HPV Infection and Cervical Cancer in HIV-Positive Women

July 2009–Infections with human papilloma virus (HPV) have been identified as a cause of most cervical cancers. Among HIV-positive women, HPV infection is a particular concern, and cervical cancer is considered an AIDS-defining illness.

There are over a hundred different types of HPV, with some types responsible for causing genital warts (cauliflower-like growths that occur on and around the genital area) and some that can lead to cancer. HPV in women is best diagnosed through a regular pelvic exam and Pap smear. While a pelvic exam allows doctors to carefully check for the presence of genital warts, the Pap smear involves taking a sample of cervical cells to look for evidence of early cancer. Of the 15-20 types of HPV associated with cervical cancer, HPV-16 and HPV-18 are the most dangerous, and responsible for approximately 70 percent of cancers.

Previous studies in India, Taiwan, and Thailand have linked HIV infection to increased incidence and severity of HPV-related abnormalities of cervical cells and to cervical cancer in Asian women. A recent study on the prevalence of HPV infection in HIV-positive women in Rwanda also yielded similar results.¹ Of the 647 HIV-positive women enrolled in the study, 69 percent were infected with HPV, compared with 14 percent of HIV-negative women. Even more worrisome, 46 percent of the HIV-positive women were infected with cancer-causing types of HPV and 35 percent had multiple types of HPV.

Despite the increased risk of HPV infection in HIV-positive women, in Asia few women are routinely screened for cervical cancer. A vaccine exists against HPV-16 and -18, which has demonstrated greater than 90 percent efficacy in preventing infection, but it does not provide protection to those already infected nor is it easily accessible or affordable to most women in the region. Based on the growing number of research studies demonstrating a higher risk of HPV and cervical cancer in HIV-positive women, there is a greater need for HIV treatment programs to integrate Pap smear testing into routine care and to consider the use of HPV vaccines in high HIV prevalence areas.

¹ Singh DK, et al. Human papillomavirus infection and cervical cytology in HIV-infected and HIV-uninfected Rwandan women. Journal of Infectious Diseases. 2009; 199:1851–1861.