SQUAMOUS CELL CARCINOMA

Squamous cell tumors also occur on areas of your skin that have been in the sun, often on the top of the nose, forehead, lower lip, and hands. They may also appear on areas of your skin that have been burned, exposed to chemicals, or had x-ray therapy. Often this cancer appears as a firm red bump.

Sometimes the tumor may feel scaly or bleed or develop a crust. Squamous cell tumors may spread to the lymph nodes in the area (lymph nodes are small bean-shaped structures that are found throughout the body; they produce and store infection-fighting cells).

RISK FACTORS IN SQUAMOUS CELL CARCINOMA
The incidence of squamous cell carcinoma is on the rise in the general population, but few prospective studies have addressed possible risk factors. To fill the gap, researchers at Harvard University followed subjects in the Nurses' Health Study, whose cohort of 107,900 female, predominantly Caucasian nurses had been 30 to 55 years old in 1976. The eight-year project included 197 women with histologically confirmed squamous cell carcinoma diagnosed between 1982 and 1990; it analyzed possible risk factors, including hair color, number and severity of sunburns, and U.S. state in which the subjects had been born and lived at ages 15 and 30.

The results confirmed many of the risk factors suspected by most dermatologists. These included:

• red or light brown hair color
• living in California or Florida at birth and age 15
• number of severe sunburns
• childhood tendency to burn after two or more hours of sun
  exposure.
  

Current — but not past — cigarette smokers also had increased risk of developing squamous cell carcinoma. There was no correlation between risk and number of cigarettes smoked.

Grodstein F, Speizer FE, Hunter DJ; A prospective study of incident squamous cell carcinoma of the skin in the Nurses' Health Study. J Natl Cancer Inst 87:1061, 1995