Basal cell cancer

Alternative names:

cancer of the skin (basal cell); rodent ulcer; skin cancer - basal cell

Definition:

A malignant skin tumor involving cancerous changes of basal skin cells.

Causes, incidence, and risk factors:

A new skin growth that ulcerates, bleeds easily, or does not heal well could indicate development of basal cell skin cancer. Skin cancer has a high cure rate if treated early, but neglect can allow the cancer to spread, causing disability or death.

Basal cell cancer is the most common form of malignant skin cancer. It accounts for about 75% of all skin cancers. The incidence of skin cancer has increased greatly. In 1990, 600,000 Americans were diagnosed with either basal cell cancer or squamous cell cancer, up from 400,000 in 1980.

Over 90% of basal cell skin cancers occur on areas of skin that are regularly exposed to sunlight or other ultraviolet radiation. This is considered the primary cause of most skin cancers. Other risks include a genetic predisposition (basal cell skin cancers are more common in those who have light colored skin, blue or green eyes, blond or red hair) and over-exposure to X-rays or other forms of radiation. Exposure to arsenic, which may be present in certain herbicides, is another risk factor for developing skin cancers.

Most basal cell cancers occur on areas of the body that are regularly exposed to ultraviolet radiation (sunlight). They may also occur on the scalp. The onset most commonly occurs after age 40.

Basal cells are normal skin cells. They may develop cancerous changes, causing a patch or lump that is painless. The lump may grow slowly, ulcerate, and never heal completely. It usually remains local and almost never spreads to other parts of the body, but it may continue to grow and invade nearby tissues and structures, including the nerves, bones, and brain. The tumor may be very small, growing to 1 or 2 centimeters in diameter after several years of growth.