Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, October 14, 1993 TAG: 9310140039
SECTION: NATIONAL/INTERNATIONAL PAGE: A-13 EDITION: METRO
SOURCE: Associated Press
DATELINE: BOSTON LENGTH: Medium
Rubbing on sun-blocking cream has long been recommended as a way to protect the skin from the sun's harmful effects, including cancer. But this advice had been based on circumstantial evidence, such as animal experiments.
Now, Australian researchers have conducted a summer-long experiment showing that people who used sunscreen before going outside cut their chances of developing the first signs of skin cancer.
"It's a very important paper," commented Dr. Darrell Rigel of New York University Medical School. "It's the first time we have been able to definitively show that sunscreen lowers the risk of getting skin cancer later in life."
The study was conducted on 588 men and women who were randomly assigned to use either SPF-17 sunscreen or a look-alike dummy lotion from September 1991 through March 1992, one Australian summer.
Then they were checked for solar keratoses - small, wart-like growths that result from overexposure to the sun.
These growths are forerunners of squamous-cell skin cancer, a common, usually harmless form of skin cancer. They also signal increased risk of melanoma, the much rarer and lethal skin cancer, although they do not directly lead to these cancers.
The researchers, whose study was published in today's New England Journal of Medicine, found that the sunscreen users averaged a net loss of about one keratosis and those in the comparison group gained one.
The study was conducted by Dr. Sandra C. Thompson and colleagues from the Anti-Cancer Council of Victoria and the University of Melbourne. It was funded by grants from several nonprofit Australian health organizations.
About 700,000 Americans are diagnosed annually with squamous or basal cell cancers. Both are easily treatable. About 32,000 get melanoma, which spreads quickly and is deadly unless recognized early. Over the past 20 years, the incidence of melanoma has increased about 4 percent a year, and too much sun exposure largely is blamed.
In the study, the volunteers were instructed to put sunscreen on their heads, necks, arms and hands every morning and to reapply it during the day, if necessary.
Even though the subjects' exposure probably was relatively modest, the sunscreen clearly cut the risk of precancerous growths.
by CNB