Conventional vs. daylight methyl aminolevulinate photodynamic therapy for actinic keratosis of the face and scalp: an intra‐patient, prospective, comparison study in Italy

Daylight photodynamic therapy ( DL ‐ PDT ) with methyl aminolevulinate ( MAL ) is a simplified PDT procedure that was recently shown in a few trials to be effective for grade I actinic keratosis ( AK ), with improved tolerability and reduced time of clinical attendance as compared to conventional PDT (c‐ PDT ). Objective To evaluate the efficacy and tolerability of DL ‐ PDT vs. c‐ PDT with MAL in the treatment of grade I AK on the face and scalp in Italy. Methods Thirty‐five patients with AK s on the face ( n  = 17) or scalp ( n  = 18) were prospectively enrolled in an intra‐patient, left‐right, prospective, comparison study between DL ‐ PDT and c‐ PDT at a single centre between September and October 2013. Weather conditions and outdoor temperature during daylight exposure were recorded for each DL ‐ PDT session. Pain was assessed after the PDT session and local adverse events 2 days after treatment. Lesion response rate was evaluated on both sides at 3 months. AK s with complete regression were followed until 6 months. Patient's preference for either treatment was recorded. Results There was no difference in complete response ( CR ) rate of AK I at 3 months between DL ‐ PDT and c‐ PDT (87% vs. 91%; RR  = 0.96; P  = 0.16). A lower CR rate was observed with DL ‐ PDT than with c‐ PDT for AK II (36% vs. 61%; RR  = 0.58, P  = 0.06) and III (25% vs. 46%; RR  = 0.50, P  = 0.20). Recurrence rate at 6 months was slightly higher for cleared AK I after DL ‐ PDT than after c‐ PDT (17% vs. 12%, RR  = 1.50, P  < 0.05). DL ‐ PDT was associated with lower pain (Δ VAS  = −2.2, P  < 0.01) and reduced severity of local adverse events (Δ LSR  = −1.4, P  < 0.01) than c‐ PDT . Increasing outdoor temperature was associated with the efficacy of DL ‐ PDT and the severity of adverse events. DL ‐ PDT was preferred by 88% of the patients. Conclusion MAL DL‐PDT showed similar efficacy to c‐ PDT in the treatment of AK I of the face/scalp but was less effective than c‐ PDT for AK s II and III . DL ‐ PDT was better tolerated being associated with lower pain and occurrence of fewer adverse events. Clinical response to DL ‐ PDT was significantly moderated by outdoor temperature, increasing at higher temperatures.