RESUMEN
BACKGROUND: Photodynamic therapy (PDT) has been strongly recommended as an excellent alternative treatment for Bowen's disease (BD). However, reported data on 5-aminolevulinic acid-mediated PDT (ALA-PDT) with red light irradiation are limited and the long-term effectiveness remains to be determined, especially in dark-skinned populations. METHODS: Medical records of BD patients who received ALA-PDT with red light irradiation between February 2011 and June 2021 were reviewed and summarized. Univariate and multivariate analyses of clinically relevant variables that may affect treatment outcomes were performed to identify risk predictors. RESULTS: The overall clearance rate of 122 BD lesions was 89.3% with a median follow-up time of 36 months. The correlation between the effectiveness and fluorescence intensity of pre-PDT or PDT sessions was statistically significant after eliminating the interference of confounding factors. All recurrences occurred in the first two years following ALA-PDT. CONCLUSION: ALA-PDT is an effective treatment for BD in the skin of color patients. Well-executed operation and effective pre-treatment are the determinants of effectiveness. Fluorescence intensity of pre-PDT appeared to be a significant predictor of final effectiveness. In addition, two years of follow-up is necessary following ALA-PDT.