Prophylactic HPV vaccination after conization: A systematic review and meta-analysis

Human papillomavirus (HPV) vaccination is essential for cervical cancer prevention. However, the value of HPV vaccination in the context excisional treatment of high-grade cervical intraepithelial neoplasia (CIN 3) remains unclear.

In this meta-analysis, three retrospective and three prospective studies, three post-hoc analyses of RCTs and one cancer registry study analysing the effect of pre- or post-conization vaccination (bi- or quadrivalent vaccine) against HPV were included after a systematic review of literature. Random-effect models were prepared to evaluate the influence of vaccination on recurrent CIN 2+.

Primary end point was CIN2+ in every study. The overall study population included 21,059 patients (3,939 vaccinations vs. 17,150 controls). The results showed a significant risk reduction for the development of new high-grade intraepithelial lesions after HPV vaccination (relative risk (RR) 0.41; 95% CI [0.27; 0.64]), independent from HPV type. Due to the heterogeneous study population multiple sub analyses regarding HPV type, age of patients, time of vaccination and follow-up were performed. Age-dependent analysis showed no differences between women under 25 years (RR 0.47 (95%-CI [0.28; 0.80]) and women of higher age (RR 0.52 (95%-CI [0.41; 0.65]). Results for HPV 16/18 positive CIN2+ showed a RR of 0.37 (95% CI [0.17; 0.80]). Overall, the number of women that would have to be vaccinated before or after conization to prevent one case of recurrent CIN 2+ (NNV) is 45.5.

Meta-analysis showed a significant risk reduction of developing recurrent cervical intraepithelial neoplasia after surgical excision and HPV vaccination compared to surgical excision only.