A randomised, double‐blind, placebo‐controlled trial of photodynamic therapy using 5‐aminolaevulinic acid for the treatment of cervical intraepithelial neoplasia

Abstract Photodynamic therapy (PDT) using topical 5‐aminolaevulinic acid (ALA) has been used to treat histologically confirmed cervical intraepithelial neoplasia (CIN‐I and ‐I/II) in a randomised, double‐blind, placebo‐controlled protocol. Fluorescence microscopy revealed that topical application of 3% ALA in Intrasite Gel® to the cervix for 3 hr resulted in the accumulation of protoporphyrin IX in the cervical epithelium. Treatment of CIN with ALA‐PDT was well tolerated, with only 3/12 patients in the PDT arm (0/13 in the placebo arm) reporting any discomfort during illumination. Histologic examination of the treated tissue following loop excision 3 months post‐PDT indicated that 33% of patients had no evidence of CIN, 42% had no change in the grade of their disease, whilst 25% exhibited an apparent progression of disease. In the control group, the respective figures were 31%, 38% and 31%. There was no significant difference in response between the groups receiving ALA‐PDT and those receiving placebo treatment. © 2002 Wiley‐Liss, Inc.