Cohort Profile: The South African HIV Cancer Match Study (SAM)

Purpose: The South African HIV Cancer Match Study (SAM) is a national cohort of people living with HIV (PLWH). It was created using probabilistic record linkages of routine laboratory records of PWLH retrieved by National Health Laboratory Services (NHLS) and cancer registry data from the National Cancer Registry. SAM aims to study the spectrum and risk of cancer in PLWH in the context of the evolving South African HIV epidemic. The overarching goal of SAM is to inform cancer prevention and control programmes in children and adults living with HIV in the era of antiretroviral treatment in South Africa.Participants: The SAM study is a national cohort of PLWH (both adults and children) who accessed HIV care in public sector facilities from 2004 – 2014 and had HIV diagnostic or monitoring laboratory tests from NHLS.Findings to date: The SAM cohort includes 5 248 648 PLWH; 69% of these are women. The median age at cohort entry is 33.0 years (interquartile range 26.2 - 40.9). Using SAM, we examined national cancer trends in PLWH and the association of different cancers with immunodeficiency. While the risk of Kaposi sarcoma has declined, the risk of conjunctival cancer and HPV-related anogenital cancers (cervical, anal, vulvar, and penile cancers) continues to rise, despite the widespread availability of antiretroviral treatment. Future plans: An update of the SAM cohort to include more recent data is underway. SAM also has the potential to be enriched through record linkage with other laboratory data within the NHLS (such as tuberculosis, diabetes, and lipid profile data), mortality data and socioeconomic data allowing holistic epidemiological research of co-morbidities with HIV. The SAM cohort is a unique resource for research and surveillance of malignancies in PLWH.