Basal Cell and Squamous Cell Carcinoma

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.

Diagnosis

Basal cell carcinoma and squamous cell carcinoma are generally diagnosed and treated in the same way. When an area of skin doesn't look normal, your doctor may remove all or part of the growth. This process is called a biopsy and is the only sure way to detect cancer.

Doctors generally divide skin cancer into two stages: local, affecting only the skin, or metastatic, spreading beyond the skin. Because skin cancer rarely spreads, a biopsy often is the only test needed to determine the stage. In cases where the growth is very large or has been present for a long time, your doctor will carefully check the lymph nodes in the area. In addition, you may need to have additional tests, such as special X-rays, to find if the cancer has spread to other parts of the body. Knowing the stage of a skin cancer helps the doctor plan the best treatment.

Treatment

 - Numerous treatment options are available for basal cell and squamous cell carcinoma. Your therapy will depend upon the type of skin cancer you have and its stage.

• Surgery

Many skin cancers can be cut from the skin quickly and easily. In fact, the cancer is sometimes completely removed at the time of the biopsy, and no further treatment is needed.

• Curettage and Electrodesiccation

Doctors commonly use a type of surgery called curettage. After a local anesthetic numbs the area, the cancer is scooped out with a curette, an instrument with a sharp, spoon-shaped end. The area is also treated by electrodesiccation. An electric current from a special machine is used to control bleeding and kill any cancer cells remaining around the edge of the wound. Most patients develop a flat, white scar.

Mohs' Surgery

Mohs' technique is a special type of surgery used for skin cancer. Its purpose is to remove all of the cancerous tissue and as little of the healthy tissue as possible. It is especially helpful when the doctor isn't sure of the shape and depth of the tumor. This method is used to remove large tumors, those in hard-to-treat places and cancers that have recurred. After being given a local anesthetic, the cancer is shaved off one thin layer at a time. Each layer is checked under a microscope until the entire tumor is removed. The degree of scarring depends on the location and size of the treated area.

Cryosurgery

Extreme cold may be used to treat pre-cancerous skin conditions, such as actinic keratosis -- a scaly or crusty bump on the skin that can be a precursor or first step in the development of skin cancer -- as well as certain small skin cancers. In cryosurgery, liquid nitrogen is applied to the growth to freeze and kill abnormal cells. After the area thaws, dead tissue falls off. More than one freezing may be needed to remove the growth completely. Cryosurgery usually doesn't hurt, but you may have pain and swelling after the area thaws. A white scar may form in the treated area.

Laser Therapy

Laser therapy uses a narrow beam of light to remove or destroy cancer cells. This approach is sometimes used for cancers that involve only the outer layer of skin.

Grafting

When a large cancer is removed, a skin graft sometimes is needed to close the wound and reduce scarring. For this procedure, your doctor takes a piece of healthy skin from another part of the body to replace skin that was removed.

Radiation Therapy

Skin cancer responds well to radiation therapy, also called radiotherapy, that uses high-energy rays to damage cancer cells and stop them from growing. Doctors often use this treatment for cancers that occur in areas that are hard to treat with surgery. Radiation therapy might be used for cancers of the eyelid, the tip of the nose or the ear. Several treatments may be needed to destroy all cancer cells. Radiation therapy may cause a rash or make skin dry or red. Changes in skin color or texture may develop after the treatment and may become more noticeable later.

Topical Chemotherapy

Topical chemotherapy is the use of anticancer drugs in a cream or lotion applied to the skin. Actinic keratosis, a scaly or crusty bump on the skin that can be a precursor or first step in the development of skin cancer, can be treated effectively with the anticancer drug fluorouracil, also called 5-FU. This treatment is also useful for cancers limited to the top layer of skin. The 5-FU is applied daily for several weeks. Intense inflammation is common during treatment, but scars usually do not occur.