Abstract 4341: Regional disparities in time to treatment for breast conserving surgery and mastectomy in women with early-stage breast cancer
Authors: Dankwa-Mullan Irene , Roebuck M Christopher , Tkacz Joseph , George Judy , Reyes Fredy , Arriaga Yull Edwin 
Published: September 2020

Abstract
BACKGROUND:
Although several studies have reported regional differences in type of surgery performed for early-stage breast cancer (ESBCa), no research has examined geographic trends in time from diagnosis to surgical treatment (TtS), a quality measure for early-stage breast cancer care. Given evidence for improved survival outcomes of expedited TtS, we assessed how TtS for both breast conserving surgery (BCS) and mastectomy (MAST) has changed over time within region.
METHODS:
IBM® MarketScan® claims data were used to select women diagnosed with non-metastatic invasive ESBCa from January 2012 to March 2018. Eligibility criteria included: 1) absence of other cancers 2) ≥ 6 months of continuous insurance enrollment pre- and post- diagnosis 3) treatment with BCS or MAST within 6 months. Days elapsed between diagnosis and first surgery was the dependent variable. Region-specific quantile regression models of median TtS were estimated, which included a vector of patient- and community-level covariates.
RESULTS:
A total of 57,299 women met the inclusion criteria. Among those receiving MAST (n=18,825), 11% had neoadjuvant chemotherapy and 40% had adjuvant chemotherapy. In the BCS cohort (n=38,474), 4% had neoadjuvant chemotherapy, 28% had adjuvant chemotherapy, and 25% had adjuvant radiation therapy. As expected, receipt of neoadjuvant chemotherapy prolonged TtS by 116-128 days (p&lt;0.01). From 2012 to 2017, TtS for MAST significantly increased in the South (3.8 days; p&lt;0.01) and West (8.0 days; p&lt;0.01). Women residing in more urban areas waited longer by 21.9 days in the NE (p=0.01) and 14.2 days in the South (p&lt;0.01). For patients in Black communities, TtS for MAST was greater by 20.7 days (p=0.02) in the Midwest (MW) and 57.8 days in the West (p=0.04). Among women living in more Hispanic areas, median TtS for MAST was lower by 43.4 days (p=0.02) in the Northeast (NE), but was higher by 23.0 days (p&lt;0.01) in the West. In all regions except the NE, TtS for BCS significantly (p&lt;0.01) increased from 2012 to 2017 by between 3.0 (MW) to 6.5 days (West). In more urban areas, women in the NE (14.4 days; p&lt;0.01) and West (20.2 days; p=0.03) had longer TtS. In the NE, women in communities with higher densities of Asians (-19.2 days; p=0.01), Blacks (-20.0 days; p=0.04) and Hispanics (-24.3 days; p=0.05) experienced shorter wait times. However, women from more Hispanic communities in the South had longer TtS for BCS by 6.7 days (p=0.02).
CONCLUSIONS:
Understanding these geographical variations is important to identify potential region-specific and community-level factors influencing time to primary surgery in order to address healthcare inequalities in breast cancer treatment quality. These findings call for policy attention in areas where surgical delays that potentially impact outcomes could be addressed.
Citation Format: Irene Dankwa-Mullan, M Christopher Roebuck, Joseph Tkacz, Judy George, Fredy Reyes, Yull Edwin Arriaga. Regional disparities in time to treatment for breast conserving surgery and mastectomy in women with early-stage breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4341.