Trends in Racial and Age Disparities in Definitive Local Therapy of Early-Stage Breast Cancer

Abstract

Guidelines recommend breast-conserving surgery (BCS) with radiation or mastectomy for definitive local therapy of stage I/II breast cancers. We assessed receipt of definitive local therapy for early-stage breast cancer by race/ethnicity and age and examined trends over time. We calculated rates of definitive local therapy (mastectomy or BCS with radiation) for 375,547 adult women with stage I or II breast cancer diagnosed during 1988 to 2004 using Surveillance, Epidemiology, and End Results registry data. We assessed the probability of definitive local therapy and trends over time using multivariate logistic regression. Overall, 85.8% of women had definitive local therapy. As mastectomy rates decreased (76.5% in 1988 to 38.0% in 2004; P < .001), definitive local therapy rates also decreased (95.2% in 1988 to 79.2% in 2004; P < .001). In adjusted analyses, rates of definitive local therapy were modestly lower for black and Hispanic (v white) women and higher for Asian women. Differences for black and Asian women were stable over time (P = .61 and P = .35 for interaction), but increased for Hispanic women (P = .0003). Although age differences narrowed over time, women older than 70 years and women <or= 60 years had lower rates of definitive local therapy than women 61 to 70 years throughout the study period. As breast conservation has increasingly substituted mastectomy, our findings suggest fewer women are receiving definitive local breast cancer therapy, with persistent disparities for black and Hispanic women as well as women age <or= 60 and older than 70 years. Interventions to assure receipt of radiation after BCS are needed to eliminate these disparities.