Skin Cancer

(Basal Cell and Squamous Cell Carcinomas)

Skin cancer is by far the most prevalent malignancy in the United Slates, with more than 800,000 cases a year. The two most common forms are basal cell carcinoma, which arises in the lowest part of the epidermis, or surface layer of the skin, and squamous cell carcinoma, which originates in the cells that make up the skins outer surface. Both types are readily curable if detected early and treated properly.

These two cancers are heralded by growths or skin sores that do not heal. A basal cell cancer is typically an irregular shape. It may appear as a flat spot or a firm lump that is scaly and crusty or smooth and shiny. A squamous cell cancer also appears as a scaly or crusty patch that may bleed occasionally. Squamous cell cancers develop most often on the rim of the ear, the mouth, and scalps of bald men. People with fair skin, red hair, and blue eyes are most vulnerable to both cancer types.

Excessive exposure to the sun's ultraviolet rays is the most common cause of skin cancer. Occupational exposure to coal tar, pitch, creosote, arsenic, and radium also increase the risk.

Diagnostic Studies and Procedures

A dermatologist often suspects skin cancer from the appearance of a sore or other lesion, but a skin biopsy is essential to make a definitive diagnosis and to determine the type.

These skin cancers rarely metastasize to distant parts of the body, but the squamous cell type may invade nearby organs. Thus, MRI or a CT scan may be ordered if the cancer is near the eyes or other pathway to the brain.

Medical Treatments

Removal is the usual treatment for skin cancer, although radiation is sometimes used when surgery is not possible. Chemotherapy with topical 5-fluorouracil may also be considered.

There are several different surgical methods; the choice depends on the cancer's appearance, size, location, and type. A small surface cancer can be treated with curettage -- the scraping away of the cancerous tissue with a sharp surgical instrument. Bleeding is stopped with electrodesiccation, the use of an electric needle that also cauterizes a zone of normal tissue surrounding the lesion, reducing the likelihood of recurrence.

Cryosurgery is the use of liquid nitrogen spray or a device called a cryoprobe to freeze the cancerous tissue and destroy the malignant cells with minimal scarring. Laser surgery can also be used to pinpoint and kill certain types of skin cancer cells.

Surgical excision involves removing the growth along with a margin of normal tissue, then closing the wound with stitches or skin clips. A skin graft and plastic surgery may be needed.

In the Mohs procedure, layers of tissue are cut away in an expanding circle around the cancer, and each layer is examined microscopically to determine the extent of malignant cells. Successive layers are removed until only normal tissue is found. Plastic surgery may be needed as a follow-up procedure.

Alternative Therapies

Meditation, hypnosis, and visualization can be helpful in controlling pain and promoting healing.

A diet that includes foods rich in antioxidants -- vitamins C, E, and A (or beta carotene, its precursor), can help protect against cancer. Vitamin E oil applied to the excised areas may hasten healing and reduce scarring, but check with your doctor before applying this (or anything else) to the wound.

Self-Treatment

While self-treatment cannot cure skin cancer, it is the key to prevention and avoiding recurrences. Because most skin cancers are related to damage from the sun's ultraviolet rays, you should minimize your exposure. Avoid being outside during the peak sunlight hours from 10 a.m. to 2 p.m. If you must be out then, wear a hat with a wide brim and loose-fitting but tightly woven clothing that covers most exposed skin. Use a sunscreen with a sun protection factor (SPF) of at least 15 on remaining exposed skin; reapply it often. For a baby, ask your doctor to recommend a safe sunscreen, and make sure that she wears a sun hat and protective clothing.

Remember that sand, snow, and water reflect the suns rays and thus magnify their potential harm to skin. Tanning booths and sun lamps can also give off harmful ultraviolet rays.

Other Causes of Skin Lesions

Moles, warts, and other benign skin growths and discolorations sometimes resemble skin cancer. Skin disorders such as psoriasis and dermatitis can be confused with malignant lesions.