Abstract SS1-03: Examining a decade of racial disparity in partial mastectomy and oncoplastic surgery
Authors: Jean Jolie , Jonczyk Michael M. , Homsy Christopher , Naber Stephen , Chatterjee Abhishek 
Published: February 2021

Abstract
BACKGROUND: Breast Conservation Surgery (BCS) includes either partial mastectomy or oncoplastic surgery, of which oncoplastic surgery has become increasingly prevalent. Previous studies have examined BCS rates and post-operative complications, however, no known study has analyzed racial disparity in BCS utilization rates. Understanding racial disparity is crucial to addressing health equality and access to care. Therefore, our study aims to examine racial differences in BCS utilization rates within an 11-year period to determine how these rates have changed over time. METHODS: This retrospective cohort analysis utilized the NSQIP (National Surgical Quality Improvement Program) database to identify women who underwent BCS procedures between 2008-2018. All patients were diagnosed with ductal carcinoma in situ or invasive breast cancer. BCS was further sub-divided into partial mastectomy and oncoplastic surgery. Patient demographics were recorded, and racial utilization trends were analyzed using a Cochran- Armitage test and Index of Disparity analysis, which is a method for summarizing proportional changes within a group’s population and its subgroups. RESULTS: In the 11-year period, 180,700 women underwent a breast cancer resection, of which 46% underwent BCS. Within BCS, 92% underwent a partial mastectomy and 8% received oncoplastic procedures. For both BCS subgroups, Caucasian women held the highest sample size (82%), followed by African Americans (12%), and Asian Americans (5%). Within the total sample size, BCS utilization increased from 38% in 2008 to 53% in 2018. Within the BCS subgroup, the proportion of patients having oncoplastics increased from 3.5% in 2008 to 10% in 2018, leading to a declining proportion of partial mastectomies: 96.5% to 90.0% (all p&lt;0.01). When stratified by race, oncoplastic utilization between 2008 and 2018 increased from 4% to 10% in Asian and Caucasian patients, and 1% to 10% in African American patients (p&lt;0.01). Overall, the racial index of disparity for BCS patients decreased from 17.1% to 9.7%. Interestingly, the index of disparity has remained relatively unchanged for partial mastectomies (1.2% to 0.2%), but significantly decreased in oncoplastics (35% to 1.6%) suggesting an improvement in racial disparities for this surgical option. CONCLUSION: As breast conservation surgery becomes the mainstay for early-staged breast cancer interventions, it is crucial to understand the potential for novel procedures to worsen healthcare inequalities. This study demonstrates promising progress within the field of breast conservation surgery with a decreasing index of disparity among races especially in oncoplastic surgery.
Citation Format: Jolie Jean, Michael M. Jonczyk, Christopher Homsy, Stephen Naber, Abhishek Chatterjee. Examining a decade of racial disparity in partial mastectomy and oncoplastic surgery [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr SS1-03.