Randomised trial on treatment of vaginal high-grade squamous intraepithelial lesion: Self-administered vaginal imiquimod and laser vaporisation.

High grade vaginal squamous intraepithelial lesion (HSIL) (or vaginal intraepithelial neoplasia; VAIN) is a rare human papillomavirus (HPV)-related cancer precursor, which is commonly treated with laser vaporisation or other surgical methods to prevent progression to invasion. Vaginal HSIL has a substantial tendency to relapse despite treatment, for which HPV persistence is a known risk factor. Imiquimod is a topically applied immunomodulator and has shown promise in the treatment of high-grade HPV-related genital cancer precursors. The aim of this study was to assess the efficacy and patient compliance of self-administered vaginal imiquimod in comparison to laser vaporisation in the treatment of vaginal HSIL. We recruited 56 women with histological vaginal HSIL into a randomised controlled trial of laser vaporisation and self-administered vaginal imiquimod with follow-up up to 6 months. Follow-up visits included colposcopy, punch biopsies, and cervical or vaginal swabs for HPV genotyping. In per protocol analyses of 26 women in the laser arm and 27 women in the imiquimod arm, 53.8% and 77.8% (p = 0.07), respectively, showed histological regression at the end of the study. No progressions to invasion were detected during the study period. Genotype-specific post-treatment negativity for HPV occurred in 16.7% of the laser group and in 39.1% of the imiquimod group (p = 0.12). Imiquimod had short-term adverse effects, but 93% completed treatment as instructed. We conclude that vaginal imiquimod is an effective treatment for vaginal HSIL and could be considered an alternative to laser vaporisation.