Abstract 1899: Breast density comparison of Hispanic versus Non-Hispanic patients undergoing screening mammograms: Influence of age, parity and breast-feeding
Authors: Prabhakaran Sangeetha , Pankratz Vernon S. , Saline Jennifer L. , Reese Emily J. 
Published: April 2023

Background: Higher mammographic breast density is associated with a 4 to 6-fold increased risk of breast cancer. Some single institution retrospective studies show higher breast densities in Hispanic patients (Oppong et al. Breast J. 2018). The prevalence of breast density based on Hispanic ethnicity has not been studied in large database studies.

Methods: We performed a retrospective review of women &gt; 40 years undergoing screening mammograms from 2016-2022. Patients with prior history of breast cancer were excluded. We reviewed demographic variables such as race, self-reported ethnicity, body mass index (BMI), parity, breastfeeding and menopausal status. Breast density was characterized as predominantly fatty (PF), scattered fibroglandular (SF), heterogeneously dense (HD) and extremely dense (ED). We used Chi-square and Kruskal-Wallace tests to compare breast density across measured variables, and Ordinal Logistic Regression to compare breast density levels between self-declared ethnicity while adjusting for other variables.

Results: 15946 patients were studied; 7317 (46%) identified as Hispanic, the rest non-Hispanic (NH). 6131 (83%) of Hispanics identified as white. Mean age on 1st screening mammogram was 57.64 (SD 7.21). Compared to NH, Hispanics had mean earlier age of 1st mammogram (56.8 vs. 58.3 years), higher BMI (30.5 vs. 28.6) and higher parity (2.53 vs. 1.71). There were significant differences in BI-RADS density categories by Hispanic vs. NH (p&lt;0.001), with differences in PF (20.2% vs. 18.5%), SF (41.7% vs. 39.0%), HD (35.8% vs. 37.2%), and ED (2.3% vs. 5.3%). The ordinal logistic regression model suggests that Hispanics have 17% lower odds than NH of 1 category higher density (OR, 95% CI: 0.83, 0.78-0.88). There were also significant ethnicity differences in age at first exam, BMI, parity, and number of children breast-fed (P&lt;0.001). Adjusting for these ethnicity-associated differences explained the observed differences in density between Hispanic and NH individuals (ORadj, 95% CI: 0.98, 0.92-1.04); adjusting only for BMI served to explain the observed differences in density (ORadj, 95% CI: 0.99, 0.94-1.05).

Conclusions: Hispanics were observed to have a lower age of first screening mammogram, higher BMI, higher parity, and breast-fed children compared to non-Hispanics. On univariate analysis, Hispanics were noted to have lower breast density compared to non-Hispanics, these differences do not persist on multivariate analysis. This suggests that BMI likely plays a predominant role in driving the ethnicity-related differences in breast density noted here. Further research efforts should focus on the influence of BMI and other individual-level factors on mammographic density, with a view towards understanding their potential roles in describing differential ethnicity-specific breast cancer risk.

Citation Format: Sangeetha Prabhakaran, Vernon S. Pankratz, Jennifer L. Saline, Emily J. Reese. Breast density comparison of Hispanic versus Non-Hispanic patients undergoing screening mammograms: Influence of age, parity and breast-feeding [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1899.