CHICAGO, July 30 Melanoma, the most serious form of skincancer, accounts for more than 75 percent of all skin cancer deaths. Despiterepeated health warnings based on proven science that overexposure toultraviolet (UV) light is the most preventable cause of all skin cancers,including melanoma, many Americans are not properly protecting themselves fromthis known carcinogen. Now, new understanding of the emerging field of geneticepidemiology of melanoma and the factors that influence teens' use of indoortanning could shed more light on ways to protect future generations from skincancer.
At the American Academy of Dermatology's Summer Academy Meeting 2008 inChicago, dermatologist Martin A. Weinstock, MD, PhD, FAAD, professor ofdermatology and community health at Brown University in Providence, R.I., andchief dermatologist at Veterans Affairs Medical Center in Providence, led thepresentation of key findings from research that could pave the way for futureskin cancer prevention and treatment strategies.
Link Between UV Exposure and Melanoma: The Gene Factor
When it comes to melanoma, there are multiple types of melanoma that canoccur throughout the body and their relationship to UV exposure is differentfrom one type of melanoma to another. Dr. Weinstock explained that over thepast few years, the fields of genomics and genetic epidemiology have beenadvancing tremendously. The role of genetics in the study of melanoma is anattempt to understand the connection between genetic changes in melanomaassociated with different types of melanoma.
"Everyone is born with genes that are inherited from their parents," saidDr. Weinstock. "Sometimes the genes in certain skin cells become mutated,deleted or amplified over time due to UV radiation and other factors, andthese genetic changes in skin cells that take place could result in melanoma."
Different types of melanoma also are characterized by different geneticchanges. For example, Dr. Weinstock explained that a melanoma that occurs onthe face of an older person with extensive sun exposure will have a differentgenetic make-up than a melanoma found on the back or trunk area of a youngerperson with more limited exposure to UV light. From this greater understandingof the genetic characteristics of different types of melanomas, Dr. Weinstocksuggested that further research could show which preventative behaviors atdifferent ages could help decrease the incidence of age-related melanomas.
A greater understanding of the relationship between UV exposure andmelanoma could lead to more implications for treatment and preventivemeasures. For example, Dr. Weinstock noted that the oncology community ishopeful that a specific chemotherapy could be developed in the future thatwould target each type of melanoma based on where they occur on the body andtheir genetic characteristics.
"The better we understand the different types of melanoma, the more we candirect our therapies and prevention efforts," said Dr. Weinstock. "Since thesenew therapies won't be available anytime soon, it's still important for peopleto protect their skin from UV radiation from the sun and tanning beds."
Influences on Teens' Use of Indoor Tanning
Despite its link to both melanoma and squamous cell carcinoma, indoortanning is big business. In fact, published reports indicate that the indoortanning industry has an estimated revenue of $5 billion, a fivefold increasefrom 1992. The prevalence of indoor tanning among older U.S. teen girls is ashigh as 40 percent.
A multi-component project to identify the factors that influence thelikelihood of indoor tanning known as CITY 100 (Correlates of Indoor Tanningin Youth) examined the environmental, policy and individual level variablesthat may be related to teens' use of indoor tanning in 100 of the mostpopulous U.S. cities. The primary component used to g