Neighborhood deprivation and oncotype DX recurrence scores among Black and White women: the interplay between race, place, and tumor biology

Breast cancer mortality disparities have persisted between non-Hispanic Black (NHB) and non-Hispanic White (NHW) women, even among those with prognostically favorable disease. The Oncotype DX Recurrence Score (ODX RS) is a gene expression panel used to identify estrogen receptor (ER)-positive breast cancers with aggressive tumor biology, and prior studies suggest higher scores among Black women and in lower-socioeconomic areas. We examined associations of neighborhood deprivation with ODX RS among 11,377 NHB and NHW women diagnosed with ER-positive breast cancer (stage I-IIIa, ≤3 lymph nodes) between 2010-2017 in the Georgia Cancer Registry. The Neighborhood Deprivation Index (NDI), derived via principal component analysis of American Community Survey block-group data, was assessed in quartiles. Prevalence ratios (PR) and 95% confidence intervals (CI) were estimated for high-risk (≥31) versus low-risk (<18) ODX RS. Living in the most deprived neighborhoods was modestly associated with high-risk ODX RS overall (PR = 1.08, 95% CI 0.90-1.30) and among NHW women (PR = 1.12, 95% CI 0.87-1.44), but not among NHB women (PR = 1.01, 95% CI 0.77-1.33). NHB women in the least deprived neighborhoods had the highest prevalence of high-risk ODX RS relative to NHW women in those neighborhoods (PR = 1.92, 95% CI 1.53-2.41). These findings suggest neighborhood deprivation does not explain racial differences in genomic risk.