Incomplete efficacy of 5-aminolevulinic acid (5 ALA) photodynamic therapy in the treatment of widespread extramammary Paget's disease.

Photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA) is an effective treatment for several conditions such as Bowen's disease, subsets of basal cell carcinomas and actinic keratosis. Surgical resection is the first-choice therapy for extramammary Paget's disease (EMPD), but extensive resection is highly invasive and recurrences are frequent. We report two cases of genital EMPD treated by PDT with partial efficacy.