A controlled trial of photodynamic therapy of actinic keratosis comparing different red light sources

Background: Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) with red light is well established for actinic keratosis (AK). Differences have been observed concerning pain and efficacy rates with different red light sources. Objectives: To compare pain scores, short- and long-term efficacy rates of PDT of multiple AKs when employing different red light sources.. Material and methods: In a controlled trial, 88 patients (310 AK lesions) received ALA-PDT in combination with either visible light (VIS) + water-filtered infrared A (wIRA) light (PhotoDyn (R) 750 (PD750), 580-1400 nm) for 30 min or incoherent light (Waldmann (R) 1200L (Wa1200L), 600-720 nm) for 10-11 min. Followup visits were performed after 1, 3, 6, and 12 months. if there was no complete cure after 1, 3 or 6 months, a second cycle of PDT was performed. Results: Pain scores were significantly lower in patients illuminated with PD750 rather than Wa1200L. Patient complete clearance rates were 85% and 91% after 1 month, 79% and 92% after 3 months, 97% and 92% after 6 months, and 69% and 85% after 12 months in the PD750 and Wa1200L groups, respectively. Lesion complete clearance rates were 94% and 92% after 1 month, 88% and 97% after 3 months, 96% and 95% after 6 months, and 81% and 89% after 12 months in the PD750 and Wa1200L group, respectively. The efficacy rates were not significantly different. Conclusion: A VIS + wIRA light source produced considerably less pain, while efficacy was not much affected in contrast to previously published studies, probably because the illumination time was longer in this study.