5-aminolevulinic acid-mediated photodynamic therapy of intraepithelial neoplasia and human papillomavirus of the uterine cervix - A new experimental approach

The aim of this study was to treat patients for ectocervical dysplasia [cer vical intraepithelial neoplasia (CIN) grades 1 and 2] and associated human papilloma virus (HPV) infections with photodynamic therapy (PDT). In 20 pat ients, 5-aminolevulinic acid (5-ALA, 12% w/v) was applied topically with a cervical cap 8 h prior to illumination. A thermal light source (150 W halog en lamp) emitting a broadband red light (total energy: 100 J/cm(2), fluence rate: 90 mW/cm(2)) was used for superficial illumination of the portio. In addition, an Nd:YAG pumped dye laser (652 nm) was used to illuminate the c ervical canal (total energy: 50 J/cm(2), fluence rate: 300 mW/cm(2)). Preli minary results of follow-ups at 1, 3, 6, and 9 months posttherapy showed a cytological improvement in the grading of the PAP smears in 19 patients and the eradication of cervical HPV in 80%. These results demonstrate that ect ocervical dysplasia and associated HPV infections can be treated by PDT.