Women infected with the human immunodeficiency virus (HIV) are more likely to have human papillomavirus (HPV) infection that progresses to pre-cancerous cervical lesions, according to a new study.
Previous research indicates that HIV-positive women face an increased risk of HPV infection, precancerous lesions, and cervical cancer as compared with HIV-negative women. Studies show HIV-positive women are up to 8 times more likely to have cervical cancer than HIV-negative women, stated researchers led by Hilary K. Whitham, PhD, MPH, research associate at the University of Minnesota in Minneapolis.
The researchers published their results in Cancer Epidemiology, Biomarkers & Prevention.
Whitham and colleagues set out to determine how the natural history of cervical HPV infection differs by HIV status. They analyzed data from six studies conducted from 1994 to 2010 in Senegal, West Africa, where HIV is endemic to get a better understanding of the way HPV infection progresses, and to compare its progression in HIV-negative and HIV-positive women.
The researchers followed 1,320 women for an average of 2 years, testing them for HPV and cervical abnormalities about every 4 months. At each clinic visit, women were characterized as normal, HPV-positive, or HSIL (HPV-positive with high-grade squamous intraepithelial lesions). HSIL are precancerous lesions that may progress to cervical cancer, if left untreated.
The results show that HIV-positive women had higher rates of progression and lower rates of regression compared with HIV-negative women. HIV-positive women were 2.55 times more likely to have their HPV infection progress to HSIL than HIV-negative women. As HIV affects the immune system, “HPV goes unchecked, replicating quickly and developing abnormal lesions, which can progress to cancer,” said Whitham.
In countries such as Senegal where cervical cancer screening is not widely available, HIV-positive women may benefit from targeted cervical cancer prevention efforts, the researchers noted. “These findings highlight that targeted screening of the high-risk HIV-positive population may provide an important step in cervical cancer prevention,” said Whitham. “These results also highlight that HPV vaccination of young women prior to HIV infection is an important preventive measure.”
She suggested the results can be generalized to women from other similar countries, especially other sub-Saharan African nations with high HIV rates. However, further studies would be required to confirm the findings and to account for behavioral differences between populations such as smoking, birth control use, and age at first sexual activity.
The study is limited, she said, because much of the data predated the widespread use of anti-retroviral therapy. This limited the researchers’ capacity to analyze the effects of those treatments on HPV progression.
However, as HIV-positive women now live longer due to anti-retroviral therapy, they may face further increased risk of cervical cancer due to additional time to acquire HPV and for pre-cancerous lesions to progress to cervical cancer. This highlights the importance of developing cervical cancer prevention strategies in areas where HIV is endemic, Whitham said.