Efficacy of ablative fractional laser‐assisted photodynamic therapy with short‐incubation time for the treatment of facial and scalp actinic keratosis: 12‐month follow‐up results of a randomized, prospective, comparative trial

Abstract

BACKGROUND: Photodynamic therapy (PDT) using methyl aminolevulinate (MAL) is an effective first-line treatment for actinic keratosis (AK). Erbium:yttrium-aluminium-garnet (Er:YAG) ablative fractional laser-assisted MAL-PDT (AFL-PDT) has shown significant benefit for the treatment of AK. OBJECTIVES: The objectives of this study were to compare the efficacy, recurrence rate, cosmetic outcome and safety between AFL-PDT with 2 and 3 h of incubation vs. Conventional MAL-PDT in patients with facial and scalp AK. METHODS: This prospective randomized trial initially enrolled 440 facial and scalp AK lesions in 93 patients. Patients were randomly assigned to AFL-PDT with a 2-h incubation time (2h-AFL-PDT), 3h-AFL-PDT and 3h-MAL-PDT. All patients underwent one session of MAL-PDT using a red light-emitting diode lamp at 37 J/cm(2) , and AFL-PDT groups were assigned to pretreatment with Er:YAG AFL. Patients were followed up at 1 week, 3 months and 12 months post treatment. Efficacy, cosmetic outcomes and adverse events were assessed. Finally, 427 facial AK lesions in 88 patients were analysed in this study. RESULTS: Three months after the last treatment session, 3h-AFL-PDT (91.7%) was significantly more effective than 2h-AFL-PDT (76.8%) and 3h-MAL-PDT (65.6%, P < 0.001), and differences in efficacy remained significant at the 12-month follow-up. The recurrence rate was significantly lower for 3h-AFL-PDT (7.5%) than for 3h-MAL-PDT (22.1%) at 12 months (P = 0.002);however, no significant difference was found between 2h-AFL-PDT and 3h-MAL-PDT. No significant difference was found in cosmetic outcomes or safety between the three groups. CONCLUSIONS: We recommend 3h-AFL-PDT rather than classic MAL-PDT or short-incubation AFL-PDT for treating AK.