Kjaer SK, et al. - Researchers monitored the combined incidence of cervical intraepithelial neoplasia (CIN2, CIN3), adenocarcinoma in situ (AIS), and cervical cancer related to human papillomavirus (HPV)16 or HPV18 to assess the long-term effectiveness of the quadrivalent human papillomavirus (qHPV) vaccine. In women, the qHPV vaccine demonstrated continued protection through at least 10 years. A trend for continued protection through 12 years of follow-up was noticed in addition.