The aim of Mazvita ‘s thesis was to characterize the epidemiology of HIV-related cancers in South Africa in terms of spectrum, prevalence and incidence of cancers in HIV-positive individuals in the era of antiretroviral treatment in South Africa. This was achieved through 3 studies: (i) a probabilistic record linkage study of two IeDEA-SA ART programs providing care for adults and the National Cancer Registry in South Africa, (ii) a cross-sectional analysis of HIV testing patterns among black adult cancer patients attending a tertiary academic oncology unit in Johannesburg and (iii) a chart review of patients with AIDS-Kaposi sarcoma attending a tertiary academic oncology unit in Pretoria. She found that ascertainment of cancer in HIV cohorts is incomplete, and probabilistic record linkage is both feasible and essential for cancer ascertainment. The prevalence of cancer among HIV patients was 4%. Incidence of cancer in HIV-positive South Africans in the era of potent ART was high (overall incidence rate of 1,315/100,000 pys (95% CI 1,225-1,410)), particularly for AIDS-defining cancers and infection-related cancers. She recommended a systematic approach to cancer surveillance in HIV-positive people and the exploration and implementation of known cancer-specific prevention strategies in the HIV population. Among black adult cancer patients in Johannesburg, 33.7% tested positive for HIV; and over a third of those who were positive were unaware of their HIV status. She therefore recommended routine opt-out HIV testing for cancer patients. Among AIDS-KS patients in Pretoria, survival has improved in recent years as more patients access appropriate ART, chemotherapy and radiation therapy. Mazvita currently works as the project manager and epidemiologist for the South African HIV Cancer Match Study, which is an IeDEA-SA supported national HIV-cancer record linkage study, at the National Cancer Registry, National Health Laboratory Service.