Photodynamic Therapy (PDT) to Treat Actinic Keratoses: What to Expect

When is cancer not cancer? When it’s precancer, also known as actinic keratosis (AK). Fortunately, you can tackle AK before it develops into full-fledged squamous cell carcinomas with a simple light therapy treatment called PDT. Here’s how it works.

Summer is here, which means the sun is out, and we get to enjoy all the outdoor activities in and around Salt Lake City, Utah. But that comes with a major drawback — skin cancer.

When the sun hits your skin, its ultraviolet rays penetrate the deeper layers and damage your cells, leading to skin cancer. Often, the first sign is actinic keratosis (AK), a precancerous skin condition that can turn into full-fledged cancer if you don’t treat it.

The best way to do that is with photodynamic therapy (PDT). Dr. Robert Topham and our team at Holladay Dermatology & Aesthetics help Utahns eliminate AKs and keep their skin safe all year using the advanced technology behind PDT. Here’s a little background on AK and what you can expect when you come for a PDT treatment.

What you need to know about actinic keratosis

Athletes, coaches, farmers, construction workers, hikers, beachgoers, and others who spend a lot of time outdoors are prime targets for actinic keratosis, a common form of precancer on the skin. These folks soak in the sun’s harmful UV rays as a side effect of their work or hobby, but sun worshippers invite the cancer-causing beams with open arms. And you’re not off the hook if you choose tanning beds over the real deal — those electric rays do the same damage.

AKs are small lesions that appear on the areas of your skin most often exposed to sunlight, so your arms, legs, scalp, face, shoulders, etc. Some AKs are flesh-colored, others are dark brown, white, pink, or even red. You may notice a textural difference compared to healthy skin, as AKs are often raised, rough, or scaly.

Anyone can get AKs, but if you have light skin, blonde hair, and blue or green eyes, you’re more vulnerable than others. Older folks have a higher risk, as well.

Only 5%-10% of AKs turn into cancer, but don’t let that lull you into a false sense of security because the majority of squamous cell carcinomas (SCC) originated as AK lesions. Although AK and SCC are highly treatable, like all cancers, they're much more difficult to get rid of after they progress into the deeper layers of your skin.

How photodynamic therapy treats AK

Dr. Topham uses photodynamic therapy to treat actinic keratosis because it’s one of the most effective ways to eliminate the problem. The treatment is quick and simple, but the science behind it is more complicated.

First, we apply a photosensitizing gel called aminolevulinic acid (ALA); specifically, we use the Ameluz® brand, containing ALA hydrochloride, 10%. The Ameluz triggers a series of events, starting with a conversion to protoporphyrin IX (PpIX), a protein in your cells that can disrupt the AK lesion’s surface. Your body naturally makes PpIX, but the Ameluz accelerates and increases production.

This topical solution makes your AK more sensitive to light, which brings us to the next step in the treatment. Dr. Topham uses BF-RhodoLED®, a special red light with a wavelength of 635 nm, to activate the PpIX and destroy abnormal cells.

And because PpIX contains red fluorescence, we can easily see all the affected AK cells light up when we apply blue light with a wavelength of 410 nm. These specialized lights allow us to monitor your AK and ensure we eliminate all the damaged cells.

What to expect during PDT

Before photodynamic therapy, you should avoid sunlight and tanning beds for at least 48 hours. Also, make sure you let Dr. Topham know about any medications you’re taking, as some can increase sensitivity to sunlight and result in adverse reactions.

During the PDT procedure, we start by clearing your skin of any scabby or crusty lesions. Then we sterilize the area, protect your eyes and healthy skin, and use a dressing to shield the area from premature light activation.

The topical Ameluz is painless but takes about three hours to convert into PpIX. After that incubation period, we remove the occlusion and apply the BF-RhodoLED light to the area. This phase takes only about 10 minutes and is also painless.

After the procedure, you may have some redness, swelling, and skin peeling, and some people experience burning, itching, pain, and blistering at the site, but these side effects usually subside after a few days. You should stay out of the sun and avoid intense light sources for about two days.

If you have any concerns or questions regarding your actinic keratosis diagnosis or photodynamic therapy, please don’t hesitate to contact our office in Holladay, Utah, at 801-272-4408.