Basal cell carcinoma (BCC) is the most common form of cancer, with about a million new cases estimated in the U.S. each year. Basal cells line the deepest layer of the epidermis. Basal cell carcinomas are malignant growths—tumors—that arise in this layer.

Basal cell carcinoma can usually be diagnosed with a simple biopsy and is fairly easy to treat when detected early. However, 5 to 10 percent of BCCs can be resistant to treatment or locally aggressive, damaging the skin around them, and sometimes invading bone and cartilage. When not treated quickly, they can be difficult to eliminate. Fortunately, however, this is a cancer that has an extremely low rate of metastasis, and although it can result in scars and disfigurement, it is not usually life threatening.

Cause

The sun is responsible for over 90 percent of all skin cancers, including BCCs, which occur most frequently on the sun-exposed areas of the body: face, ears, neck, scalp, shoulders and back.

Am I At Risk?

Anyone with a history of frequent or intermittently intense sun exposure can develop BCC, but a number of factors increase risk:

Time Spent Outdoors

People who work outdoors—construction workers, groundskeepers, lifeguards, etc.—are at greater risk than people who work indoors, as are those who spend their leisure hours in the sun.

Skin Type

Fair-skinned individuals who sunburn easily and tan minimally or not at all have a higher incidence of skin cancer than dark-skinned individuals.

Hours of Sunlight

The more hours of sunlight in the day, the greater the incidence of skin cancer. For example, there are more cases in Arizona, Texas and Florida—states that are closer to the equator and get more sun—than in the more northern states of Maine, Oregon and Washington.

Warning Signs

The five most typical characteristics of basal cell carcinoma are shown in the pictures below. Frequently, two or more features are present in one tumor. In addition, BCC sometimes resembles noncancerous skin conditions such as psoriasis or eczema. Only a trained physician can decide for sure. If you observe any of the warning signs or some other change in your skin, consult your physician immediately.