Melanoma

Melanomas like those suffered by Sen. John McCain are more lethal than other types of skin cancers because the pigment-producing melanocytes that produce them are actually not skin cells at all. Though the basal cells and squamous cells that are responsible for the most common types of skin cancer are integral parts of the skin from the beginning, melanocytes are visitors -- nerve cells that are produced in the spinal column during infancy before migrating to the skin.

California is experiencing a "developing epidemic" of melanoma among Latinos, according to a study by USC researchers released Monday. Although the incidence is still much lower among Latinos than among whites, the researchers are alarmed because the greatest increase is in the rate of so-called thick tumors, which are much more likely to be lethal, according to a report in the journal Cancer.

African Americans are three times more likely than whites to be diagnosed with skin cancer when it is already in an advanced and possibly fatal stage, according to a study in Miami released Monday. Researchers pointed to a lack of public awareness about the risks of skin cancer for African Americans as well as Latinos, who are nearly two times more likely than whites to have a late-stage diagnosis. The research focused on melanoma, the deadliest form of skin cancer.

A biopsy of a small patch of skin removed from Sen. John McCain's right cheek showed no evidence of skin cancer, a spokesman for the Mayo Clinic in Scottsdale said. "No further treatment is necessary," the spokesman, Michael Yardley, said in a statement released through McCain's presidential campaign. The GOP nominee-in-waiting had the skin removed Monday as a precaution during a regular checkup with his dermatologist near Phoenix. The senator, who suffered severe sun damage from his 5 1/2 years in POW camps during the Vietnam War, gets an in-depth skin cancer check every few months because of a medical history of melanoma.

Peggy Maddox's life was saved by a movie and a cancer center named after a movie star. Maddox found a lump under her arm in the summer of 1983, a swollen lymph node characteristic of melanoma--the most deadly form of skin cancer. Surgeons near her Redondo Beach home removed the lump and pronounced her cured. By fall, she thought she had another lump, but the surgeons told her she was wrong, that she was OK.