Abstract C78: Pre-diagnostic journey of women with breast cancer and disparities in stage at diagnosis in Namibia: The African Breast Cancer–Disparities in Outcomes (ABC-DO) Cohort Study
Authors: Togawa Kayo , McKenzie Fiona , Zietsman Annelle , Silva Isabel dos Santos , McCormack Valerie 
Published: February 2019

Purpose: Breast cancer survival rates in sub-Saharan Africa (SSA) are low and the reasons therefor partly involve advanced disease at diagnosis. Within the African Breast Cancer – Disparities in Outcomes (ABC-DO) Study, a prospective study of breast cancer survival in multiple SSA settings, we examined spatiotemporal barriers to early presentation and diagnosis related to pre-diagnostic journey of women with breast cancer in the vast Southern African country of Namibia.

Methods: 503 newly diagnosed breast cancer patients who presented at the Windhoek Central Hospital (WCH) in Namibia completed face-to-face interviews between September 2014 and October 2016. Participants were asked about sociodemographic factors, locations of residential home and health care providers, dates of visits to health care providers, and mode of transport. The straight-line distances from home to the first health care provider and the cancer care facility (WCH) were calculated. Clinical data including disease stage were extracted from medical records. Logistic regression models were used to estimate the odds ratios (OR) and corresponding 95% confidence intervals (CI) for late stage disease (stage III or IV) associated with the pre-diagnostic journey of women.

Results: The analytical sample included 498 women, the majority of whom were black (79%), were diagnosed with a late-stage disease (stage III, 41%; stage IV, 15%), and resided outside Windhoek (within Namibia, 70%; outside Namibia, 10%). The mean age at diagnosis was 54 years (standard deviation, 14.7; range, 24–98). The distance from home to the WCH ranged from 0 to 1,643 km (median, 308 km). In unadjusted analyses, a longer distance from home to the WCH was associated with late stage (per 100 km increment: OR, 1.09; 95% CI, 1.04–1.15); however, distance to the first care provider was not statistically significantly associated with disease stage (OR per 100-km increment, 1.06; 95% CI, 0.97–1.17). Unadjusted analyses also showed that being black (vs. non-black: OR, 5.38. 95% CI, 3.30–8.78), longer time taken to travel to the WCH (OR per one-hour increment, 1.06; 95% CI, 1.02–1.10), and travelling by a transport service provided by a cancer association or a hospital (vs. travelling by private cars: OR, 2.71; 95% CI, 1.78–4.11) were associated with late stage whereas age, time interval between the first contact with a health care provider and the first visit to the WCH, and number of health care providers seen before referral to the WCH were not associated with disease stage. In the analysis that adjusted for race/ethnicity, neither travel distance/time from home to the WCH nor transport mode was statistically significantly associated with disease stage.

Conclusions: In the Namibian subset of the ABC-DO Study, the association between a longer travel distance or time to the WCH and late stage of breast cancer at diagnosis appeared to be driven by the association between race/ethnicity and disease stage. The greater odds of late-stage diagnosis associated with the use of patient transport service likely reflect a response to urgent medical needs. The ongoing analysis will further investigate other potential barriers that explain disparities in stage at diagnosis among women in Namibia and other SSA settings.

Citation Format: Kayo Togawa, Fiona McKenzie, Annelle Zietsman, Isabel dos Santos Silva, Valerie McCormack. Pre-diagnostic journey of women with breast cancer and disparities in stage at diagnosis in Namibia: The African Breast Cancer–Disparities in Outcomes (ABC-DO) Cohort Study [abstract]. In: Proceedings of the Tenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2017 Sep 25-28; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2018;27(7 Suppl):Abstract nr C78.