Socioeconomic status and breast cancer treatment

Abstract

Purpose: Evidence suggests substantial disparities in breast cancer survival by socioeconomic status (SES). We examine the extent to which receipt of newer, less invasive, or more effective treatments-a plausible source of disparities in survival-varies by SES among elderly women with early-stage breast cancer.

Methods: Multivariate regression analyses applied to 11,368 women (age 66-90 years) identified from SEER-Medicare as having invasive breast cancer diagnosed in 2006-2009. Socioeconomic status was defined based on Medicaid enrollment and level of poverty of the census tract of residence. All analyses controlled for demographic, clinical health status, spatial, and healthcare system characteristics.

Results: Poor and near-poor women were less likely than high SES women to receive sentinel lymph node biopsy and radiation after breast-conserving surgery (BCS). Poor women were also less likely than near-poor or high SES women to receive any axillary surgery and adjuvant chemotherapy. There were no significant differences in use of aromatase inhibitors (AI) between poor and high SES women. However, near-poor women who initiated hormonal therapy were more likely to rely exclusively on tamoxifen, and less likely to use the more expensive but more effective AI when compared to both poor and high SES women.

Conclusions: Our results indicate that SES disparities in the receipt of treatments for incident breast cancer are both pervasive and substantial. These disparities remained despite women's geographic area of residence and extent of disease, suggesting important gaps in access to effective breast cancer care.

Keywords: Adjuvant and neoadjuvant treatments; Breast cancer; SEER-medicare; Socioeconomic status.