Influence of marital status on risk of mortality for 23,493 cases of triple negative breast cancer for four mutually exclusive race/ethnicities.

Abstract

1098 Background: Marital status has been associated with better breast cancer survival. However, breast cancer is a heterogeneous disease and it has not been determined whether marital status is a survival advantage for women with triple negative breast cancer (TNBC) and if this advantage holds for all race/ethnicities. The purpose of this study was to determine if being unmarried resulted in an increased risk of mortality for TNBC for four mutually exclusive race/ethnicities. Methods: We identified 23,493 cases of TNBC from the California Cancer Registry 2000-2014. Marital status at time of diagnosis was defined as: 1) married, 2) single, never married; 3) separated; 4) divorced; 5) widowed. Race/ethnicity was defined as white (n = 13,241), black (n = 2,775), Hispanic (n = 5,059), and Asian/Pacific Islander (API) (n = 2,418). Kaplan-Meier Survival Analysis and Cox Regression were used to assess the risk of mortality associated with marital status using married as the reference category. Marital status was considered a risk for mortality and hazard ratios (HR) and 95% confidence intervals reported if the Wald χ2 was statistically significant (p < 0.05). Models were adjusted for AJCC stage, age, grade, socioeconomic status, and treatment. Separate analyses were conducted for each race/ethnicity. Results: For allraces, single women had statistically significantly worse unadjusted survival (p < 0.05) than married women. However adjusted analyses showed that single (HR = 1.13; 1.01-1.27) and widowed (HR = 1.43; 1.27-1.61) white women had increased mortality when compared with married women. Single (HR = 1.50; 1.14-1.96) and divorced (HR = 1.75; 1.23-2.48) API women had an increased risk of mortality compared with married women. For black and Hispanic women, marital status was not associated with risk of mortality. Conclusions: Being married at the time of diagnosis of TNBC is a survival advantage only for white and API women but not for black and Hispanic women.