[Photodynamic therapy for the treatment of extramammary Paget's disease]

The usual treatment for extramammary Paget's disease (EMPD) is surgery, but this approach may have grave functional and physical consequences, as well as high recurrence rates. Topical photodynamic therapy (PDT) offers an optional approach for EMPD; it has a high complete response rate and there is no dose restriction. The aim of this study was to evaluate the efficacy and safety of PDT in the treatment of EMPD.

This series of patients was seen at a single centre between 1 December 2005 and 31 December 2010. All patients with histologically confirmed EMPD were included. Patients received two courses of PDT 21 days apart: 3 hours after topical application of methyl aminolevulinic acid emulsion, they underwent illumination with red light (570-670 nm) at a dose of 37 J/cm(2) for 10 minutes. In the event of relapse, a further cycle was given at week 6.

Eight patients (seven female, one male) of a mean age of 69 years were included. After two series of two illuminations, seven patients were in complete clinical remission at 3 months and one patient was in partial remission. Five patients were still in complete clinical remission at 6 months. All patients had relapsed after a mean 8.4 months (4-14 months). The limiting factor appears to be pain occurring during illumination. Patients reported satisfaction with the disappearance of symptoms and a notable improvement in quality of life.

The complete clinical response rate to PDT at month 6, after two series of two illuminations, was equivalent to that for surgery. Although the recurrence rate was high, this treatment may be repeated without functional or physical consequences. PDT resulted in disappearance of pain and improved quality of life.