What is squamous cell carcinoma (SCC)?

• SCC is the second most common type of skin cancer.

What does it look like?

• It usually looks like a scaly or crusty bump.

• It also can appear as a nonhealing sore or ulcer.

Squamous cell carcinoma

Where does it appear?

• It's most often seen on sun-damaged skin. It's found mainly on sun-exposed areas—the face, especially the nose, the temples and forehead, and the lips.

• It's also commonly noted on the bald areas of the scalp and the tops of ears in men, the top of the forearms and hands, and the sun-exposed areas of the neck.

• In addition, it may also occur on any area that is repeatedly exposed to the sun.

• It may occur on the legs in women.

Squamous cell carcinoma

Who gets it?

• Because SCC is related to sun exposure, it's noted more frequently in those with a greater degree of outdoor activity. It is seen in people who are fair-skinned, burn easily, and tan poorly.

• It's more common in men, particularly those who work in outdoor occupations, such as farmers, sailors, and gardeners, and those who participate in outdoor sports.

Where does it come from?

• In most cases, it arises in a solar keratosis, a precancer also known as an actinic keratosis.

• Causes other than sun exposure include the following:

  • Radiation exposure

  • Tanning parlors, exposure to psoralens with ultraviolet A (PUVA) phototherapy

  • Exposure to coal tar

  • Immunosuppression by medications or disease such as HIV

How is it diagnosed?

• Diagnosis is generally made by shave or excisional biopsy.

How is it treated?

• Most often, a simple minor office procedure called electrodesiccation and curettage is performed for small growths and for very superficial SCCs, known as squamous cell carcinoma in situ.

• Surgical excision is the preferred method for larger tumors.

• Micrographic (Mohs') surgery may be the preferred method for recurrent or very large lesions. Mohs' surgery is a microscopically controlled method of removing skin cancers that allows for controlled excision and maximum preservation of normal skin. Excisions are repeated in the areas proven to be cancerous until a completely cancer-free specimen is obtained.

• Other treatment methods include the following:

  • Cryosurgery (freezing) with liquid nitrogen

  • Radiation (x-ray) therapy, which is used for those patients who are physically debilitated or who are unable, or refuse, to undergo excisional surgery

How is it prevented?

• Sun avoidance measures:

  • Sunscreen

  • Hat with brim

  • Sunglasses with UV protection

  • Tinted windshields and side windows in cars

  • Protective clothing made of tightly woven or knitted fabrics that allows less sunlight to pass through

• Follow-up: after therapy, periodic skin examination months after treatment