Association between racialized economic segregation and stage at diagnosis for 3 screenable cancers in New York City.

Abstract

Racial and economic segregation can create barriers to timely cancer diagnosis and adversely affect survival. This study examines the association between neighborhood-level segregation, measured by the neighborhood-Index of Concentration at Extremes (n-ICE), and stage at diagnosis (advanced [regional/distant] vs localized) for 3 screenable cancers in New York City. We analyzed 98 449 incident cases (breast, 58 970; cervical, 4790; and colorectal, 34 689) using New York State Cancer Registry data (2008-2019). Census tract-level n-ICE measures of racial and/or income-based economic segregation were calculated. Age-adjusted stage-specific incidence rates and advanced-to-localized incidence rate ratios (IRRs) were measured across n-ICE quartiles. Advanced-to-localized stage IRRs were significantly higher in the most-deprived and/or non-Hispanic Black (NHB)-concentrated areas (Q1) than the most-affluent and/or most non-Hispanic White (NHW)-concentrated areas (Q4) for breast and cervical cancer (breast: n-ICEIncome, IRRQ1 = 0.71 vs IRRQ4 = 0.48; n-ICENHB, IRRQ1 = 0.75 vs IRRQ4 = 0.53; n-ICENHB+Income, IRRQ1 = 0.74 vs IRRQ4 = 0.47; cervical: n-ICEIncome, IRRQ1 = 1.30 vs IRRQ4 = 0.97; n-ICENHB, IRRQ1 = 1.44 vs IRRQ4 = 0.99; n-ICENHB+Income, IRRQ1 = 1.37 vs IRRQ4 = 0.92) (all P-values < .01). Hispanic concentration alone (n-ICEHispanic) was not associated with disparities; however, its combination with economic deprivation was significant in both cancers (breast: n-ICEHispanic+Income, IRRQ1 = 0.70 vs IRRQ4 = 0.47; cervical: n-ICEHispanic+Income, IRRQ1 = 1.31 vs IRRQ4 = 0.93) (all P-values < .01). All racialized-economic segregation measures (n-ICENHB+Income/n-ICEHispanic+Income) showed increasing IRRs with higher segregation for both cancers (all P-trend < .04). No disparities were observed for colorectal cancer. Racialized-economic segregation in New York City was associated with higher advanced-stage diagnoses of breast and cervical cancer but not colorectal cancer. These findings may partially reflect both structural barriers that delay timely diagnosis and the impact of local equity-driven initiatives that broaden colorectal cancer screening access.