Cancer risk among participants in the women's interagency HIV study

Background: The HIV epidemic has been associated with an increased incidence of specific cancers. However, less is known about cancers occurring in HIV-infected women than men. Methods: To determine the risk of cancer among HIV-infected and at-risk HIV-uninfected women, cancer incidence data from the Women's Interagency HIV Study (WIHS) were compared with data from the population-based United States Surveillance, Epidemiology, and End Results (SEER) registry. Age- and race-adjusted standardized incidence ratios (SIRs) were computed and exact statistical tests were used to measure significance. Results: Among the 1950 women participants (1554 HIV infected, 391 HIV uninfected, and 5 HIV seroconverters), 48 cancers were diagnosed during study follow-up. Among HIV-infected women, significantly (P < 0.05) increased incidence rates were observed for all cancer types (SIR = 1.9), Kaposi sarcoma (SIR = 213.5), non-Hodgkin lymphoma (NHL) (SIR = 19.0), and lung cancer (SIR = 6.3) when compared with SEER rates. Lung cancer incidence was also elevated (P = 0.07) among the HIV-uninfected women (SIR = 6.9), when compared with SEER rates, and was similar to the SIR for HIV-infected women. While the incidence rate of NHL among HIV-infected women was significantly lower during the era of highly active antiretroviral therapy (HAART) compared with the pre-HAART era (relative risk = 0.15, P = 0.005), the incidence of NHL among HIV-infected WIHS participants remained significantly higher than in the US population (SIR = 6.4, 95% CI = 1.3-15.5). Conclusion: In the HAART era, the higher rates of cancer among HIV-infected women, coupled with increased life expectancy, should lead to more intensive cancer screening and prevention efforts in this population.