Squamous cell carcinoma, a cancer of the epidermis, the top layer of the skin, is the second most common type of skin cancer, affecting 200,000 to 300,000 people in the United States each year, the Merck Manual states. Around 2,000 people in the U.S. die each year from the disease. While squamous cell carcinoma may look and behave differently in different people, it has certain characteristics common to most people with the disease.
Susceptibility
Squamous cell carcinoma is more common in people over age 50, men, and in fair skinned people with light colored eyes. Dark skinned and dark eyed people can develop the disease, however. Smokers are also more likely to develop the disease, as are people with a history of skin diseases such as psoriasis, the Mayo Clinic states.
Squamous cell cancer occurs more frequently in people who have spent a lot of time in the sun, and is also more common in areas where skin is damaged from burns, radiation or chemical exposure, the Milton S. Hershey Medical Center states. Skin that's exposed to sun, such as the tips of the nose, top of the head, neck, hands, shoulders, arms, lips and ears are most likely to develop squamous cell cancer, but lesions can also develop inside the mouth, or on areas not exposed to the sun.
Precursors
Certain types of skin damage may be seen before squamous cell carcinoma appears. Actinic keratoses, rough, small pink or brown patches of skin, may turn into squamous cell cancer is some cases, the Mayo Clinic states.
Symptoms
People with squamous cell carcinoma that hasn't metastasized, or spread to other areas, don't generally have any systemic symptoms; the only symptom is the lesion. Squamous cell cancer may start as scaly or crusty flat lesions that become raised, reddened and wart like. Squamous cell carcinoma in the mouth may look like a white patch or ulcerated area. A hornlike projection may grow from the lesion, Hershey Medical Center explains.
Growth
Squamous cell cancer normally grows slowly but can metastasize to other areas. Survival rates with early diagnosis and treatment are excellent. As many as a third of squamous cell carcinoma in the mouth or on the tongue metastasize before they're diagnosed; the 5 year survival rate for metastases is 34 percent, Merck reports. Tumors on the lips and ears are also likely to recur or spread.
Treatment Response
Squamous cell carcinoma responds to several types of treatment. Chemotherapy drugs can be applied in topical form to superficial cancers; lasers are often used to treat lip cancers. Small squamous cell carcinoma in areas other then the face can be treated by freezing; deep cancers may be cut out of the skin. Radiation may be used for deeper or larger squamous cell carcinomas. Mohs surgery is a method of removing one layer at a time and looking at each layer under the microscope until all layers with cancer cells are removed.
