Abstract 624: A case control study of benign breast disease and breast cancer among indigenous African women

Purpose: To determine the association between benign breast disease (BBD) and breast cancer and if BBD is a mediator of the association between established risk factors and breast cancer among native African women Methods: We analysed data from 5154 women who participated in a case control study (2405 cases and 2749 controls) between March 1998 and December 2014 in three sub Saharan African countries: Nigeria (n= 4233), Uganda (n=477) and Cameroon (n=444). Breast cancer cases aged 18 years and older were enrolled in two tertiary hospitals in the two countries, unselected for age at diagnosis and family history. Controls who were free of breast cancer were enrolled in the same hospitals. Interviews were conducted to obtain data on potential epidemiological risk factors for breast cancer. We determined the association between breast cancer, history of BBD, age at diagnosis and types of BBD using logistic regression, while adjusting for socio-demographic characteristics and established risk factors. In addition, we estimated the proportion of the effects of other established risk factors mediated by BBD in the etiology of breast cancer. Results: Less than a tenth (8.1%, 420) of the study participants reported having a history of BBD, 87 of the 420 reported a biopsy diagnosed BBD. Among breast cancer cases, the proportions of BBD and biopsy-confirmed BBD were 10.4% and 3.8%, respectively, compared to 6.3% and 1.3% among controls (both p Conclusions: Benign breast disease is a risk factor for breast cancer among women in SSA. The mediator role of BBD in the effects of established risk factors on breast cancer risk appears very minimal. Citation Format: BABATUNDE ADEDOKUN, Stella Odedina, Oladosu Ojengbede, Adeyinka Ademola, Temidayo Ogundiran, Dezheng Huo, Olufunmilayo Olopade, Imaria Agwai, Timothy Makumbi, Paul Ndom, Antony Gakwaya. A case control study of benign breast disease and breast cancer among indigenous African women [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 624.