Women with HIV are at higher risk of having potentially cancer-causing HPV in their anal canals, raising questions about how best to screen this population.
Because individuals with HIV have higher rates of human papillomavirus (HPV) than the general population, there’s been particular attention given to screening procedures for anal HPV and anal cancer in HIV-positive men. And any woman—HIV positive or not—who has been to a gynecologist has no doubt been given a Pap smear to screen for cervical cancer, usually caused by HPV. But women with HIV have been less likely to be screened for anal cancer even though their risk is as high as 24 times greater than that of women without HIV, according to the authors of a new study examining anal and cervical HPV in Canadian women.
The EVVA cohort study involved 117 women with HIV who were seen at 4 different HIV clinics in Montreal over a period of 2 years. Although they had been diagnosed with HIV anywhere from 5 to 15 years prior, more than three quarters had no detectable viral load. The overwhelmingly majority of the women were immigrants from Africa (44%) and the Caribbean (29%). Only 23% were born in Canada.
Testing revealed that HPV was common among these HIV-positive women, with half having cervical HPV and more than 3 out of 4 (75.3%) harboring anal HPV. The median number of HPV types in the anal canal was 3, with 2 in the cervix. Only 27% of the women said they had ever engaged in anal sex, and almost all said the last time it had occurred was years earlier.
Not only did a significant portion of the study participants have HPV, most had at least 1 high-risk type of HPV (HR-HPV). HR-HPV is specifically linked to the development of cancer. More than half of the women (51.3%) harbored HR-HPV in their anal canal, and 28.7% had it in their cervix. Notably, women born in Canada were more likely to have any kind of anal HR-HPV than women born elsewhere, especially type HPV16. And to a lesser degree, they also were more likely to have cervical HR-HPV than foreign-born women.
The findings of the EVVA cohort study are in line with the findings of other Canadian studies, and its authors offer a possible explanation for why the majority of participants harbored anal HPV despite never having had anal sex: “Recent studies also reported high rates of anal HPV infection in men or women who do not report receptive anal penetration, supporting the notion that infection may occur through partner-assisted or independent autoinoculation through contact with hands, genitals or objects,” they write in their report’s discussion section.
Regarding the finding that Canadian-born women had a greater likelihood of carrying HR-HPV than immigrants now residing in Canada, the authors suggest that clinicians take into account place of birth when evaluating HIV-positive patients for cancer risk. They note that many of their study’s participants were subject to sexual abuse in their native countries, from which they fled. Because many had had limited sexual contact since arriving in Canada, it’s likely that they acquired their infections overseas. This makes the higher incidence of cancer-causing HPV found in Canadian-born women troubling. “The important difference in HPV16 prevalence according to place of birth suggests that women living with HIV may not all carry the same risk of anal cancer and raises the question of whether certain criteria could be used to better target screening,” they write.
Laurie Saloman, MS, is a health writer with more than 20 years of experience working for both consumer and physician-focused publications. She is a graduate of Brandeis University and the Medill School of Journalism at Northwestern University. She lives in New Jersey with her family.