Adjuvant human papillomavirus vaccination after excisional treatment for cervical precancer.

Objective: To evaluate whether adjuvant 9-valent human papillomavirus vaccination improves viral clearance and reduces recurrence after excisional treatment for high-grade cervical intraepithelial neoplasia (CIN2+). Materials and Methods: This retrospective cohort study included women aged 18 years and older who underwent loop electrosurgical excision procedure for histologically confirmed CIN2+ between December 2023 and January 2026. Women with pre-treatment human papillomavirus positivity, negative surgical margins, and available post-treatment follow-up data were included. Patients were stratified according to post-treatment vaccination status. The primary outcome was human papillomavirus clearance at 24 months. Secondary outcomes included clearance at 6 and 12 months, persistent infection, time to viral clearance, and CIN2+ recurrence. Multivariable logistic and Cox regression analyses were performed. Results: A total of 666 women were included, of whom 212 (31.8%) received adjuvant vaccination and 454 (68.2%) did not. Clearance of human papillomavirus was higher in vaccinated than in unvaccinated women at 6 months (60.8% vs. 46.3%), 12 months (78.3% vs. 58.8%), and 24 months (87.7% vs. 77.8%). Persistent infection at 24 months was lower in the vaccinated group (12.3% vs. 22.2%). CIN2+ recurrence occurred in 3.8% of vaccinated women and 11.9% of unvaccinated women. Adjuvant vaccination was independently associated with faster viral clearance (adjusted hazard ratio: 2.0, 95% confidence interval: 1.5-2.7, p<0.001). Conclusion: Adjuvant 9-valent human papillomavirus vaccination after excisional treatment was associated with higher viral clearance and lower CIN2+ recurrence.