Abstract 3588: Treatment differences are associated with black-white disparities in advanced epithelial ovarian cancer

Abstract

Abstract Background: Racial differences in survival for ovarian cancer are well documented. Previous research suggests that black-white mortality disparities are partially explained by more advanced disease among black women. Whether differences in receipt of guideline recommended care (including both surgery and chemotherapy) also explain mortality differences between black and white women with advanced epithelial ovarian cancer is not known. Methods: Using the Surveillance, Epidemiology, and End Results (SEER) linked to Medicare claims for 1997-2007, we identified a cohort of 4363 women age 65 and older with histologically confirmed stage III or IV epithelial ovarian cancer. We evaluated long-term survival for black and white women in the entire fee-for-service Medicare population, and then in patients matched by propensity score to create two similar cohorts for comparison with Kaplan-Meier analysis. We investigated the association between race, stage, and survival among women who received guideline recommended care and those who received incomplete care. Adjusted analyses were conducted using Cox modeling. Results: Overall, black women with advanced epithelial ovarian cancer were more likely to die than white women; unadjusted hazard ratio (HR):1.29 (95% confidence interval [CI]: 1.12-1.48). Black women were more likely than white women to present with stage 4 disease (40% vs. 32%, p=0.02) and comorbid conditions (55% vs. 36%, p<0.0001). Black women were less likely than white women to receive guideline recommended care (61% vs. 73%, p=0.0001) and women who received incomplete care had lower survival than women who received recommended care, unadjusted HR of 0.27 (95% CI: 0.25-0.29). In multivariable models including demographic factors, stage of disease, comorbidity, and extent of surgery, there was no racial difference in mortality among women who received guideline recommended care, HR for mortality for black women at 1.09 (95% CI: 0.90-1.13) or among women who received incomplete care, HR for black women at 1.15 (0.89-1.39). The survival analysis of patients matched by propensity score showed no difference between white and black women with recommended care (p=0.68) and no racial difference with incomplete care (p=0.87). Conclusions: Differences in receipt of guideline recommended care partially explain black-white mortality disparities among women with advanced epithelial ovarian cancer. Patients who receive incomplete treatment have worse prognosis. Our findings suggest a need to identify and rectify the cause for disparate treatment rates. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3588. doi:1538-7445.AM2012-3588