The benefits of wearing sunscreen are well known after years of awareness campaigns to help prevent skin cancer. Yet, skin cancer remains the most common cancer in the United States. One in five Americans will develop skin cancer at some point in their lifetime.
Scripps skin cancer expert Hubert Greenway, MD, chairman of the Bighorn Mohs Surgery and Dermatology Center, joins San Diego Health host Susan Taylor to explain why skin cancer happens so frequently, who is most at risk, and what you can do to protect your skin.
Most skin cancers result from exposure to ultraviolet (UV) rays from sunlight, which is why preventive measures, such as regularly applying sunscreen, are so important. Basal cell carcinoma and squamous cell carcinoma are the most common and usually appear in sun-exposed areas, such as the neck, ears and eyes.
Melanoma is less common but it is the most serious type of skin cancer. Melanoma tumors can develop anywhere on the skin.
“Melanoma is the most dangerous skin cancer. It has the highest risk of spreading if you don't get it early,” says Dr. Greenway.
According to the American Cancer Society, more than 91,000 new melanomas will be diagnosed in the US in 2018, and about 9,320 people will die from the disease.
The risks of melanoma increase with age, which is one reason the number of cases has risen over the years, especially among older adults, Dr. Greenway says.
“Unfortunately, a lot of middle-aged people spent a lot of time in the sun and had a lot of sunburns in their younger years, which put them at risk. Also, tanning beds were popular until just a few years ago,” Dr. Greenway says.
The good news is, according to Dr. Greenway, that survival rates for melanoma have increased due largely to early detection and medical advancements.
“There are probably one million people alive in the United States that have had melanoma. The five-year survival is 90-plus percent,” says Dr. Greenway.
Dr. Greenway is widely recognized for his expertise in Mohs surgery. This surgical technique is used to treat common skin cancers and certain melanomas. It involves removing skin cancer layer by layer and examining the tissue microscopically until healthy, cancer-free tissue around the tumor is reached.
Dr. Greenway recommends self-exams and regular checkups with your primary care physician, or with a dermatologist if you’re at high risk. He encourages his patients to be on the lookout for unusual moles, which may be a sign of possible melanoma or another type of skin cancer.
When checking moles, Dr. Greenway recommends the "ABCDE" system:
- A is for asymmetry — one side looks different from the other.
- B is for border — it shouldn’t be irregular.
- C is for color — a classic melanoma is black.
- D is for different — does it look different from others?
- E is for evolving — the mole has somehow changed.
“The key with skin cancer is early detection,” Dr. Greenway says.
Anyone who spends time outdoors, especially in sunny places like San Diego, should be using sunscreen. Dr. Greenway recommends sunscreens with broad spectrum protection (against both UVA and UVB rays) and with an SPF of at least 30.
SPF stands for sun protection factor. It is the number that indicates the level of protection the sunscreen provides against sun rays. A higher number means more protection.
Dr. Greenway says there is only a small difference between SPFs of 30, 50, or 100, as SPF 30 sunscreens filter out about 97 percent of UVB rays. After that, the higher you go, the smaller the difference becomes, according to the American Cancer Society.
“What we really want you to do is to get into the habit of using sunscreen,” says Dr. Greenway.