Introduction:
Cervical cancer and its precursor lesions are caused by a persistent infection with oncogenic types of human papillomavirus (hr-HPV)(1, 2). Worldwide, cervical cancer is diagnosed annually in more than 500,000 women(3, 4). Many studies have proven the efficacy and safety of a prophylactic HPV vaccine against the development of cervical intraepithelial neoplasia (CIN)(5). Therefore, cervical cancer (and other HPV-related diseases) are readily preventable with vaccinations.
About 80% of the HPV infections are cleared spontaneously by the body(6). It is not clear why this has not happened in women with a persistent HPV infection. These women are at risk for the development of CIN. Other premalignant conditions caused by a persistent HPV infection are vaginal, vulvar and anal dysplasia(7) and can also lead to cancer.
Different methods are available for the treatment of CIN. The most commonly used method is the Loop Electrosurgical Excision Procedure (LEEP). This procedure enables treatment and provides a reliable histologic interpretation(8). Nevertheless, treatment has been associated with side effects such as hemorrhage, infection, as well as with adverse pregnancy outcomes, such as premature rupture of membranes and premature birth. The risk of adverse pregnancy outcomes occur especially after multiple treatments(9-11).
Data on recurrent disease after treatment vary in the literature. Up to 17% of the women treated for cervical dysplasia can have residual or recurrent dysplasia(12) with repeated treatment as result. Especially adverse pregnancy outcomes are reasons for concern. Most women diagnosed with CIN are at reproductive age (25-40 years). Moreover, women treated for CIN have an increased risk of cervical vagina and vulvar cancer compared to women with normal primary smear test results(13, 14). Furthermore the cost efficiency of HPV vaccines is highly underestimated because adverse obstetrical outcomes, especially prematurity with neonatal morbidity and mortality, are not taken into account(15).
To avoid recurrent disease, the HPV infection should be prevented first. Different prophylactic HPV vaccines have been massively tested in big clinical trials. The vaccines are highly effectives against mainly HPV types 16 and 18. These clinical trials reported no clear therapeutic effect on patients with prior HPV exposure. Nonetheless, there is increasing evidence of an additional vaccine effect after treatment of clinical HPV related anogenital, dermal and oropharyngeal diseases(16-19). We performed a review of the literature with the aim of determining whether vaccination with an HPV vaccine in addition to LEEP treatment is effective in decreasing the recurrence of CIN.