Background: The quadrivalent human papillomavirus (HPV) vaccine was recommended for routine vaccination of 11 or 12 year old females with catch-up through age 26 years in 2006. HPV vaccine has high efficacy for preventing diseases associated with vaccine-targeted HPV types in women naïve to HPV. Vaccine Adverse Event Reporting System (VAERS) is a national spontaneous surveillance system of adverse events following vaccination in the
Objectives: To identify and review VAERS reports of invasive and in situ cervical cancer in women immunized with the quadrivalent HPV vaccine.
Methods: A VAERS database search was performed to identify cases of invasive and in situ cervical cancer reported in the United States from January 1, 2006 through April 9, 2009. Medical Dictionary for Regulatory Activities (MedDRA) search terms used were “cervix carcinoma,” “cervix carcinoma stage 0,” “cervix carcinoma stage III,” “carcinoma in situ,” and “cervical dysplasia.” Case inclusion required a clear statement of a cervical carcinoma or carcinoma in situ diagnosis on any screening or diagnostic test after at least one dose of the HPV vaccine. All reports were reviewed by two investigators.
Results: We identified four VAERS reports for MedDRA term “cervix carcinoma,” one for “cervix carcinoma stage 0,” zero for “cervix carcinoma stage III,” three for “carcinoma in situ,” and 53 for “cervical dysplasia.” Of these, three cases of carcinoma in situ and one case of microinvasive cervical cancer met study inclusion criteria. Patients were between 16 and 24 years old; limited data was available on HPV types.
Conclusions: Cases of cervical cancer and precancers are not unexpected in vaccinated women: 30% of cervical cancers are caused by non vaccine-targeted HPV types and women might have been infected with a vaccine-targeted HPV type before vaccination. Cervical cancer screening continues to be important, even for women who have received the HPV vaccine.