majority of these cancers occur on areas of skin that are regularly exposed to sunlight or other ultraviolet radiation. They may also appear on the scalp. Basal cell skin cancer used to be more common in people over age 40, but is now often diagnosed in younger people.

Your risk for basal cell skin cancer is higher if you have:

• Light-colored skin
• Blue or green eyes
• Blond or red hair
• Over-exposure to x-rays or other forms of radiation

Basal cell skin cancer almost never spreads. But, if left untreated, it may grow into surrounding areas and nearby tissues and bone.