PracticalDermatology

Advances in both photosensitizers and light sources have made photodynamic therapy (PDT) the gold standard for treating actinic keratosis (AK), but the dual-phase nature of the procedure, the associated discomfort, and the potential need for multiple sessions require an informed decision.

Sherrif F. Ibrahim, MD, PhD, who practices at Rochester Dermatologic Surgery, and is an assistant professor in the Department of Dermatology at the University of Rochester, takes a reassuring and realistic approach.

“Any way you look at them—clinically, histologically, or genetically—AKs are precursors to squamous cell cancer, which can quickly become deeply invasive, destructive, and potentially fatal. But because AKs are thin and superficial, we have a variety of non-surgical ways to address them and treat them to stop that progression,” he said.

Have you seen an uptick in patients presenting with AKs?

Sherrif F. Ibrahim, MD: “All skin cancer and skin cancer-related conditions are increasing. AKs are the second most common reason why people visit the dermatologist in America (after acne).”

Has access to treatments increased accordingly?

Dr. Ibrahim: “PDT has become a mainstream procedure in our practice. The fact that most private insurers are no longer requiring prior authorizations or prior approval for treatment has eliminated the barrier for many patients. Billing has been simplified to two codes (a J-code plus a CPT-code). Patients need to understand that they will see two charges for their PDT session; one is for the photosensitizer, and one is for the treatment with the light.”

How do you prepare patients for multiple photodynamic therapy sessions?

Dr. Ibrahim: “We typically have a consultation with PDT candidates beforehand and often treat them at the first visit. We make sure that they’re prepared for the recovery period and have cleared their schedules prior to treatment. We then book a follow up in 2-3 months’ time to assess their response and let them know we may or may not retreat at that visit.

The reality is, anyone who is treated for AKs will eventually get more—and the more severe or higher number of AKs that a person has, the more frequently they will need to be treated. But each successive treatment reduces the amount of damage. Once we treat a patient, we see them back in follow up at regular intervals and together determine their need for additional treatments or ongoing maintenance therapy.”

How do you set expectations regarding potential downtime after PDT?

Dr. Ibrahim: “The degree of reaction is tied to the amount of photodamage that they have, so patients with a lot of AKs are going to have a more exuberant response. When someone has a lot of damage, I tell them, ‘You’re going to have a lot of swelling, redness, and mild-to-moderate discomfort. It’s going to feel like a very bad sunburn in the areas that were treated for the first 48 hours. After the first 2 days, the discomfort and redness then turn to a peel, and this can last for up to a week.

Fortunately, subsequent treatments tend to be less uncomfortable for the patient. I like to tell patients that when we get a treatment that is easy for you to tolerate without much response, then we have restored health to your skin and can space out additional treatments over time.”

What is your protocol post procedure?

Dr. Ibrahim: “Patients should avoid daylight for 48 hours, as the sensitizer remains in the skin can be continually activated. Sunscreen is a must, and it should be a physical blocker, not a chemical blocker, because the photosensitizer is activated by visible light, not UV light. We also recommend generous use of moisturizers, such as Vaseline, to keep the treated areas moist, and aloe and anti-inflammatories to soothe discomfort.”

How does PDT compare to other AK treatments?

Dr. Ibrahim: “There’s a good body of literature supporting the fact that in addition to its superb efficacy, PDT has a better aesthetic outcome than other treatments for AKs. Patients often say, ‘my skin looks better than it did before.’ Phototherapy is an in-office administered treatment as opposed to other field treatments that require the patient to apply a cream on their face for six weeks or more. When compared to some of the other treatments, PDT’s duration of red, peeling skin is shorter, and it’s absolutely more cosmetically elegant.”