Photodynamic therapy of high-grade cervical intraepithelial neoplasia with 5-aminolevulinic acid.

Abstract

BACKGROUND AND OBJECTIVES:

To determine the safety and efficacy of 5-aminolevulinic acid (ALA) as a topically applied photosensitizer for photodynamic therapy (PDT) of cervical intraepithelial neoplasia (CIN).

STUDY DESIGNS/MATERIALS AND METHODS:

Forty women, who were at least 18 years old with persistent biopsy-proven CIN 2 and CIN 3 within the previous 3 months of enrollment, underwent PDT in a phase I and II design. Five escalating radiant energies (increments of 25 J/cm(2), beginning at 50-150 J/cm(2)) using a Coherent Dye Model 920 argon pumped dye laser providing light at 630 nm (maximum output 0.8 W) were used to perform PDT with a fixed dose of ALA (200 mg/ml). ALA was placed in a cervical cap fitted to the cervix. After 90 minutes, the cap was removed and the ectocervix was illuminated for 5-16 minutes, depending on the irradiance. Success was defined as the absence of CIN on Pap smear or colposcopic examination at 12-months. Patients were monitored for toxicity.

RESULTS:

Thirty-two women (80%) completed the study with 1 year of follow-up. Sixty percent had CIN 3 and 40% CIN 2. Success rates at 4, 8, and 12 months were 51, 46, and 31%, respectively, and were not light-dose dependent. Three patients progressed from CIN 2 to CIN 3. Toxicity was tolerable and only consisted of spotting, vaginal discharge, mild cramping, and vaginal warmth. There was no apparent dose relationship to toxicity.

CONCLUSIONS:

PDT at this light and ALA dose is well tolerated but has minimal activity in the treatment of CIN 2 and CIN 3. Other doses and schedules of light and ALA or novel photosensitizers may improve efficacy.

• Authors: Kristin A Keefe, Yona Tadir, Bruce Tromberg, Michael Berns, Kathryn Osann, Rasha Hashad, Bradley J Monk
• Journal: Lasers in surgery and medicine (Lasers Surg Med) Vol. 31 Issue 4 Pg. 289-93 ( 2002) ISSN: 0196-8092 [Print] United States
• PMID: 12355576 (Publication Type: Clinical Trial, Clinical Trial, Phase II, Clinical Trial, Phase III, Journal Article, Randomized Controlled Trial, Research Support, U.S. Gov't, P.H.S.)
• Copyright: Copyright 2002 Wiley-Liss, Inc.

Chemical References

• Photosensitizing Agents
• Aminolevulinic Acid

Topics

• Adult
• Aminolevulinic Acid (adverse effects, therapeutic use)
• Female
• Follow-Up Studies
• Humans
• Outcome Assessment, Health Care
• Photochemotherapy (adverse effects)
• Photosensitizing Agents (adverse effects, therapeutic use)
• Severity of Illness Index
• Time Factors
• Uterine Cervical Neoplasms (drug therapy, pathology)
• Uterine Cervical Dysplasia (drug therapy, pathology)