Evaluation of photodynamic therapy (PDT) of high-risk cervical low-grade squamous intraepithelial lesions (LSIL) – A single center experience

• This retrospective study demonstrated that ALA PDT was an effective approach for the treatment of high risk cervical LSIL. • Clinical LSIL lesion remission rate was 87.50% at 6 months follow-up and 92.94% at 12 months follow-up, respectively. • HPV negative conversion rate of HPV was 64.47% 6 months follow-up and 80.46% at 12 months follow-up, respectively. High-risk cervical low-grade squamous intraepithelial lesion (LSIL) can progress to invasive cancer if left untreated. This study aims to evaluate the efficacy of 5-aminolevulinic acid mediated photodynamic therapy (ALA PDT) in the treatment of high-risk LSIL. A total of 197 cases (20-69 years old) of high-risk LSIL treated by ALA PDT were retrospectively evaluated. Lesion remission and HPV clearance were evaluated at 6 and 12 months follow-up. The influence of age and number of treatments were analyzed. LSIL lesion remission rates were 87.50% and 92.94% at 6 and 12 months follow-up, respective. HPV negative conversion rates were 64.47% and 80.46% at 6 and 12 months follow-up, respectively. There was no statistical difference between age groups for lesion remission rate and HPV clearance rate (p≥0.4). No statistically significant association between the number of treatment and lesion remission rate or HPV clearance rate. No serious side effects occurred. Topical ALA PDT is effective and safe for the treatment of high-risk LSIL. It is especially suitable for women with fertility requirements and for elderly patients.