Prophylactic human papillomavirus vaccination to prevent recurrence of cervical intraepithelial neoplasia: a meta-analysis

Objective: The aim of this systematic review and meta-analysis was to review evidence supporting the use of prophylactic human papillomavirus (HPV) vaccines to influence the risk of recurrence of cervical intraepithelial neoplasia after surgical treatment.

Methods: A systematic literature search was performed for publications reporting risk of recurrence of cervical intraepithelial neoplasia after surgical treatment in patients receiving HPV vaccination (either in the prophylactic or adjuvant setting). Comprehensive searches of six electronic databases (MEDLINE, Embase, Web of Science, PubMed, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and references of identified studies) from their inceptions were performed (English language only), and hand search reference lists were performed. Two independent reviewers applied inclusion and exclusion criteria to select manuscripts, with differences discussed and agreed by consensus. The literature search was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Results were reported as mean differences or pooled odds ratios (OR) with 95% confidence intervals (95% CI).

Results: A total of 5744 citations were reviewed; 5 studies comprising 2912 patients were selected for the analysis. There were 1338 patients in the vaccinated group and 1574 in the placebo or unvaccinated group. The incidence of histologically confirmed cervical intraepithelial neoplasia 2+ was reduced in the vaccinated compared to the unvaccinated group (OR 0.34, 95% CI 0.21-0.54, p=< 0.00001). The number needed to treat to prevent one recurrence was 27. Both pre-treatment vaccination (OR 0.40, 95% CI 0.21-0.78, p=0.007, number needed to treat - 37) and adjuvant vaccination (OR 0.28, 95% CI 0.14-0.56, p=0.0003, number needed to treat - 30) reduced recurrence rates.

Conclusion: Prophylactic or adjuvant HPV vaccination reduces the risk of recurrent cervical intraepithelial neoplasia 2+. These data support further investigation of its role as an adjuvant to surgical treatment.