Abstract LB-337: Adipose inflammation and the risk of benign and malignant breast disease in African American women

Abstract

Abstract Introduction: Obesity is associated with an increased breast cancer (BrCa) incidence. Adipose inflammation, marked by crown-like lesions in the breast (CLS-B) or dying adipocytes surrounded by macrophages, has been previously associated with BMI, aromatase expression, and systemic inflammation - all BrCa risk correlates. However, CLS-B has not been well described in normal or pre-malignant tissue, nor ever described in African American women (AAW). Here we examined whether CLS-B is associated with risk of benign breast disease (BBD) and BrCa in AAW, who suffer a higher incidence of breast cancer, poorer breast cancer outcomes, and a higher prevalence of obesity than women of other ethnicities. Methods: We assessed breast biopsies from three age-matched groups including 50 AAW with no history of BBD or BrCa from the Komen Normal Tissue Bank (KTB) and AAW with BBD from our Detroit cohort who developed cancer (55 BBD cases) or did not develop breast cancer (47 BBD controls). Slides were assessed by pathologists (KK, RAF) for CLS-B presence. Associations between tissue type and CLS-B presence among KTB and BBD samples were assessed using chi-square tests. Association between tissue types and CLS-B adjusting for BMI was assessed using the Mantel-Haenszel test. Results: The KTB, BBD controls and BBD cases groups were matched for age, consisted of approximately 15% <45, 43% 45-55, and 42% 55+ year old AAW. Our study of KTB, BBD control and BBD case groups predominately consisted of overweight (22, 17, and 32%, respectively) and obese women (60, 57, and 47%, respectively). Our data show that CLS-B presence is associated with BBD: significantly more BBD biopsies (29/89=32.6%) were CLS-B positive than KTB biopsies (4/44=9.1%; p=0.006). Among BBD biopsies, fewer BBD controls (11/45=24.4%) were CLS-B positive than BBD cases (18/44=40.9%; p=0.159). After controlling for BMI, CLS-B presence showed an increasing trend among KTB, BBD control and BBD case biopsies (p=0.002, see Table). CLS-B presence by study group and BMIKTBBBD controlsBBD casesN (%) with CLS-B presenceN=44N=44N=42BMI<250/8 (0%)1/10 (10.0%)4/9 (44.4%)BMI 25-291/9 (11.1%)1/8 (12.5%)4/13 (30.8%)BMI 30+3/27 (11.1%)9/26 (34.6%)9/20 (45.0%) Conclusions: These findings suggest that CLS-B may serve as an important histological marker of BrCa risk in benign breast biopsies. Our study population exhibited higher rates of obesity than other BBD and CLS-B studies of European American women highlighting the need to include diverse populations in future studies examining BrCa risk. These findings have potential implications for modeling BrCa risk, particularly among AAW, for whom obesity is prevalent. Citation Format: Asra N. Shaik, Katrin Kiavash, Karri Stark, Julie L. Boerner, Julie J. Ruterbusch, Rouba Ali-Fehmi, Michele L. Cote. Adipose inflammation and the risk of benign and malignant breast disease in African American women [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-337.