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

Abstract

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. The first patient, a 78-year-old male, suffered from pubic and scrotal Paget's disease for 6 years despite numerous treatments. The second patient, a 78-year-old female, had vulvar involvement for 2 years that was resistant to multiple treatments. The disease was recurrent and chronic with important pruritus and significant impact on the quality of life. Methyl 5-aminolevulinate was applied for 3 h, and irradiation was applied with red light (630 nm) using a total light dose of 37 J/cm(2) for a period of 10 min. The patients were treated every 2 to 4 weeks for a total of at least three treatments. Both patients experienced a partial transient reduction in their symptoms. One patient had a partial transient remission (< 50% reduction of the involved surface), whereas in the other patient, PDT failed to reduce the surface area of the lesions.

A prospective pilot study to evaluate combined topical photodynamic therapy and surgery for extramammary paget's disease

“…Available data suggest that the evidence of the effectiveness of PDT for EMPD is promising, but limited. Particularly, the role of topical ALA‐PDT for the widespread treatment of EMPD still needs to be verified .…”

“…ALA esters (e.g., methyl ester or MAL) have been developed to improve PpIX production in ALA‐PDT, but they do not perform as well in the skin as they do in the bladder because of the barrier effect of the stratum corneum . Nonetheless, topical MAL‐PDT has also been used for the treatment of EMPD although outcomes are not consistent . The complete clinical response rate to MAL PDT is equivalent to that for surgery .…”

Extensive invasive extramammary Paget′s disease: Surgical treatment

“…[14–17] Photodynamic therapy fails to achieve complete remissions especially in larger tumours. [1819] Other options include topical 5-fluorouracil, topical bleomycin, CO 2 -laser, docetaxel, and radiotherapy. [120]…”

Treatment Outcomes of Adjunct and Stand-alone Photodynamic Therapy in Patients With Extramammary Paget Disease: A Literature Review

“…In the adjunctive PDT cohort, 79.2% of patients experienced pain, and in the PDT monotherapy cohort, 13.0% of patients experienced pain. 1,14,24,25 PDTinduced hypopigmentation or hyperpigmentation at lesion sites was also observed in both adjunctive and monotherapy PDT groups, although 1 study did not report the exact numbers. 24 In the adjunct PDT cohort, 5 patients (11.4%) experienced hyperpigmentation or hypopigmentation, and in the PDT monotherapy cohort, 1 patient (1.3%) experienced slight pigmentation.…”