“Skin cancer is an epidemic and it seems to be increasing in numbers every year,” said Dr. James Beckett, a dermatologist with the Palo Alto Medical Foundation.
Beckett, who regularly organizes and participates in sun safety education and skin cancer screenings in Santa Cruz County, said that he's made it his mission to “get people to protect themselves as best they can.”
Exposure to the Sun's ultraviolet rays — classified as UVA and UVB radiation — can cause long-term damage to the skin, and even potentially fatal health problems.
“(UVA and UVB rays) damage the DNA of our cells — it can lead to precancerous and cancerous skin lesions,” Beckett said, adding that the damage can accumulate for years before health problems will develop. “Mutations can take anywhere between 15 and 40 years — it can take that long for a cell to begin to grow abnormally quickly.”
Beckett described three types of skin cancers that can develop from sun exposure.
Basal cell carcinoma is the most common types of skin cancers Beckett said that he sees as a dermatologist, with an estimated 2 to 3 million new cases nationwide likely to be diagnosed in 2014 alone.
“That's probably the most common cancer in humans,” he said.
“It grows locally and it grows slowly,” he said.
Though it grows slowly, if left untreated, basal-cell carcinoma can lead to disfigurement as the cancer is allowed to invade adjoining tissues.
Most instances of basal-cell carcinoma, Beckett said, are caused by sunburning from UVB radiation.
Another skin cancer caused by excessive UVB sunburning, squamous-cell carcinoma is considered more dangerous than basal-cell carcinomas, as it can metastasize — meaning the cancer can spread to other areas of the body.
“These can be a little bit more aggressive,” Beckett said. “These are cancers that can spread to distant sites.”
He said that, in 2014, an estimated 250,000 to 300,000 new cases would likely be reported this year.
The most aggressive form of skin cancer, with the highest death rate, melanoma is cancer of skin's pigment-producing cells.
“(Melanoma) often spreads, or metastasizes, very quickly if not caught early,” Beckett said. “We're very concerned about melanoma because it is accelerating at a rate faster than any other cancer in humans.”
He said that the fastest-growing portion of the melanoma cases has been young women, between the ages of 20 and 30.
“Prior to 1950, the lifetime risk of someone getting melanoma was 1 in 1,500,” he said. “Now, it's 1 in 50.”
He said that much of the scientific evidence points to UVA exposure as one of the primary causes of melanoma. UVA radiation, Beckett said, is the type of rays that cause tanning of the skin.
“Many of these are young women who've spent significant amounts of time in tanning salons,” Beckett said. “There's a lot of info to suggest that tanning may be one of the major causes of melanoma.”
To combat the chances of getting skin cancer, Beckett said, the key is to limit the amount of time that bare skin is exposed to the Sun.
“Do everything you can to not let yourself get sunburned,” he said. “Thousands of cells will get damaged — it’s just not a healthy thing to do.”
If you plan to be outside in the sunlight, Beckett said, wear a broad-spectrum sunblock that blocks UVA and UVB rays.
When shopping for a sunblock, he said, don't buy anything rated less than a 30 sun-protection factor (SPF) — ideally, SPF 50 or higher — and be sure to check the labels for UVA and UVB protection, as well as sweat and water resistance.
“There's a huge emphasis now by the Food and Drug Administration to provide sunscreen that blocks as much UVB and UVA as possible,” Beckett said. “Read the labels to make sure they say 'broad spectrum.'”
In addition to sunblock, he advised that people protect themselves as much as possible by wearing tightly woven clothing, hats, and UV-protecting sunglasses, which can help prevent cataracts.