April 14, 2000 (Minneapolis) -- Just because you're black, doesn't mean you don't need sunscreen. Skin cancer rates for blacks go up as their exposure to sunlight goes up, just as they do in whites, according to a study in the journal Cancer Epidemiology, Biomarkers & Prevention.
"The study is a wake-up call for people with brown and black skin that [a dark complexion] may not protect you from skin cancer if you get a lot of sunlight," A. Paul Kelly, MD, tells WebMD. Kelly is professor and chief of dermatology at the King/Drew Medical Center in Los Angeles.
Researchers were particularly concerned about the role of ultraviolet-B (UVB) rays, the ones that cause skin cancer.
"This paper adds to the evidence that UVB radiation [from sunlight] can increase the risks of skin cancer in the black population," co-author Mitchell Gail, MD, PhD, tells WebMD. He is chief of the biostatistics branch at the National Cancer Institute's Division of Cancer Epidemiology and Genetics.
Co-author Susan Devesa, PhD, who is chief of the descriptive studies section of the biostatistics branch, says that black people vary widely in their degree of pigmentation and that light-skinned blacks, in particular, may benefit from using such preventive measures as sunscreen.
Previous studies have suggested that sunlight exposure and low levels of pigmentation -- the coloring of the skin -- put you at risk for skin cancer whether you are black or white, according to the study's authors. Other evidence also shows that the rate of skin cancer among blacks varied by geographic location in a manner similar to whites.
The authors collected information on a type of skin cancer known as melanoma, which is often fatal, and several other types of skin cancer, often grouped as "nonmelanoma skin cancer." The investigators considered data from melanoma cases among blacks and whites from 1973 to 1994 and from nonmelanoma cases from 1970 to 1981.
During those time periods, nearly 1,100 black men and more than 1,200 black women died of melanoma. More than 73,000 white men and almost 50,000 white women died of melanoma.
Nonmelanoma skin cancer killed 670 black men, 515 black women, more than 10,000 white men, and about 6,500 white women.
Researchers found that for black males, death rates from melanoma increased significantly with increasing levels of UVB radiation from sunlight. Nonmelanoma death rates also increased. But the death rates from melanoma in black women did not increase.
They also found that the risk of melanoma did not increase in either black men or black women. However, researchers found that blacks with melanoma are more likely of die of melanoma than are whites.
This is probably because blacks' melanoma may be diagnosed at a later stage than whites' melanoma, Kenneth G. Gross, MD, tells WebMD. "Because physicians do not expect to see melanoma in blacks, they may not be looking for it," says Gross, a specialist in dermatologic surgery and a professor of dermatology at the University of California, San Diego.
Although not proven, the researchers and commentators agree that blacks, especially light-skinned men, may benefit from sun-blocking agents when out in the sun.
- New research shows that skin cancer rates in blacks increase with higher levels of exposure to UVB radiation from sunlight.
- The overall risk and death from melanoma among blacks is still lower than among whites.
- Blacks, especially those who are light-skinned, may benefit from using protective measures such as sunscreen.