Imiquimod for vaginal intraepithelial neoplasia 2-3: A systematic review and meta-analysis

The treatment strategy for vaginal intraepithelial neoplasia (VaIN) 2-3 has not been established. This study aimed to investigate the efficacy of imiquimod in VaIN 2-3.

Electronic databases (PubMed, EMBASE, ClinicalTrials.gov, and Cochrane Central Register of Controlled Trials) were searched from their inception until October 2019 and articles reporting imiquimod treatment for VaIN 2-3 were extracted. Additionally, the clinical records of women with VaIN 2-3 who had been treated with imiquimod in Shizuoka General Hospital from January 2016 to May 2020 were investigated. The data from the systematic search and the data from our hospital were analyzed, and a pooled complete response (CR) rate and response rate of imiquimod treatment for VaIN 2-3 were estimated. As a subgroup analysis, the CR rates and response rates were compared between women with and without a history of hysterectomy, and the rate ratio was calculated.

Five articles described 28 women with VaIN 2-3 who underwent imiquimod treatment, and nine women with VaIN 2-3 were treated with imiquimod in our hospital. The discontinuation of the treatment was required in only one patient of the reported cases. The pooled CR rate and response rate of imiquimod, regardless of a history of hysterectomy, was 0.76 (95% CI, 0.59-0.87) and 0.89 (95% CI, 0.71-0.97), respectively. In the subgroup analysis, the CR rate in patients with hysterectomy was 0.98 (95% CI, 0.11-1.0) and in those without hysterectomy was 0.60 (95% CI, 0.30-0.84), and the rate ratio was 0.83 (95% CI, 0.48-1.19). The pooled response rates with and without a history of hysterectomy were not estimated, and the rate ratio was 0.83 (95% CI, 0.54-1.09).

Imiquimod can be an effective treatment for vaginal intraepithelial neoplasia 2-3.