Non-melanoma Skin Cancer: An Epidemic

Non-melanoma skin cancer primarily encompasses two types of skin cancer: basal cell carcinoma and squamous cell carcinoma. Basal cell carcinoma (BCC) is the most common type of skin cancer, and it outnumbers squamous cell carcinoma (SCC) by about a ratio of 3 to 1. Recent estimates suggest that 2 million Americans develop over 3.5 million non-melanoma skin cancers each year. This is a fairly staggering statistic when you consider that the next highest cancer incidence is not even 10% of this figure – lung cancer (222,520). Non-melanoma skin cancer represents an epidemic in the United States that continues to grow and add to healthcare costs.

So why is this epidemic not highlighted by the media? Most likely this is a result of the low mortality from non-melanoma skin cancer. Basal cell carcinomas very rarely metastasize. Cutaneous squamous cell carcinomas do have a higher rate of metastasis than BCC, but their metastatic rate is still astoundingly low. Melanoma, breast cancer, and lung cancer have significantly higher mortality rates; and thus, more media attention is directed towards them. This lack of mainstream attention given to non-melanoma skin cancer can unfortunately lead to people trivializing their diagnosis. As a result, these cancers may go long times without diagnosis and treatment and can lead to significant cosmetic disfigurement.

To prevent cosmetic disfigurement from non-melanoma skin cancer, it is important to see a fellowship-trained Mohs surgeon. These physicians are board-certified dermatologists who complete an additional year of training dedicated to skin cancer removal and reconstruction. The training of a Mohs surgeon includes pathology (looking at microscope slides). Mohs surgeons also train extensively in reconstructive surgery so that the best cosmetic outcome can be achieved after skin cancer removal.

What are the advantages of Mohs surgery?

1. High cure rates: Mohs surgery delivers the highest cure rate of any skin cancer treatment modality. Primary basal cell carcinomas have a 99% cure rate, and primary squamous cell carcinomas have a 95-98% cure rate. This means that you won’t have to go back to get your cancer treated again.

1. Tissue sparing procedure: Because 100% of the tissue margin is examined with Mohs surgery, the Mohs surgeon can take much smaller margins than when a standard excision is performed. This means that with Mohs, you only need to take 1-2mm of skin around the cancer. With standard excision, this measurement can be 4mm-10mm of normal skin. The result of this is smaller, less noticeable scars.
2. Real-time results: Because the Mohs surgeon acts as the pathologist, it only takes 30 minutes to one hour to know if all the cancer is out or not. This prevents you from having to make several visits to the doctor to completely remove your skin cancer.
3. Precise mapping of tumor: If tumor is still present on the pathology, the Mohs surgeon makes a precise map to pinpoint the exact location of the tumor. This allows for normal tissue to be spared, resulting in higher cure rates and smaller scars.
   

Dr. Brent Spencer is one of only a select group of North Texas Dermatologists who is fellowship-trained in Mohs surgery. His Frisco dermatology office is conveniently located in Frisco off Lebanon and the Dallas North Tollway. Dr. Spencer is the only Frisco dermatologist who is fellowship-trained in the Mohs procedure.

Sunscreens: What you need to know for this summer

Summer is now upon us. With the better weather of summer, people begin to spend more time outdoors. Whether you spend that time at the beach, pool, golf course, or mowing the lawn, there are some helpful hints that you can do to keep your skin healthy and youthful. First off, try to avoid the most intense sunlight of the day that occurs between the hours of 10 AM and 4 PM. Of course, this is not completely realistic for most people; therefore, you need to be able to choose a sunscreen that will adequately protect you.

Sunscreens have been around since the 1940s. You may remember seeing pictures of life guards with a white substance painted on their noses. This was zinc oxide, one of the earliest sunblocking compounds. Throughout the years, scientists have made several advances in developing sunscreens. In the 1950s, the SPF scale was developed. This allowed for scientists to measure the amount of ultraviolet B radiation (UVB) that was being blocked. For the last twenty years, scientists have been working diligently to improve sunscreens' ability to block ultraviolet A radiation (UVA) as well.

What is SPF?

SPF stands for Sun Protection Factor. It is a measure of how much ultraviolet B radiation that is being blocked. They actually determine this by measuring the amount of light required to cause a sunburn. SPF does not measure the amount of ultraviolet A radiation being blocked.

A SPF of 30 means your skin will not burn until it has been exposed to 30 times the amount of solar energy that would normally cause it to burn.

So a higher SPF is better, right?

For the most part, a higher SPF does offer more protection from sunburn. The American Academy of Dermatology currently recommends that you use a sunscreen with a SPF of 30 or higher. The benefit of numbers that are higher than 30 are questionable in regards to UVB blocking. A sunscreen with a SPF of 40 blocks 97.5 % of the UVB radiation that can cause sunburn.

With that being said, you will commonly see products with SPF's of 50, 70, 85, and even 100+ on the market. So, is there any advantage to these products? Possibly. As sunscreen manufacturers have tried to increase their ability to block UVA radiation, a side effect was that the SPF increased with their sunscreens. (Remember SPF has nothing to do with amount of UVA radiation being blocked). For example, Neutrogena's Ultrasheer Sunscreen with Helioplex technology claims very high SPFs. These SPFs rose as Neutrogena improved their sunscreen's ability to block UVA light.

What is the difference between UVB and UVA light?

The letters that you see after "UV" are A, B, and C. These refer to the wavelength of the UV light. UV light is the radiation from the sun that causes damage to your skin. UVC ranges from 100nm to 280nm, and most of UVC is blocked by our ozone layer. UVB ranges from 280nm to 320nm. UVB has been shown to be carcinogenic (causes skin cancer), and UVB causes sunburn. UVA ranges from 320nm to 400nm. UVA has definitely been implicated in photoaging of the skin (wrinkles, sunspots). Now there are several studies suggesting that UVA also has a role in causing skin cancer. UVA is what tanning salons use, as UVA causes tanning of the skin.

So what measures a sunscreen's ability to block UVA?

This is the big question right now. There are several experimental tests that can measure sunscreens' ability to block UVA. PPD (Persistent Pigment Darkening) is a commonly used measure overseas to quantify a UVA blocking. Currently, the FDA in the United States is evaluating a 5 star rating system for UVA protection. The details of this are still being worked out, but expect to see some UVA rating system in the near future on your sunscreen.

I get a rash every time I wear sunscreen, am I allergic?

It is not uncommon for individuals to be allergic to a component of the chemical blocking sunscreens. It is much more rare to be sensitive to a physical blocking sunscreen.

Physical blocking sunscreens have been around for a long time (zinc oxide, titanium dioxide). Think of these acting like a physical barrier (like clothing) between you and the sun. They are usually not absorbed in the skin, and as a result, may be greasier. Physical blocking sunscreens do a very good job at blocking both UVA and UVB radiation, but their popularity has never taken off because of the white residues and greasiness that they have (although this has improved recently with newer sunscreens using nanotechnology).

Chemical blocking sunscreens have not been around as long. Photoallergic reactions (rashes) can occur with them. PABA was an old chemical blocking sunscreen that commonly caused rashes. You do not see it in sunscreens today. More commonly, today's sunscreens have ingredients such as Avobenzone, oxybenzone, homosalate, octocrylene, etc. Any of these can cause a rash. The benefits of chemical blocking sunscreens is that their vehicles tend to be less greasy and they do not leave a residue. The UVA blocking traditionally was not as good as physical sunscreens, but this has been changed with the recent advent of Helioplex and the approval of ecamsule (Mexoryl) in the USA. The UVB blocking of chemical sunscreens is very good.

So what are your recommendations for a good sunscreen?

• First off, find a sunscreen that you like. If you don't like it, you won't wear it. If you don't wear, then there is no benefit.
• In regards to SPF, stick with a sunscreen with a SPF of 30 or higher
• Reapply sunscreen every 2 hours that you are outside.
• If you have sensitive skin, stick with a physical sunscreen. Look at the ingredients. There should be zinc oxide or titanium dioxide and not much more.
• If you hate greasy sunscreens, try one of the spray sunscreens out. These are chemical sunscreens. Even though the instructions state otherwise, I recommend rubbing this sunscreen in after spraying it onto the skin
• Brand selection: Neutrogena Helioplex technology works well at blocking UVA (found in almost all Neutrogena sunscreens. Aveeno (made by the same company as Neutrogena) has the same technology in their Active Photobarrier. La-Roche Posay has Mexoryl which is another good UVA blocker. This is difficult to find (usually at a dermatologist office or CVS pharmacies). Overall, most major brands do a fairly good job; so again, find something you like.
• For the kids, when they are younger than 2, it is probably better to stick with a physical blocker sunscreen. Blue Lizard is a good brand and so is Aveeno. For children younger than 6 months of age, I would not recommend sunscreen. These young children should be kept out of the direct sunlight and be protected with clothing.
• Amount of sunscreen: think of it like this, it take a shot glass of sunscreen to cover your entire body. If a tube of sunscreen is lasting you the entire summer, you probably are not using enough.

Finally, if you have any doubts about sunscreen selection, contact your local dermatologist. The ultimate goal here is to prevent skin cancer. If you think you have skin cancer, again, contact your dermatologist.

Welcome to our new blog!

Howdy folks!

Welcome to the new blog for the Dermatology & Skin Surgery Institute of North Texas. In the coming weeks, I will post relevant articles about skin, diseases of the skin, skin care, cosmetic products, lasers, and much more. My goal is to give the public a credible blog where you can get trusted information about skin care.

There are so many skin care products and skin care gimmicks out there today. It is really hard to sort which ones really work and which ones are a waste of your money and time. Through this blog, I will try to present scientific evidence (or point out the lack of evidence) for several products. Hopefully, this will help you make more informed decisions as you care for your skin.

If you like what you see, please refer your friends to this site.