Word: basal
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...rising. One in 6 Americans will suffer from skin cancer, and the incidence is increasing nearly 4% annually. Of the 700,000 new cases that will be diagnosed in the U.S. this year, 80% will involve cells found in the lower layers of the epidermis. These so-called basal-cell cancers develop slowly, spread rarely and are nearly 100% curable. An additional 130,000 skin cancers affect the pancake-shaped cells that form the skin's upper layers. Although highly treatable, these squamous-cell carcinomas grow faster than basal-cell tumors and annually kill 2,300 Americans. Malignant melanoma, which...
...ozone layer, which blocks much of the sun's ultraviolet radiation, is contributing to the rise in skin cancer. While there is little evidence to support this notion, scientists agree that in the long run a diminished ozone layer will cause trouble. "Decreased ozone will increase numbers of basal- and squamous-cell carcinomas," says Dr. Stanford Lamberg, a Johns Hopkins dermatologist. "There is no question about that...
...skin's dynamic outer layer, or epidermis, serves as the staging ground for all three of the major skin cancers. Both basal-cell and squamous-cell carcinomas arise from the most common skin cells, the keratinocytes, which form at the base of the epidermis and work their way toward the surface. Near the base, they are plump and are called basal cells. But as they move outward, they flatten to become the squamous cells that form the skin's tough, protective surface. Melanomas spring from melanocytes, cells that produce pigment...
...ultraviolet light. After years of exposure to sunlight, the damage becomes visible first as small, scaly, precancerous spots called keratoses, usually on middle-aged or older people and in areas of the skin generally not protected by clothing. These spots can turn malignant, becoming translucent basal-cell nodules that slowly expand into adjoining tissue...
Unlike other cancers, basal-cell carcinomas rarely metastasize, or migrate to form tumors in other parts of the body. For that reason, many people regard these carcinomas lightly and unwisely put off corrective surgery. Doctors excising basal tumors that have gone too long without treatment must often remove large chunks of their patients' noses or ears, which then must be reconstructed surgically. Worse consequences can occur. "I've heard of only a few deaths due to basal-cell carcinomas," says Dr. Lamberg. "But if an unattended tumor on the head grew into the brain, for example, it could cause considerable...