Patients with pre-cancerous skin spots may have more luck with light therapy than with standard freezing therapy, according to a new study.
Actinic keratoses are rough, scaly spots that often form on the faces and scalps of fair-complexioned people who have been exposed to a lot of sun. Since they can lead to cancer, removing them quickly and permanently is important.
Cryotherapy is the current standard for treatment. In this process, liquid nitrogen is used to freeze spots and remove them before they can become a problem. An alternative is light therapy, also known as photodynamic therapy, which uses a liquid medication that becomes activated and kills the lesion’s cells when a doctor shines a special light on the spot.
In the new study published in JAMA Dermatology in August, researchers analyzed four prior studies that compared cryotherapy and photodynamic therapy. The studies were conducted on 641 patients with over 2,000 lesions treated with each method. This review of prior research revealed that people who received photodynamic therapy were 14% more likely than cryotherapy patients to see their lesions completely cleared three months later.
As the study’s lead author Dr. Daniel Eisen put it, photodynamic therapy “is associated with better outcomes,” even though freezing has been the go-to for decades. While he doesn’t think photodynamic therapy will replace cryotherapy, he did say it makes a good alternative. People with 20-30 lesions, for instance, would benefit from a treatment like photodynamic therapy that could target all the lesions at once.
Canadian dermatologist Dr. Harvey Lui was not so optimistic about photodynamic therapy in an interview with Healthday. “There are economic barriers, barriers related to the tolerability of the treatment, and barriers because the treatment is time consuming,” he said, adding that it can be difficult to get insurers to cover the therapy. It is, however, covered by Medicare. According to Lui, light therapy can also take hours longer and cause slightly more pain for patients.
Lui suggested applying the medication and having patients expose themselves to sunlight as a cheaper alternative to lengthy light therapy sessions. “We can use sunlight to treat a disease that was caused by sun exposure,” he said.