Skin cancer is the most common type of cancer. In fact, it’s so prevalent, one in five Americans will develop it at some point in their lifetime. But how do you know whether that spot on your skin is actually something serious? The skin is the body’s largest organ and needs to be checked out periodically. Preventive measures, such as using sunscreen and avoiding tanning beds, along with early diagnosis are key.
In this episode of San Diego Health, host Susan Taylor and guest Hugh Greenway, MD, chairman of the Mohs and dermatologic surgery center at Scripps Clinic, discuss the reasons why skin cancer occurs so frequently, the types of skin cancer, treatment options and a new gadget that pairs with your smartphone to track your skin health.
There is some positive news to report here, Dr. Greenway notes. “We used to talk about survival rates in terms of months, but now we talk in terms of years because of new immunotherapy drugs which specifically target melanoma,” says Dr. Greenway. “Now the five-year survival rate for melanoma today is higher than 90 percent.”
Dr. Greenway: Most of us grew up spending a lot of time outdoors. We have a lot more people that are living older now, so there's more time for you to get skin cancer than perhaps in the past. And a number of other factors: We had tanning beds in the past. We all wanted a bronze tan look. So just a variety of factors contributing to the incidence of skin cancer.
Dr. Greenway: The most common type is basal cell carcinoma, which actually is the least aggressive because it doesn't spread to the lymph nodes and the lungs like perhaps some others, but it's the one that we see more, probably about two million cases a year of basal cell carcinoma [are seen] in this country. Most commonly [they occur] in areas where we've got cumulative sun. So the head, neck, nose and ears are the most common areas for basal cell carcinoma.
The second most common skin cancer is called squamous cell carcinoma, and we see about a million [cases] in this country per year. Again, more in areas where you have cumulative sun exposure. We see a lot of these on the lower lip, on the back of the hands and also on the face. Squamous cell carcinoma does have a risk of spreading to lymph nodes and beyond, so it's a little bit more aggressive.
And then the third type is the most serious type and that is malignant melanoma or just melanoma. Any melanoma is malignant and we see about a hundred thousand cases of invasive melanoma [annually]...
Dr. Greenway: There are a number of ways that you can treat skin cancer.
The basal cell carcinoma can be treated surgically with radiation. If there are some superficial lesions there are actually some creams that one can apply. There was a drug called interferon that we [Scripps] were the first to use... So with basal cell carcinoma, there are a variety of techniques. Same with squamous cell carcinoma, although you have to be a little bit more careful with it... One of the techniques we use for the more invasive, aggressive ones is a technique called Mohs surgery.
[In Mohs surgery, the physician removes thin layers of skin until only cancer-free tissue remains. The procedure is designed to conserve healthy tissue and minimize scarring — especially for tumors on the face or near the nose, eyes, ears, forehead or scalp.]
Melanoma is the one that's the most dangerous. It's the one that has the higher risk of spreading if you don't get it early. Fortunately, we get most of those early. There's probably a million people alive in this country that have had melanoma. The cure rate is over 90 percent.
Dr. Greenway: We see more skin cancer among lighter-skinned individuals. If you have red hair, light-colored eyes and burn easily you're probably one of the ones at higher risk. The darker your natural pigment, the less risk although there is a risk that because your skin color may be darker it may not show up as early. So sometimes a melanoma in a darker skinned person may be more aggressive just because we don't get the diagnosis as early.
Fortunately, for melanoma today the five-year survival rate is 90-plus percent. Before it used to be just months because we didn't make the diagnosis early and we didn't have the treatment regimens that we have for advanced melanoma that has spread to lymph nodes or lungs or brain. [Former U.S. President] Jimmy Carter is a perfect example of [someone who survived] metastatic melanoma. Years ago we would talk about survival in terms of months now we talk about survival in terms of years...
Dr. Greenway: One of the things to realize is that most of us have gotten our sunburns and most of our cumulative sun exposure by the time we're in our mid-adult life, by the time you're 45, 50, 55. In other words, we were outdoors more when we were younger so it's a situation of being aware, but you don't have to become a hermit or anything like that. You're going to get some sun exposure, enough for your vitamin D, just walking to the car back and forth every day. So a little sun is fine but we really don't want you to go to a tanning salon to get a tan so you'll look good when you go to the beach, which is what people used to do.
So [sun exposure] is okay in moderation. But definitely we don't want you to get a sunburn.
Dr. Greenway: There's a small difference. A 30 will block out 90 percent of the bad rays, so beyond that you're really working in a small percentage. We grew up here in America and we kind of have this culture that if a little bit is good then a whole lot must be better. That's just the way we are. If you've got a 30 and a 50 you think: "Well maybe the 70 is better," and it may be because I'm going to be in and out of the water or there is a lot of wind blowing and stuff. But what we really want you to do is get into the use of [sunscreen] as a habit.
Dr. Greenway: If you're at high risk of if you've had skin cancer, we'll actually teach you to use mirror or a couple of mirrors and ask you to do it once a month...Living here in California, you should get checked [by a physician] at least once a year.
The most dangerous skin cancer is melanoma. Melanoma comes from a mole. In most cases, half of it is a mole you've had on your skin that changes.The average person has 20 to 40 moles on their body. They're there and you're really not aware of them. But if you have a mole that starts to itch or a mole that you're just aware of, that may mean that mole is starting to change and should be checked.
When we talk about [examining] moles we talk about the ABCDE [method] and we look at these for changes in the mole.
We use the A for asymmetry. Most of them [moles] are symmetrical, so if you've got one that's not symmetrical that could be an issue.
B is for borders. Most of the borders around a mole are regular but if you've got a border that's got several notches in it so it's an irregular border then that's another sign.
C is for color. Most moles are pretty much one color or brown...The classic melanoma is a black mole...
D is [for] different. So if that mole looks different from the others it may be a sign.
E is [for] evolving [or ] if the mole is changing.
We use those five, ABCDE. One of them by itself may not mean a lot but if you put the five together they can provide some information.
Dr. Greenway: Because of what they do to your skin. One is they significantly increase your risk of melanoma and the second is they make you look old...
The FDA first started looking at tanning beds in 2010. California was one of the first states that said for teenagers and minors "You can't go do that any more unless you parents say so." Tanning beds are now regulated in 44 states.