Cold-knife conization versus photodynamic therapy with topical 5-aminolevulinic acid (5-ALA) in cervical intraepithelial neoplasia (CIN) II with associated human papillomavirus infection: a comparison of preliminary results

Abstract

Background: The optimal treatment of preinvasive cervical lesions is still not clear as all surgical techniques cause substantial cervical stroma destruction with the risk of a possible incompetent cervix. Photodynamic therapy can preserve fertility due to selective tissue destruction. The aim of the present study was to compare the efficacy of cold-knife conization versus photodynamic therapy with topical 5-aminolevulinic acid in eradicating cervical intraepithelial neoplasia (CIN) II and associated HPV infection.

Patients and methods: Eleven HPV-positive non-pregnant women were selected for photodynamic therapy (PDT). To be eligible for this procedure superficial cervical PAP smears as well as colposcopic biopsies performed before therapy had to show CIN II with the lesion involving at least 15% of the cervix and being colposcopically visible. The deep endocervical PAP smear had to show normal endocervical epithelium. The next (following each PDT) 11 HPV-positive women with CIN II treated with cold-knife conization were used as a control group. The cervical sampling for HPV DNA was performed 3 months after conization and PDT. Patients were followed-up for 1 year with cytological smears and colposcopy at the outpatient department of the hospital.

Results: Follow-up at three months revealed that HPV was eradicated by both techniques in 73%. After 12 months follow-up, 100 vs. 91% (conization vs. PDT) of the patients were disease-free. No systemic side-effects and no local necrosis, sloughing or scarring occurred due to PDT. One patient treated with PDT presented with a relapsing suspicious PAP smear and an abnormal white colposcopic lesion after application of acetic acid 6 months post-PDT. A subsequent conization was performed and revealed a CIN I lesion. No statistically significant differences concerning HPV eradication (p > 0.05) and recurrence (p > 0.05) could be observed between the two methods.

Conclusion: The results presented in this study indicate that topical PDT with 5-ALA is in most cases a successful treatment of CIN II with comparable results to cold-knife conization. In contrast to cold-knife conization, PDT causes no substantial cervical stroma destruction with the risk of a possible subsequent incompetent cervix. Also the feasibility of topical PDT on an outpatient basis, the lack of significant post-treatment complications and the cost effectiveness make the topical approach with PDT preferable in selected circumstances. Due to the potential risk of invasive cancer with metastatic spread, patient's selection criteria must be strict and a pretreatment histological examination is obligatory.