Abstract
Objective: Evaluate the association between neighborhood disadvantage and Oncotype DX score, a surrogate for tumor biology, among a national cohort. Summary Background Data: Women living in disadvantaged neighborhoods have shorter breast cancer (BC) survival, even after accounting for individual-level, tumor, and treatment characteristics. This suggests unaccounted social and biological mechanisms by which neighborhood disadvantage may impact BC survival. Methods: This cross-sectional study included Stage I and II, ER+ /HER2- BC patients with Oncotype DX score data from the National Cancer Database from 2004-2019. Multivariate regression models tested the association of neighborhood-level income on Oncotype DX score controlling for age, race/ethnicity, insurance, clinical stage, and education. Cox regression assessed overall survival. Results: Of the 294,283 total BC patients selected, the majority were non-Hispanic White (n=237,197, 80.6%) with 7.6% non-Hispanic Black (n=22,495) and 4.5% Other (n=13,383). 27.1% (n=79,7254) of the population lived in the most disadvantaged neighborhoods with an annual neighborhood-level income of <$48,000 while 59.62% (n=175,305) lived in neighborhoods with a median-level income of >$48,000. On multivariate analysis controlling for age, race/ethnicity, insurance status, neighborhood-level education, and pathologic stage, patients in disadvantaged neighborhoods had a greater risk of high- versus low-risk Oncotype DX scores compared to those in advantaged neighborhoods [OR=1.04 (1.01-1.07), P =0.0067]. Conclusion and Relevance: This study takes a translational epidemiologic approach to identify that women living in the most disadvantaged neighborhoods have more aggressive tumor biology, as determined by the Oncotype DX score.