Photodynamic Therapy Expands Its Reach Across Skin Conditions

Photodynamic therapy (PDT) is a well-established but continually evolving treatment modality in dermatology. By combining a topically or systemically applied photosensitizer with a specific light source, PDT triggers the production of reactive oxygen species that selectively damage target tissue. This makes it attractive for conditions ranging from precancerous lesions to inflammatory skin diseases — all without incisions or systemic immunosuppression.

This review article, Part II of a continuing medical education series, surveys clinical applications of PDT across a broad spectrum of dermatologic diseases. The authors — specialists from SUNY Downstate, University of Arizona, and Henry Ford Health — synthesize current evidence and organize conditions by strength of supporting data. The highest evidence supports PDT for actinic keratoses, the only FDA-approved indication in the US.

Beyond actinic keratoses, the review documents growing evidence for PDT in basal cell carcinoma, cutaneous squamous cell carcinoma in situ, acne vulgaris, port wine stains, cutaneous infections, photoaging, actinic cheilitis, mycosis fungoides, rosacea, alopecia areata, and extramammary Paget disease. For each condition, the authors describe how PDT should be administered clinically, enabling practitioners to tailor protocols to individual patients.

From a longevity and preventive health standpoint, PDT's applications in photoaging and actinic damage are particularly relevant. Chronic UV-induced skin damage not only affects appearance but signals cumulative cellular DNA stress associated with cancer risk. PDT offers a mechanism to reverse precancerous change and reduce field cancerization, potentially lowering long-term skin cancer burden.

The review does carry caveats: several off-label applications rely on limited or lower-quality evidence, and multiple authors disclosed financial relationships with pharmaceutical companies developing PDT-related products. Readers should weigh recommendations accordingly and await larger randomized trials for emerging indications.