DefinitionBasal cell carcinoma is a slow-growing form of skin cancer.See also:Squamous cell skin cancerMelanomaAlternative NamesRodent ulcer; Skin cancer - basal cell; Cancer - skin - basal cellCauses, incidence, and risk factorsSkin cancer is divided into two major groups: nonmelanoma and melanoma. Basal cell carcinoma is a type of nonmelanoma 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