Photodynamic therapy of vulvar intraepithelial neoplasia using 5-aminolevulinic acid

Photodynamic (PDT) therapy is a relatively new technique with unique proper ties that make it attractive for the local treatment: of superficial epithe lial disorders. The objective of this study was to investigate the clinical response of PDT with the photosensitizing agent 5-aminolevulinic acid (5-A LA) in patients with vulvar intraepithelial neoplasia (VIN) grades I to 3. Twenty-five patients with I I I lesions of VIN 1-3 were topically sensitize d with 10 ml of a 20% solution of 5-ALA and treated with 57 cycles of laser light at 635 nm (100 J/cm(2)). Seventy (64%) of the I I I VIN lesions regr essed after various PDT cycles. A complete response was achieved in 13 pati ents (52%) with 27 lesions. All patients with VIN I and mono- and bifocal V IN 2-3 showed complete clearance, However, a complete response could be ach ieved in only 4 (27%) of 15 women with multifocal VIN 2-3, whereas a partia l response was noted in 9 of these patients with a total of 70 lesions, out of which 44 (63%) lesions disappeared. No response was seen in 2 patients with multifocal VIN 3, Histological assessment of the fluorescence-directed biopsies revealed that increased pigmentation and hyperkeratosis of the le sions were associated with low response rates. PDT using 5-ALA represents a n alternative treatment modality for VIN which is easy to perform and has t he advantage of minimal tissue destruction, low side effects and excellent cosmetic results. However, multifocal VIN disease with pigmented and hyperk eratinic lesions remains difficult to treat. (C) 2000 Wiley-Liss, Inc.