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.