Photodynamic therapy in the treatment of oral leukoplakia: A systematic review

Objective: The aim of the present study was to systematically review the efficacy of photodynamic therapy (PDT) in the management of oral leukoplakia (OLK). Methods: This systematic review aimed to address the following focused question: "Is photodynamic therapy effective in the management of oral leukoplakia?" PubMed/Medline, EMBASE, ISI Web of Knowledge, OVID, CNKI, and WANFANG DATA were searched up to and including June 2018 using different combinations of the following keywords: photodynamic therapy, leukoplakia, oral dysplasia, oral precancers, and oral premalignant lesions. Results: Sixteen studies were included in the present study. A total of 352 patients was included in this review, with age ranging from 20 to 79 years. Photosensitizers used were aminolevulinic acid, Photofrin, methylene blue, and chlorine-e6. Laser wavelength, duration of irradiation, and power density were 420-660 nm, 60-1000 s, and 100-150 mW/cm(2), respectively. On the whole, the rates of complete response and partial response were 32.9% and 43.2%, and the sum was 76.1%. The follow-up period ranged from 1 month to 119 months. The recurrence rate of OLK was 0-60%. Conclusion: PDT appears to be a useful therapeutic strategy in the management of oral leukoplakia as a nonsurgical treatment. Further RCTs with long follow-up period, standardized PDT parameters, and comparing efficacy of PDT with various other therapies are needed to acquire definite conclusions.