Human papillomavirus (HPV) is the most common sexually transmitted infection worldwide. Infection by certain high-risk types of HPV is the major cause of several cancers in men, notably squamous cell carcinoma (SCC) of the anal canal. Rates of anal infection with these strains and the resultant high-grade anal dysplasia and anal cancer are much higher in men who have sex with men (MSM) than in the general population. Co-infection with human immunodeficiency virus (HIV) further amplifies this burden, making the rates of anal SCC in HIV-positive MSM higher than the historic rates of cervical cancer prior to the adoption of routine cervical cytology screening.
Despite these alarming statistics, there are no established protocols for optimal screening and treatment of anal HPV and cancer precursors, nor has there been any widespread rollout of organized screening programs anywhere in Canada. Further, not only does HPV directly cause significant disease in these men, but there is growing epidemiologic evidence that HPV infection may enhance sexual transmission of HIV. These significant knowledge gaps translate into fundamental deficiencies in care for HIV-positive MSM.
The objective of HPV Save is to build upon previous research done by our group on HPV in HIV-positive MSM in Ontario. Our overarching aim is to gain insight into how to best deliver anal cancer screening, treatment, and vaccination programs for MSM, as well as to further characterize the role of HPV in HIV transmission.
We aimed to enroll with approximately 3,000 MSM. If your Pap smear shows precancerous cells, high-grade squamous intraepithelial lesion (HSIL) you will be invited to participate in another study (Treatment Phase) where you will be offered a special anoscopy called High Resolution Anoscopy (HRA). Approximately 300 men will have HSIL cytology and they will be enrolled in the treatment phase of the study. A subset of men whose Pap smear indicates only low grade squamous intraepithelial lesions (LSIL) or whose Pap is normal will also be invited to have HRA. All HRA activities would happen at Toronto General Hospital, since St. Michael’s does not currently have the facilities to do this, and all participants would be re-consented for the treatment phase if they choose to participate.
This study is being led by Dr. Troy Grennan of the BC Centre for Disease Control and Dr. Irv Salit of the University Health Network, and is supported by the CIHR and CTN.