The incidence of melanoma has increased rapidly in the last half century, and officials at the American Academy of Dermatology, said about 50,000 Americans will be diagnosed with it this year.
The study, which analyzed the lifestyles and melanoma risks for women between the ages of 30 and 50, found what the researchers said was the strongest evidence yet that artificial sun tanning can be dangerous to healthy skin.
Melanoma risk is highest among fair-skinned people in Australia, New Zealand, Europe and North America. Since the 1950s, the rate of the skin cancer has tripled in Norway and Sweden, where light skin is common. About 50,000 cases of melanoma are diagnosed annually in the United States and about 7,500 people die of the disease each year, according to American Academy of Dermatology officials.
Researchers analyzed data from the Women's Lifestyle and Health Cohort Study in Norway and Sweden. In 1991 and 1992, 106,379 women completed extensive questionnaires about their exposure to sunlight and to artificial tanning. In 1999, the researchers rechecked the women's cancer status using the national health registries in Norway and Sweden.
The researchers found 187 cases of malignant melanoma diagnosed among the study group during the eight-year follow-up period.
They found that women of any age or hair color who regularly visited tanning salons once or more per month increased their chance of developing melanoma by 55 percent.
The risk was highest for young adults. Compared with women who never used a solarium, women who reported using artificial tanning systems once or more per month when they were between the ages of 20 and 29 increased their risk of melanoma by about 150 percent.
Researchers say their, results provide stronger evidence than those of other studies that the use of artificial tanning is associated with an increased risk of melanoma.
It is well known that ultraviolet light causes skin cancer, whether you get it at the indoor tanning parlor or at the beach, (UV light) is a carcinogen, say researchers.
Researchers say going to a tanning salon just for a cosmetic tan that fades in a couple of weeks could cause people a lifetime of trouble.
Melanoma is virtually 100 percent curable as long as it is limited to the skin. If allowed to grow, though, the cancer can penetrate to blood vessels and the lymphatic system and then spread rapidly throughout the body.
"If it spreads to the lymph nodes or to the internal organs, it is time to put your affairs in order", say doctors . Once it has spread, there's nothing that can be done . There are treatments that might buy some time, but that doesn't cure anybody.
In the study, researchers also found that the risk of melanoma from sun exposure was about twice as high for blondes than for women with dark brown or black hair. For red-haired women, the risk was about four times as high, the researchers said.
The presence of irregularly shaped moles, called nevi, also increases the risk of melanoma cancer, the study found. Women with a single nevus on the leg were about twice as likely to develop the disease. With more than seven nevi, the risk went up about 300 percent, the researchers report.