The Dermatology Blog

Yes. Isn’t the answer obvious? Doesn’t everyone know that the sun causes melanoma? Not so fast.

There are many people who think we dermatologists are needlessly frightening everyone. They argue that the sun is good for you because it boosts your vitamin D levels and that dermatologists are subsidized by the sunscreen industry. They argue that melanoma can occur in places that are not sun exposed (like the bottom of your feet), that sunscreens have never been proven to prevent melanoma, and that people who get sun every day, like farmers, are actually less likely to get melanoma. They’re right.

So, then does the sun cause melanoma? Yes. Melanoma is a potentially deadly skin cancer. Like other cancers (breast, lung, colon), there are many risk factors. Think of melanoma as a destination — the hell of skin cancer. There are many roads to that destination even though the final resting place is the same.

People who have light skin or a family history of melanoma have a much shorter route to arrive at melanoma. It takes less time and less environmental factors for them to get melanoma. People who have very dark skin have a very long road to melanoma; it is unlikely that they will arrive there in their lifetime. Older people are much more likely to develop melanoma than younger people (they have been travelling the road for much longer). Sun exposure, especially sun burns, pushes you farther down that road.

Brilliant research from people like Dr. Michael Stratton in the United Kingdom has shown that most of the mutations found in melanoma tumors are unquestionably the work of ultraviolet radiation damage to the DNA. We also know that people who use tanning beds before the age of 30 are 75% more likely to develop melanoma that those who do not.

The sun does have health benefits, but unfortunately it also is the main driver pushing us down the road to melanoma. Each person has to think about how far along the road to melanoma he or she is starting at to determine how careful to be with the sun.

Everyday in dermatology we see people who unexpectantly find themselves in a place they did not think possible — they have melanoma. Many don’t understand how they got there; it has been a long road. Stop and think about where you are along that journey. What are your risk factors of melanoma? It is never too late to stop and turn around.

Photo: Eduardo Amorim

Lots of women have been Going Red lately. “Go Red” is a campaign to raise awareness of heart disease in women. Some women I see are often going red for a different reason: they’re covered in little red spots called cherry angiomas.

Cherry angiomas are tiny lumps of overgrown blood vessels in the skin. Their name derives from their often bright or deep red color. Like a cherry. Get it?

In your thirties and forties you might have a few. By the time you’re 80, you’ll probably have many (hence their other, more unfortunate name: senile angiomas). They cluster on the chest and back and can number in the hundreds. Although they grow on men and women equally, women are more likely to see a physician to have them checked.

Cherry angiomas are harmless, but many people hate the way they look. Fortunately, they’re easy to treat. Each little red spot represents a tiny, tangled knot of blood vessels. Treatments destroy the tiny vessels, making the red spot disappear. Treatments include:

Liquid nitrogen: A blast of icy cold air freezes the vessels. Often a blister develops the next day and can leave a lightened spot.

Electrocautery: A zap of electricity burns the vessels. It can sometimes leave a tiny scar.

Laser: The blood in the vessels absorbs a blast of light energy, exploding the tiny vessels and removing the spot. The ruptured vessel can cause a bruise that lasts for weeks.

All three methods are effective at removing the red spots, although each hurts a little and each usually requires multiple treatments. The more destructive the treatment, the more likely it is to work the first time, but the more likely it is to leave a scar.

It can be difficult to determine if a red spot on your skin is a harmless cherry angioma or if it is a skin cancer. If you have spots that are changing, bleeding, or multiplying quickly, or if you have any concerns, then you should see a physician.

Photo: Bensonkua (flickr)

I love my iPhone. (No, that’s not me in the photo.)

My iPhone is teeming with apps that help me get through my day (like Doodle Jump for instance). An emerging iPhone trend is the development of apps that diagnose and treat diseases. For example, there is the stethoscope app to help diagnose heart murmurs. In dermatology, there is an app designed to treat acne.

We know that specific wavelengths of light can have medicinal effects such as killing bacteria (red light) and reducing inflammation (blue light). This app produces light at those wavelengths to treat acne. The claim is that by holding the iPhone to your face, the light produced from the app will treat your acne.

Although it scores a 10 on 10 in the coolness factor, it scores a 0 on 10 for proof of efficacy. The studies that looked at treating acne with light used much more intense light than an iPhone uses. The studies with more powerful light exposed faces for 60 minutes every week, which is about 8 minutes on each side every day. Even then, light treatments for acne have not been shown to be consistently better than standard acne treatments such as antibiotics and tretinoin.

So does the acne app work? Well, there are no studies to tell us. Given that the light intensity is low and that most people would not do the treatment — try holding your phone for 2-5 minutes on each side of your face every day for months — I doubt it works.

Acne is common and naturally gets better and worse at times no matter what you do. It is unfortunate that products like this are sold that do not have any proof that they work. There will be people who buy this app and believe that it helped them, (“My acne was clear in just THREE DAYS!”) but the two bucks is better spent on Doodle Jump.

See also:

Can an iPhone App Clear Up Your Acne?

In Light and Heat, Gadgets Claim to Fight Acne

Better Skin to the Touch?

Can You Treat Acne With an iPhone App?

A study to determine the effect of combination blue (415 nm) and near-infrared (830 nm) light-emitting diode (LED) therapy for moderate acne vulgaris.

Photo: Aye Shamus (flickr)

Do you love your morning coffee? Do you love to exercise? Well, so do I. Here’s another reason why we should keep it up: caffeine and exercise might reduce the risk of skin cancer.

A laboratory study of mice found that caffeine and exercise boosted the elimination of ultraviolet light (UV) damaged cells. Disposal of these damaged cells before they can grow reduces the risk of a skin cancer developing.

The study compared the effects of caffeine, exercise, and the combination of both in three groups of hairless mice. Hairless or nude mice are particularly vulnerable to ultraviolet light radiation and are prone to skin cancer.

One group of mice drank caffeinated water, the equivalent of one to two cups of coffee a day. Another group ran on an exercise wheel, the equivalent of a 2.5 mile jog for us.  A third group drank caffeinated water and ran the wheel. All of the mice were exposed to UV radiation. The rate of elimination of damaged cells was highest in the third group that both drank caffeine and exercised.

A different study found that topical application of caffeine can also help prevent skin cancer. Caffeine applied 30 minutes before UVB exposure inhibited cell DNA damage by 80 percent. In other studies, caffeine has been shown to decrease the risk of breast and liver cancer.

Of course, caffeine and exercise are not a substitute for wearing sunscreen; however, they might justify splurging on a latte today. But please don’t place your Starbucks Venti coffee on the gym treadmill next to me in the morning — that drives me nuts.

Photo: Adria Richards (flickr)

The forest is full of things that make you itchy: poison ivy, poison oak, mosquitoes, chiggers. But for the wise adventurer, the forest also provides a way to heal your itch. The remedy might be found in the beautiful white birch tree.

White birch trees are ubiquitous in cold climates. A photo of the white tree against white snow is iconic of New England winters. A bark extract called Betulin (a terpene like tea tree oil) has been shown in animal studies to be antimicrobial, anti-inflammatory, and to aid in wound healing. Research presented at the annual congress of the European Academy of Dermatology and Venerology showed that a cream containing betulin significantly reduced itching in red, irritated skin in psoriasis and eczema patients.

The study is only preliminary, and betulin will need to be tested in rigorous trials to see if the extract makes a cream much better than placebo cream; however, betulin is already available in creams in Europe.

So how do you get the extract out of the bark if you’re  itchy while hiking in a forest? I’ll wait for Bear Grylls to show us on a future episode of Man Vs. Wild. No doubt a fire and half a plastic bottle will be needed.

Photo: Nicolas T