Featured Research

from universities, journals, and other organizations

Sunscreens May Not Protect Against Melanoma Skin Cancer

Date:
February 18, 1998
Source:
Memorial Sloan-Kettering Cancer Center
Summary:
Sunscreens may not protect users from developing the deadly skin cancer, melanoma -- one of the fastest rising cancers in the United States, reports Dr. Marianne Berwick, an epidemiologist at Memorial Sloan-Kettering Cancer Center.

New York, February 17, 1998 -- Sunscreens may not protect users from developing the deadly skin cancer, melanoma -- one of the fastest rising cancers in the United States, reports Dr. Marianne Berwick, an epidemiologist at Memorial Sloan-Kettering Cancer Center.

"After examining the available epidemiological data and conducting our own large case-control population-based study, we have found no relationship between sunscreen use at any age and the development of melanoma skin cancer," said Dr. Berwick at the Annual Meeting of the American Association for the Advancement of Science (AAAS) in Philadelphia, Pennsylvania.

The logic behind using sunscreen stems from many studies in scientific journals and articles in the lay press that have linked a specific number of sunburns to an increased risk for developing melanoma skin cancer. But when Dr. Berwick re-examined these results in a large population-based study, she found that people's reports of their sunburn histories were unreliable.

"When asked the same question at different times, people often gave inconsistent answers about their sunburn history," said Dr. Berwick.

Examining the relationship between sunscreen use and the development of skin cancer is further complicated by evidence that people who are sensitive to the sun engage in fewer activities in the bright sun and wear sunscreen when they do. But Dr. Berwick reports that evidence suggests that when these people develop melanoma, it is because they are genetically susceptible and likely to develop skin cancer regardless of the amount of sunlight exposure or protection from sunscreen. Also, it is likely that those people who are normally sun sensitive may use sunscreens to stay out in the sun longer -- thereby eliminating sunburn, which would have otherwise signaled them to get out of the sun. Subsequently, these people expose themselves to more sun than they should.

"Based on the evidence, we conclude that sunburn itself probably does not cause melanoma, but that it is an important sign of excessive sun exposure particularly among those who are genetically susceptible because of their skin-type," said Dr. Berwick.

More powerful determinants for the risk of melanoma appear to be genetically determined characteristics such as the number of moles a person has and their pigmentary phenotype, or the combination of skin, eye, and hair color. In data gathered from Dr. Berwick's large population-based study, the risk for melanoma was estimated by looking at these genetic characteristics, sun exposure in early life, as well as sun exposure 10 years prior to the development of melanoma. Dr. Berwick found that the melanoma risk for people with numerous moles was six times higher than that of someone with only a few moles. The risk for melanoma with the most sensitive pigmentary phenotype (those with red or blond hair and lighter colored eyes) was almost six times that of someone with the least sensitive phenotype.

Increased amounts of sun exposure have also been linked to the alarming rise in melanoma incidence -- the highest rising cancer in men and the second highest in women, after lung cancer. But Dr. Berwick reports that epidemiologic studies show that to the contrary, people are spending less constant time outdoors and thus engaging in more intermittent sun exposure, which may explain the increase in melanoma rates.

"The evidence indicates that chronic sun exposure may be protective for the development of melanoma because the skin has adapted to the sun, having become thicker as it has tanned. On the other hand, intermittent sun exposure appears to increase risk, making it much less protective," added Dr. Berwick.

Given the data, blanket advice to the public to wear sunscreens as protection against melanoma skin cancer at any time outdoors is not warranted.

"People need to focus on their individual risk characteristics, such as their pigmentary phenotype, their family history, and the type and number of moles they have. I recommend that people avoid the sun when they are clearly at high risk and that they should enjoy a reasonable amount of outdoor activities with less anxiety when they are clearly at reduced risk," advised Dr. Berwick.

Memorial Sloan-Kettering Cancer Center is the world's oldest and largest private institution devoted to prevention, patient care, research, and education in cancer. Throughout its long, distinguished history, the Center has played a leadership role in defining the standard of care for patients with cancer. In 1997, Memorial Sloan-Kettering was named the nation's best cancer center for the fifth consecutive year by U.S. News and World Report.


Story Source:

The above story is based on materials provided by Memorial Sloan-Kettering Cancer Center. Note: Materials may be edited for content and length.


Cite This Page:

Memorial Sloan-Kettering Cancer Center. "Sunscreens May Not Protect Against Melanoma Skin Cancer." ScienceDaily. ScienceDaily, 18 February 1998. <www.sciencedaily.com/releases/1998/02/980218052957.htm>.
Memorial Sloan-Kettering Cancer Center. (1998, February 18). Sunscreens May Not Protect Against Melanoma Skin Cancer. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/1998/02/980218052957.htm
Memorial Sloan-Kettering Cancer Center. "Sunscreens May Not Protect Against Melanoma Skin Cancer." ScienceDaily. www.sciencedaily.com/releases/1998/02/980218052957.htm (accessed October 23, 2014).

Share This



More Health & Medicine News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
Powered by NewsLook.com
U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

Newsy (Oct. 22, 2014) Now that the U.S. is restricting travel from West Africa, some are dropping questions about a travel ban and instead asking about visa bans. Video provided by Newsy
Powered by NewsLook.com
US to Track Everyone Coming from Ebola Nations

US to Track Everyone Coming from Ebola Nations

AP (Oct. 22, 2014) Stepping up their vigilance against Ebola, federal authorities said Wednesday that everyone traveling into the US from Ebola-stricken nations will be monitored for symptoms for 21 days. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Doctors Help Paralysed Man Walk Again, Patient in Disbelief

Doctors Help Paralysed Man Walk Again, Patient in Disbelief

AFP (Oct. 22, 2014) Polish doctors describe how they helped a paralysed man walk again, with the patient in disbelief at the return of sensation to his legs. Duration: 1:04 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins