Actinic keratoses (Aks) are precancerous growths that develop from prolonged, cumulative sun damage over the course of your lifetime. Approximately 50% of Americans over the age of 50 have actinic keratoses. Aks are the potential precursors of squamous cell carcinoma. It is felt that at least half of the 5 million cases of non-melanoma skin cancer diagnosed each year may either be from AKs or these patients have AKs.

Your chance of an AK developing into a skin cancer is estimated between 10-25%. They are very slow growing. The AK is often felt before it's ever seen. Making its presence known as a rough spot, AKs eventually develop a red to brown color and become scaly. AKs typically develop anywhere from your late 40's on up, becoming more common the older one gets. However, with the advent of tanning beds and increased sun worshipping, I have seen AKs develop on young adults in their early 20's.

Easy Come, Not So Easy Go

AKs come and AKs may seem to go, but they always end up returning if you haven't treated them. That periodic flaking cycle is fairly normal. So don't put off your trip to the dermatologist simply because that area of roughness (present for 6 months) suddenly seems smooth today. The precancerous damage is deep within the epidermis at what is called the basal layer. The superficial scale is simply a symptom of the damage that must be dealt with. Undoubtedly, without treatment the scale will reform over a period of days to weeks.

Who's At Risk?

Anyone can develop sun damage regardless of race. Obviously the lighter your skin tone, the more likely you are to get sun burned and develop AKs. Sun burns lead to cellular DNA damage. Our skin has a repair system to literally cut out the damaged DNA and replace it with new, healthy code. But too much damage just overwhelms the system. Red heads and fair blondes with blue eyes are notorious for developing precancerous sun damage. Anyone with a lifelong history of sun exposure, especially those raised on farms, veterans of WWII who were stationed in the South Pacific, construction workers and basically anyone who spent a lot of time outdoors will likely have AKs. Truck drivers are known to be prone to having actinic damage on the left arm and face from sun exposure next to the window. And while not well known outside the medical community, anyone with immune suppression, especially transplant patients are quite likely to see rapid and early development of actinic damage.

Say Goodbye To Sun Damage

Sun damage is not a good thing. Everybody knows that. But while we all focus upon those early signs of crow's feet, going for healthy skin is the real issue. There have been several fascinating treatments added to the already respectable options for eliminating actinic keratoses. Here are the gold standards as well as the future of actinic therapy.

• Liquid Nitrogen
• 5 Fluorouracil
• Retin A (et al)
• Fluorhydroxyacid Peel
• Levulan Kerastick
• Solaraze
• Celecoxib
• Glycoalkaloids (SunSpot ES)
• Imiquimod
• Laser Resurfacing

LIQUID NITROGEN

This is the traditional or what I call gold standard of actinic keratosis treatment against which I judge all other therapies. Liquid nitrogen is just that. Nitrogen gas that has been condensed under pressure to some terribly low temperature approximately 160 degrees below Celsius. The old time docs used to apply LN2 with a thick Q-Tip. This could take forever if you're a patient covered with AKs. I like the Cry-ac, basically an insulated thermos with a power spray attachment. It makes for rapid therapy for multiple growths. Treating AKs takes some practice; the incredibly cold temperature of the liquid can cause severe dermal damage with scar formation if misused. However, the trained dermatologist understands how to handle this form of therapy. The problem comes when non-dermatologists take up treatment without some experience.

The AK is lightly sprayed with the liquid nitrogen until a very slight pinkness develops around the edges. It's cold and it does sting, but it is quickly over. After the treatment the area may be somewhat pink and puffy. Blistering or weeping of the treated site may also occur. If you absolutely have to, you can deflate the blister at the edges with a sterile needle, but don't pull off the top. Let is heal and dry up. Keep any open areas clean with Polysporin First Aid Antibiotic Ointment. You may see a scab form. An AK treated with liquid nitrogen is often fully healed within 2 weeks.

For those with a plethora of AKs, treatment is done in sessions. It's just impossible to spray a hundred spots at once! But over the course of several weeks treatment can be performed in tolerable sessions to eliminate multiple AKs.

5 FLUOROURACIL

5- fluorouracil is a chemotherapy medication that when applied topically helps destroy sun damaged areas. Known by a variety of names including Efudex and Fluoroplex, 5-FU literally lights up damaged areas. It's one of those therapies I have kept on hand for anyone literally covered with AKs. While effective, it's not an easy treatment plan to tolerate. However, if you have more damaged skin than normal skin showing, this type of therapy may be appropriate for you. 5-FU has become more widely used over the past few years while various medical insurance plans refused to pay for anything else. But the tide is turning and dermatologists are able to select the appropriate therapy for these precancerous lesions.

5- fluorouracil comes as a cream and as well as a liquid in a variety of strengths. 5-FU is applied twice a day for 4-6 weeks. 5-FU will cause only the sun damaged areas of the skin to become beefy red and weepy. This can be painful and may also be surprising at how much invisible sun damage is really present.

The cream is not to be touched by bare hands, so either protective gloves should be worn, or an applicator should be used during application. Being a chemotherapy drug, pregnant women should not be exposed to this medication.

5-FU also increases sun sensitivity during the several weeks of therapy. Care needs to be used during the summer time. I was traditionally taught that the fall and spring were the best times to use this product, in order to keep the patient as comfortable as possible.

All that inflammation needs help to resolve quickly once you've reached your goal. A steroid cream really helps. It often takes about 2 weeks to resolve this inflammation. Remember, you use your steroid cream AFTER you have completed your 4-6 week therapy or else your medication isn't able to fully treat the AKs. A recheck with your doctor at this point works well to determine how well the 5-FU worked. It's difficult to adequately check how well the AKs have been destroyed when the skin is red, weepy and swollen.

All that inflammation has inspired the development of a host of other treatment options for dealing with diffuse damage that are less irritating.

TRETINOIN AND OTHER VITAMIN A CREAMS

There is no question that initially Retin A, and ultimately a host of other topical vitamin A creams such as Tazorac, Renova and Afirm help reduce the effects of sun damage such as blotchy skin discoloration and smooth out fine wrinkle lines. But are they able to fix precancerous changes? Personally, I don't think so. I think they should be utilized to help cut down on the formation of new AKs, as well as help with the most cosmetic concerns associated with photoaging. But I wouldn't rely upon them to eradicate visible precancerous growths. While this form of therapy was being pushed in the late 80's I simply have not found the clinical results convincing.

FLUORHYDROXYACID PEEL

A technique called the fluorhydroxyacid peel has been shown to be very helpful in the treatment of diffuse actinic damage. It incorporates the use of a glycolic acid peel along with the use of 5-FU. The peel is performed as a series of 6-12 in the physician's office. First, a 70% glycolic acid peel is left on the skin for 6 minutes. After it is neutralized with water, a single application of 5% 5-FU cream is applied. I will advance to a 99% concentration of glycolic acid compound peel if the first 6 session do not give adequate results, and will sometimes extend the length of time the glycolic acid is left on, if needed.

The beauty of this procedure is that there is almost no irritation experienced by the patient, and medical journals have shown that results are better than using the 5-FU alone. The procedure is so well tolerated, and the patient's skin look so normal that no one can tell they just had the peel done, until the results begin to show. Unfortunately, if a medical insurance doesn't cover LN2, it probably won't cover the fluorhydroxyacid peel. I have fought with insurance companies and won when it comes to certain high-risk patients.

New therapies are always exciting. They are the culmination of years of research. The levulan kerastick is a 2 step, 2-day photodynamic therapy process meant to treat AKs on the face and scalp. A chemical solution (which is actually the kerastick) is applied to the visible actinic keratoses on day 1. The chemical, aminolevulinic acid HCL (20% strength), binds with the abnormal cellular DNA and makes these cells photosensitive. On day 2 (ideally sometime 14-18 hours after the solution has been applied), the treated areas are exposed to a special light euphemistically called a BLU-U for approximately 16 minutes. Over the period of several days the AKs become dark and dry up, ultimately peeling off. You need to allot 4 weeks to see full resolution of the actinic keratoses and full healing. Approximately 75% of treated AKs should be gone. During the photodynamic portion of the therapy there may be a stinging or burning sensation. I have heard of some cosmetic dermatologists using this therapy in a more general way as a method of chemical peel.

Patients with known light sensitivities such as those with porphyria or lupus may be excluded from this form of therapy.

SOLARAZE

Recently approved (January 2002) by the FDA for use in the U.S., Solaraze Gel is the first prescription topical NSAID (nonsteroidal anti-inflammatory drug) and is approved for treatment of actinic keratoses. This is an entirely new class of therapy. You're familiar with NSAIDS; Advil, Motrin, Naprosyn, Tylenolall are in the NSAID category. Also known by its generic name diclofenac sodium, it is a 3% formulation. This non-greasy gel is applied twice daily for 2-3 months. Anyone with a known allergy to NSAIDs or aspirin should not under go this therapy due to the risk of a cross-reaction. Some of the most commonly reported side effects include peeling, dryness, irritation and contact dermatitis.

CELECOXIB

Wouldn't it be wonderful if we could simply pop a pill and say good bye to precancerous AKs? The University of Alabama made headlines with the announcement of their research into a commonly used arthritis drug, celecoxib, a Cox-2 inhibitor in the treatment of actinic damage. It is known that something in the inflammatory process triggers certain cancers. Cox-2 is an enzyme produced by inflammation as well as precancerous tissue. So it is thought that blocking its formation may stop the formation of further precancerous growths or treat the ones already present. The FDA has already approved Celecoxib in the treatment of some precancerous polyp of the colon. Celecoxib is an oral NSAID and while it is similar to aspirin it does not have the side effects common to aspirin such as stomach upset.

IMIQUIMOD

Known as Aldara, this prescription genital wart therapy has some interesting features. It functions as a stimulator of the immune system, hence the improvement of clearing warts. But evidence is mounting that this product may also be helpful in treating basal cell carcinomas and potentially precancerous growths as well. To date the FDA has not approved this use but research into this cream goes on.

SUNSPOT ES

SunSpot ES Gel contains an extra strength blend of ingredients, including glycoalkaloids, to soften and exfoliate scaly skin patches, called sun spots. You will feel SunSpot ES begin working almost immediately. In as little as four weeks, you will notice healthy revitalized skin. If you have been diagnosed with Actinic Keratosis, as your doctor if SunSpot ES would be an appropriate treatment for you.

LASER RESURFACING

Is there any question that if you burn off the epidermis you'll take all the sun damage with the normal skin, too? I am NOT a proponent of laser resurfacing as a method of treating diffuse actinic damage. There are far too many less invasive therapies currently available. They're much more economical as well as unlikely to leave permanent skin discoloration or scar formation. I would consider this an AK therapy of last resort.

KEEP AN EYE ON IT

If an AK is beginning to itch or bleed, it is possible that squamous cell carcinoma is beginning to form. Another telltale sign is extensive thickening of the AK known as hyperkeratosis. I often consider the possibility of a malignancy if the lesion remains resistant to aggressive treatment. At that point it's time to perform a skin biopsy.

Depending upon the extent of actinic damage (sun damage leading to precancerous skin changes), I will recheck patients anywhere from every 8-12 weeks to just 1-2 times a year. I stress the importance of having a complete skin exam by your dermatologist. Where there's sun damage to cause AKs, there may be a suspicious mole or hidden skin cancers. I usually do this once a year, increasing the frequency depending upon the particular patient.

It's not all about treatment. Prevention is your best defense against actinic damage. While it may not sound glamorous, wear your broad spectrum SPF 30 daily. Get a wide brimmed hat (baseball caps don't count), such as those made by Physician Endorsed and wear sun protective clothing. Use Sun Guard Laundry Treatment UV Protectant. Take the proper steps to protect your children. I can't stress the importance of prevention for children enough. A child is far more susceptible to the cancer forming ultraviolet rays. The 65 year old who presents with their first Aks often had their sun damage in their early childhood years. And if you already have sun damage, get a baseline skin exam from an expert. Know where you stand and don't be shy about discussing the newest advances in treating actinic keratoses. You'll be taking important steps for your preventative skin health.

Thank you for taking the time to read my article. I hope that you have found it informative.

Audrey Kunin, M.D.

(Any topic discussed in this article is not intended as medical advice. If you have a medical concern, please check with your doctor.)

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