By PAUL RECER, AP Science Writer
WASHINGTON (AP) - People who seek a glamorous tan using sun lamps may double their risk of developing some common types of skin cancer, according to a new study that found the risk was highest for those who start at a young age.
The study, appearing Wednesday in the Journal of the National Cancer Institute, concluded that people who use tanning devices were 1.5 to 2.5 times more likely to have common kinds of skin cancer than were people who did not use the devices.
The study confirmed what doctors and other health care workers have long suspected -- that sun lamp use increases the risk of basal cell and squamous cell skin cancers, said Margaret R. Karagas, first author of the study.
"Even though we suspected tanning lamps might cause these types of skin cancers, there really hadn't before been epidemiological studies that addressed that issue," she said.
Dr. James Spencer, vice chairman of the department of dermatology at Mount Sinai Hospital in New York and an expert spokesman for the American Academy of Dermatology, praised the study as confirming in humans what has already been shown in animal studies -- "it is actually worse to go to the tanning parlor and get a little bit each day" than it is to get an infrequent sunburn.
Both can seriously damage the skin, he said, but the small, day-to-day exposure is worse for the skin in the long run, he said.
"The tanning industry has said ... as long as you don't burn you'll be OK," said Spencer. "This study shows that this is not true."
Joseph A. Levy, vice president of the International Smart Tan Network and a spokesman for the Indoor Tanning Association, however, said the study "is not an indictment of commercial tanning facilities in any way."
He said that occasional sunburn "is a risk factor in all forms of skin cancer and intermittent sunburn is what the tanning industry is trying to stop."
Levy said there are about 25,000 tanning salons in the U.S. He said it is a $5 billion industry patronized annually by about 28 million Americans.
In the study, Karagas and her colleagues interviewed 603 basal cell skin cancer patients and 293 with squamous cell skin cancer. They also talked to 540 control subjects, people who did not have either type of skin cancer.
About 1 million Americans are diagnosed annually with skin cancer. About 80 percent are basal cell; 16 percent squamous cell, and 4 percent are melanoma, the most serious form of skin cancer.
Melanoma patients were not included in the study.
The study interviews included questions about tanning device use at any point in the patients' lives and about other sun exposures.
Among the skin cancer patients, 190 reported that they had used tanning devices at some time. In the control group, only 75 had used tanning devices.
Karagas said a statistical analysis shows that those who used tanning equipment were 2.5 times more likely to get squamous cell skin cancer than were people who had not used the devices. For basal cell cancer, the risk was 1.5 time greater.
The risk was highest for those who first used the tanning devices before the age of 20, said Karagas. For this group, the squamous cell cancer risk was 3.6 times greater than the controls.
The basal cell cancer risk was 1.8 times greater.
The researcher said the statistics were adjusted for the effects of routine normal sun exposure and other factors that might contribute to skin cancer.
Levy said the study is not relevant to the modern tanning industry because most of the patients interviewed were exposed to tanning equipment before 1975.
"Indoor tanning facilities did not come into play (in the U.S.) until 1979," said Levy.
Thus, he said, many of the people interviewed for the study must have improperly used home sun lamps. Commercial tanning parlors, said Levy, use calibrated equipment that carefully regulates and controls exposure.