Efficacy and safety of photodynamic therapy for vaginal intraepithelial neoplasia: A systematic review and meta-analysis.

[OBJECTIVE] Vaginal Intraepithelial Neoplasia (VaIN) is a precancerous condition that can progress to vaginal cancer if untreated. Photodynamic Therapy (PDT), recognized for its minimally invasive nature and favorable side effect profile, is increasingly employed for VaIN treatment; however, comprehensive evidence synthesis on its efficacy and safety remains limited. This study aims to comprehensively evaluate the efficacy and safety of 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) in treating VaIN.

[METHODS] We systematically searched PubMed, Embase, Web of Science, and Cochrane Library databases for studies evaluating PDT efficacy in VaIN. Primary outcomes were complete response (CR) rate and HPV clearance rate; secondary outcomes included recurrence rate and adverse events (AE). Meta-analysis was performed using Stata 18.0.

[RESULTS] Nine trials (421 patients) were included. Pooled outcomes: 6-month CR:87% (95% CI: 78%-94%), 12-month CR:84% (95% CI:76%-91%); 6-month HPV clearance:61% (95% CI:55%-66%), 12-month:73% (95% CI:67%-78%); 6-month HPV16/18 clearance:71% (95% CI:61%-80%), 12-month:76% (95% CI:63%-88%); 6-month recurrence:4% (95% CI:2%-8%), 12-month:7% (95% CI:0%-24%); AEs: Increased vaginal discharge (20%, 95% CI: 8%-36%), itching (25%, 95% CI: 1%-62%), burning sensation (23%, 95% CI: 1%-57%), abdominal pain (7%, 95% CI: 0%-21%), and mild vaginal bleeding (0%, 95% CI: 0%-3%). No serious AEs.

[CONCLUSION] ALA-PDT demonstrates high efficacy and favorable safety in treating VaIN. However, as current evidence primarily stems from single-arm studies, future high-quality multicenter randomized controlled trials are essential to confirm these findings and directly compare ALA-PDT with standard therapies.