The ... rise in nonmelanoma skin cancer rates may lead to an exponential increase in these cancers as the population continues to age.
Through the efforts of organizations including the American Academy of Dermatology (AAD), the American Society for Dermatologic Surgery (ASDS) and the American College of Mohs Micrographic Surgery and Cutaneous Oncology (ACMMSCO), "dermatologists are doing an excellent job of getting the skin cancer prevention message out," Leslie J. Christenson, M.D., says. Dr. Christenson is a dermatologic surgeon at the Mayo Clinic and the study's lead author.
"Our results say more about society. There's such a strong belief that a tan is a sign of beauty and health that our prevention message is not being translated into people's behavior. That's something we need to continue to work on."
She says she and her co-authors undertook the study because they noted an apparent increasing incidence of skin cancers in ever-younger patients.
"Because we are a group of dermatologic surgeons," Dr. Christenson explains, "we thought perhaps we were simply seeing a selection bias." Although the study's conclusions came as no shock, she adds, "the rise in BCC among women being almost threefold over a 25-year period was a bit surprising."
In short, a population-based, retrospective incident case review utilizing Rochester Epidemiology Project data for Olmsted County, Minn., found that between 1976 and 2003, 451 incident BCCs were diagnosed in 417 patients, and 70 incident BCCs were diagnosed in 68 patients. Among these tumors, histologic analysis, where available, confirmed and subtyped 328 BCCs and 51 SCCs (Christenson LJ et al. JAMA. 2005 Aug 10;294(6):681-690.).
Gender, BCC incidence
Perhaps more importantly, researchers say their study has shown that the age-adjusted incidence of BCC during the study period increased significantly among women but not among men. For women, the study revealed an overall age-adjusted BCC incidence per 100,000 persons of 25.9 (95 percent CI); for men, the corresponding figure was 20.9 (95 percent CI). Between 1976 and 2003, women's age-adjusted BCC incidence per 100,000 persons climbed from 13.4 to 31.6, while the corresponding figure for men rose from 22.9 to 26.7.
Gender, SCC incidence
The incidence of SCC, on the other hand, increased significantly over the period studied among both women (P=0.01) and men (P=0.04), with an average age-and sex-adjusted incidence per 100,000 persons of 3.9 for both genders.
Though the study didn't specifically address why nonmelanoma skin cancer rates are rising, Dr. Christenson tells Dermatology Times, "one would say the biggest cause of skin cancer is UV light; therefore, probably the biggest cause in this rise is too much UV exposure, from both natural sunlight and tanning beds."
The study's authors express concern that the rise in nonmelanoma skin cancer rates may lead to an exponential increase in these cancers as the population continues to age.
"Individuals who get one nonmelanoma skin cancer have a 50 percent risk of getting a second within two to three years. Seventy-five percent of those individuals who get two nonmelanoma skin cancers will have a third. So if these individuals start getting nonmelanoma skin cancer in their 30s instead of their 60s or 70s, they're going to face a lifetime of increased risk," Dr. Christenson says.