Efficacy of 5% imiquimod for the treatment of Vaginal intraepithelial neoplasia-A systematic review of the literature and a meta-analysis

Vaginal intraepithelial neoplasia (VaIN) is an uncommon disease associated with HPV and is considered to be a precursor of vaginal carcinoma. To date, treatment recommendations vary with no universally accepted standard of care as best treatment modality. Nevertheless, 5% imiquimod appears to be a promising, alternative, non-invasive treatment option. To ascertain the efficacy of 5% imiquimod for the treatment of this rare condition, we conducted a systematic review and meta-analysis of the proportion of women who received 5% imiquimod with their complete response, HPV clearance and recurrence rates. A literature search was carried out throughout the PubMed, EMBASE, ClinicalTrials.gov and Cochrane Databases for relevant studies. We computed the summary proportions for complete response, HPV clearance and non-recurrence following administration of 5% imiquimod by random effects meta-analysis. Six articles reporting on 94 patients were included. The summary proportions of women with complete response and HPV clearance were 76.5% (95% CI 59.4-98.5) and 52.5% (95% CI 29.5-93.6) respectively. The summary proportion of women with non-recurrence appeared high (94.3% (95% CI 67.1-132)), yet not significant. Use of 5% imiquimod for the treatment of VaIN is associated with relatively high response rate, satisfactory HPV clearance, whilst the risk for VaIN recurrence appears low.