Strengthening Health Systems

To better understand the cultural and geographic populations where cervical cancer is most prevalent, this study is using a retrospective chart review of all cervical cancer cases between 2009-2015 in the British Columbia Cancer Registry. Information from this study will be used by the Cervical Cancer Screening Program in British Columbia to understand where efforts should be focused.

It is well established that infection with a high risk genotype of HPV is necessary for cervical cancer to develop. In 2008, HPV vaccination began in British Columbia schools. To determine the efficacy of the vaccine and to determine if there are HPV type replacements and/or cross-protection against non-vaccine HPV types in the population, an assessment of HPV subtypes in BC women in this "post-vaccination era" is required.

Additionally, there is no data on HPV genotype distribution in cervical cancer cases in British Columbia, and little for Canada. Evaluation of HPV genotype distribution in a cohort of invasive cervical cancer cervical cases in BC will allow identification of differences in HPV types between screened and unscreened women. This important information will enable estimates of the incremental impact of HPV vaccination on cervical cancer in screened women. As the BC Cervical Cancer Screening Program (CCSP) considers a shift from cytology to HPV based screening, HPV typing data will provide crucial information for program planning.

Genital warts remain one of the most commonly reported sexually transmitted infections worldwide. HPV is a large family of viruses, some of which are considered high-risk and can lead to the development of cervical cancer, and others are considered low-risk. Some low risk subtypes including types 6 and 11 are associated with causing genital warts. The HPV vaccine administered in British Columbia’s school-based vaccination program offers protection HPV types 6 and 11. This project will determine the incidence of genital wart infections after the introduction of the publicly-funded HPV vaccination program. This will help us to see if the vaccine has had an impact on the rate of infection.

The school-based HPV vaccination program for girls born in 1994 or later was launched in British Columbia in September 2008. Administration of the HPV vaccine for the entire province is tracked at the BC Centre for Disease Control, while all cervical cancer screening & follow-up records are managed at the BC Cancer, Cervical Cancer Screening Program. By linking these data sources, we will evaluate the effectiveness of the HPV vaccination program, and monitor the impact on intermediate endpoints of cervical cancers. From this evaluation, we will be able to determine whether the school based HPV vaccine program reduced the rates of cervical precancerous lesions and describe HPV vaccine effectiveness at a population level.