A population-level evaluation of the effect of antiretroviral therapy on cancer incidence in Kyadondo County, Uganda, 1999-2008

Background: The introduction of antiretroviral therapy (ART) in the United States and Europe has led to changes in the incidence of cancers among HIV-infected persons, including dramatic decreases in Kaposi sarcoma and non-Hodgkin lymphoma, and increases in Hodgkin lymphoma, liver, and anogenital malignancies. We sought to evaluate whether increasing availability of ART is associated with changing cancer incidence in Uganda. Methods: Incident cases of 10 malignancies were identified from Kampala Cancer Registry from 1999 to 2008. ART coverage rates for Uganda were abstracted from the Joint United Nations Program on HIV/ AIDS reports. Negative binomial and Poisson regression modeled the association between ART coverage and age-adjusted cancer incidence. Results: ART coverage in Uganda increased from 0% to 43% from 1999 to 2008. With each 10% increase in ART coverage, incidence of Kaposi sarcoma decreased by 5% [incidence rate ratio (IRR) = 0.95, 95% confidence interval: 0.91 to 0.99, P = 0.02] and stomach cancer decreased by 13% [IRR = 0.87 (95% CI: 0.80 to 0.95), P = 0.002]. Conversely, incidence of non-Hodgkin lymphoma increased by 6% [IRR = 1.06 (95% CI: 1 to 1.12), P = 0.05], liver cancer by 12% [IRR = 1.12 (95% CI: 1.04 to 1.21), P = 0.002], prostate cancer by 5% [IRR = 1.05 (95% CI: 1 to 1.10), P = 0.05], and breast cancer by 5% [IRR = 1.05 (95% CI: 1 to 1.11), P = 0.05]. ART coverage was not associated with incidence of invasive cervical cancer, lung, colon, and Hodgkin disease. These findings were similar when restricted to histologically confirmed cases. Conclusions: Our findings suggest that AIDS-defining malignancies and other malignancies are likely to remain significant public health burdens in sub-Saharan Africa even as ART availability increases.