Background: Although incidence of breast cancer is higher among white females, mortality rates remain higher among black women. This disparity has widened despite improved breast cancer survival rates over time. The widening gap in black-white mortality for breast cancer may be related to differences in tumor biology, treatments received and access to care. The objective of this study was to assess racial disparities in breast cancer diagnosis-to-treatment waiting times in South Carolina (SC).

Methods: Data for this analysis includes all female breast cancer cases in SC from 2002-2009 derived from linked files from the SC Central Cancer Registry and Office of Revenue and Fiscal Affairs (who maintains the administrative medical claims data for the South Carolina Public Employee Benefits plan and Medicaid). The main outcome variable was diagnosis-to-treatment time (overall and by cancer treatment type) which was defined as the interval between the date of diagnosis and the date of any first course of treatment or the date of receipt of breast cancer-related surgery, radiation, chemotherapy, and hormonal therapy. The main exposure variable was patient race (white vs black). Students' t test with a significance level of 0.05 was used to assess the difference in diagnosis-to-treatment time by patient race.

Results: A total of 1611 breast cancer patients including 1205 white and 406 black females were reported in the study period. There was a consistent increase in the mean number of diagnosis to receipt of first course of treatment among blacks compared to whites overall (22.7 vs 18.4); from diagnosis to surgery (27.2 vs 23.1); from diagnosis to radiation therapy (142.2 vs 122.8 radiation); from diagnosis to chemotherapy (65.5 vs 62.3); from diagnosis to hormonal therapy (148.7 vs 85.3). There was also a consistent increase in the median number of days (18 vs 15; 18 vs 15; 140 vs 91; 56 vs 52; and 136 vs 115) from diagnosis to receipt of first course of treatment overall, and by type (surgery, radiation, chemotherapy and hormonal therapy respectively) among blacks compared to whites. This difference was statistically significant for time to any first course of treatment overall (p: <0.01) and by time from diagnosis to radiotherapy (<0.01).

Conclusions: Black females experience consistently longer waiting times from diagnosis to treatment (overall and by all subtypes of treatments) than their white counterparts. Further exploration is needed to know the reasons why black females have persistent increase in diagnosis to treatment wait times and particular attention should be placed on reduction of the diagnosis to treatment wait times in an attempt to reduce already existing racial disparities in breast cancer outcomes among Blacks and Whites.

Citation Format: Oluwole Adeyemi Babatunde, Swann Arp Adams, Jan Eberth, Erica Sercy, James Hebert. Racial Disparities in Breast Cancer Diagnosis-to-treatment Waiting Times in South Carolina. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr C20.