Abstract
Background: Crown-like structures in breast adipose tissue (CLS-B), indicative of proinflammatory conditions, are most frequently observed among obese (body mass index, BMI ≥30 kg/m2) women and may contribute to poor prognosis in this group. African-American (AA) women have disproportionately higher rates of obesity than White women, and at least one prior study suggests the prevalence of CLS-B may be higher among AA women. However, most previous studies have examined CLS-B within affected tissues, which may reflect inflammation in the tumor microenvironment, and few have examined the association between CLS-B and clinical outcomes by race. Methods: We examined the presence of CLS-B detected by CD68 immunohistochemistry in normal adjacent breast tissue from a quadrant uninvolved by tumor obtained via mastectomy among 174 African-American women and 168 White women with stage I—III breast cancer diagnosed at Emory University Hospitals (2007—2012). We also investigated associations between CLS-B and other demographic and lifestyle factors at diagnosis (e.g., BMI, smoking status, age at menarche, parity, lactation, menopausal status, hormone replacement therapy use, and family history of breast cancer). Patients were followed for an average of seven years after diagnosis for recurrence and survival. Multivariable Cox proportional hazards models were used to compute hazard ratios (HR) and 95% confidence intervals (CI) for associations between CLS-B presence and progression-free survival (PFS), controlling for BMI and other potential confounders. Results: Median age at diagnosis for both AA and White women was 54 years, with more than 60% postmenopausal among both groups. AA women were more likely than White women to be obese (52% vs. 24%) and have ER- tumors (30% vs. 12%). Presence of any CLS-B was similar between AA (32%) and White (29%) patients. In multivariable models, we did not find any association between CLS-B and race (HR=1.14, 95% CI: 0.72, 1.82) with the only statistically significant factors being BMI (≥30 vs. 18.5-<25 kg/m2: HR=4.36, 95% CI: 2.17, 8.76) and parity (1+ vs. 0 births: HR=0.43, 95% CI: 0.21, 0.91). Over follow-up, 46 breast cancer recurrences and 52 deaths (23 from breast cancer) occurred. Overall, the presence of CLS-B was not associated with PFS (multivariable HR: 0.97, 95% CI: 0.58, 1.62). When examined by race, there was a difference in the direction of the association between CLS-B and PFS among AA women (HR=1.25, 95% CI: 0.64, 2.46) compared to White women (HR=0.75, 95% CI: 0.33, 1.71), although this difference was not statistically significant (P=0.86). Conclusion: Our results show a strong, positive association between BMI and CLS-B in non-tumor tissue and an inverse association with parity. We did not observe a difference in CLS-B presence by race nor did we find CLS-B to be associated with worse progression-free survival, which is in contrast to previous studies that have examined the presence of CLS-B within specimens in close proximity to the tumor.
Citation Format: Aswathy M Cheriyan, Mark E Sherman, Yuan Liu, Keerthi Gogineni, Jiaqi Liu, Jiabei He, Uma Krishnamurti, Ryan Ashiqueali, Jinjing He, Rami Yacoub, Jasmine Miller-Kleinhenz, Lauren E McCullough, Maret L Maliniak. Presence of crown-like structures in breast adipose tissue and clinical outcomes among African-American and White breast cancer patients [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr C074.