Epidemiology of Breast Cancer Presentation in Botswana, South Africa, and the United States.

Introduction: This study sought to compare the clinicopathologic features of women with breast cancer presenting in South Africa, Botswana, and the United States (US).

Methods: Breast cancer samples from Botswana (n = 384, 2011-2015), South Africa (n = 475, 2016-2017), and the US (n = 361,353, 2011-2012) were retrospectively reviewed.

Results: The median age of sub-Saharan African women presenting with breast cancer (age 54 in Botswana and South Africa) was younger than that of those in the US (age 61) (P < 0.001). Sub-Saharan women were more likely to present with advanced stage disease than US counterparts (64.7% in Botswana, 63.3% in South Africa, 13% in the US, P < 0.001). Triple negative disease was highest in Botswana (21.3%) compared to South Africa (11.4%) and the US (12.94%) (P < 0.001). Differences in receptor status at presentation among the three cohorts (P < 0.001) were not observed when the cohorts were stratified by ethnicity. Black/multiracial patients in Botswana and the US were the most likely subsets to present with the adverse characteristic of triple negative disease (21.3% and 23.2%, respectively). No correlation was found between HIV and receptor status in the Botswana (P = 0.513) or South African (P = 0.352) cohorts.

Conclusions: Here we report receptor status patterns at presentation in Botswana and South Africa. This study reveals important similarities and differences which may inform policy and provide context for future epidemiologic trends of breast cancer in low- and-middle-income countries particularly in sub-Saharan Africa.