The Efficacy and Safety of 5-Aminolevulinic Acid Photodynamic Therapy for Lichen Sclerosus: A Meta Analysis

BACKGROUND: Lichen sclerosus (LS) is a chronic inflammatory dermatosis that occurs mainly in the anogenital area and causes itching, soreness, atrophy and scarring, which may result in burying of the clitoris in females and phimosis in males. Photodynamic therapy (PDT) has been suggested during the past years as an alternative non-invasive treatment for LS, but there is still no meta-analysis to evaluate its efficacy and safety. AIMS: To assess the efficacy and safety of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) for treatment of LS. METHODS: We undertook a meta-analysis using the methodology of the Cochrane Collaboration and the guideline of PRISMA. A systematic literature search was carried out in PubMed, EMBASE, The Cochrane Library, WanFang Data, CBM and CNKI up to 30 June 2020. Randomized controlled trials (RCTs) were compared with ALA-PDT, corticosteroids or tacrolimus ointments for treating LS. The risk of bias for each trial was rated according to the Cochrane Handbook. Risk ratios (RR) with 95% confidence intervals (CI) were utilized to express the comparative outcomes. RESULTS: We included 4 RCTs with a total of 184 participants. The meta-analysis showed ALA-PDT was better than topical ointments in treating LS (total effective rate: RR 1.38 [95% CI 1.19-1.60]). CONCLUSIONS: The current limited evidence supports the efficacy and safety of ALA-PDT in treating LS. The adverse reactions included pain, swelling, redness and exfoliation which would decrease with the continuing sessions of treatment. Further high-qualified RCTs of large samples are necessarily needed.