Red Light Photodynamic Therapy Sets Evidence-based Standard for Superficial BCC

In a recent Dermatology Times Expert Perspectives custom video series, Todd Schlesinger, MD, a dermatologist, Mohs surgeon, and clinical trialist at Epiphany Dermatology in South Carolina, discussed the evolving evidence base supporting red light–activated photodynamic therapy (PDT) with 10% aminolevulinic acid (ALA) gel and how clinicians should interpret these data in practice.

Schlesinger emphasized that, while blue light PDT has been widely used in dermatology, particularly for actinic keratosis, robust data supporting its use in sBCC are limited. “We don’t really have as much data for blue light,” he said, noting that much of the existing experience is anecdotal. In contrast, red light PDT now has support from a randomized, double-blind, placebo-controlled study evaluating red light plus 10% ALA gel in a sufficiently large population of patients with sBCC.

“I think that really is going to have to define and set the standard for the data,” Schlesinger said. He explained that red light was selected primarily because of its depth of penetration, which allows energy delivery beyond the epidermis and into the dermis. “That depth being able to penetrate through the epidermis, the dermis, and a little bit into the subcutaneous tissue would make sure that there’s enough energy at the dermal-epidermal junction to effectively treat superficial basal cell carcinoma,” he noted.

When asked how he advises colleagues choosing between light sources, Schlesinger was direct. “I’m going to say red light because the data is there,” he said. “We’ve got the data to support that now.” While future studies could potentially expand the role of blue light, Schlesinger stressed that current decision-making should be guided by available evidence rather than theoretical considerations.

Patient selection also plays a critical role. Based on existing data, appropriate candidates include patients with biopsy-confirmed sBCC located on the trunk or extremities, including lesions up to 2 to 3 cm in size. These are cases that might otherwise be treated surgically, but where patients prefer a non-surgical approach. Practical considerations include access to the treatment site, availability of red light, and absence of contraindications such as significant photosensitivity.

Finally, Schlesinger highlighted the importance of biopsy confirmation before treatment. “We want to make sure that it is a superficial basal cell carcinoma, because that’s where we have the data,” he said, adding that more aggressive subtypes or recurrent tumors are not appropriate candidates for PDT.

Watch more from the series here