Skin Cancer

Basal Cell and Squamous Cell Carcinoma

Signs and Symptoms
Diagnosis
Treatment

Signs and Symptoms

The two most common kinds of skin cancer are basal cell carcinoma and squamous cell carcinoma, which are sometimes called nonmelanoma skin cancer. These cancers are carcinomas that begin in the cells that cover or line an organ.

Basal cell carcinoma accounts for more than 90 percent of all skin cancers in the United States and is the most common of all cancers. Typically, it is a slow-growing cancer that seldom spreads to other parts of the body.

Squamous cell carcinoma also rarely spreads, but does so more often than basal cell carcinoma. It is important that skin cancers are found and treated early because they can invade and destroy nearby tissue. Organ transplant recipients have a 65-fold higher risk of developing squamous cell carcinoma than others. UCSF Medical Center offers seminars to educate transplant recipients about the potential risk of skin cancer, including information on cancer appearance, early detection, preventive strategies and treatment options.

The most common warning sign of skin cancer is a change on the skin, especially a new growth or a sore that doesn't heal. The cancer may start as a small, smooth, shiny, pale or waxy lump. It also may appear as a firm red lump. Sometimes, the lump bleeds or develops a crust.

Actinic keratoses are pre-cancerous growths, usually caused by sun exposure. They often appear as red, scaly spots and may later develop a hard, wart-like surface. If untreated, about 1 percent develop into squamous cell carcinoma.

Both basal and squamous cell cancers are found mainly on areas of the skin that are exposed to the sun — the head, face, neck, hands and arms. But skin cancer can occur anywhere.

Reviewed by health care specialists at UCSF Medical Center.
Last updated May 8, 2007