Subhedar, Preeti

Abstract Background: There is debate regarding the benefit of breast surgery in women with stage IV breast cancer, especially among those with oligometastatic disease and good response to systemic therapy. Although some retrospective studies have suggested that locoregional therapy may improve survival, this finding has not been universally replicated in randomized controlled trials (RCT) in India, Turkey, and recently the US. To assess need for dissemination of trial results by members of the Alliance/American College of Surgeons Clinical Research Program Dissemination and Implementation (ACS CRP D&I) committee, we sought to determine trends in surgical resection and other therapies for stage IV breast cancer in response to these findings. Methods: The National Cancer Database (NCDB) was queried to identify women diagnosed with clinical stage IV breast cancer of ductal, lobular, or metaplastic histology between 2004-2017. Trends in the rate of women who underwent surgery with breast-conserving surgery (BCS) or mastectomy, radiation, and/or systemic treatments were compared. Possible predictors of breast surgery were examined in univariable and multivariable analysis. Results: We identified 87,331 cases meeting inclusion criteria and assessed demographics for surgery versus no surgery. Of the 87,331 cases, 7,718 (9%) underwent BCS and 17,625 (20%) underwent mastectomy. Rates of breast surgical resection for women with clinically diagnosed stage IV breast cancer rose until 2009, reaching a peak at 37%, followed by a decline to a rate of 18% in 2017 (Table). The largest decline was seen in the hormone receptor positive (HR+) and HER2- subgroup with 71% of patients undergoing surgery in 2007 down to 15% in 2017. Concurrently, the mean number of days between chemotherapy initiation and definitive surgery has been on the rise, ranging from 52 days in 2004 up to 94 days in 2017. In 2004, the rate of systemic therapy alone was slightly more common than locoregional therapy (surgery and/or radiation) with or without systemic therapy (48% vs 37%). By 2017, systemic therapy alone was by far more frequently utilized (69% vs 20%, p<0.001). On multivariable analysis, factors associated with reduced odds of receiving surgery were older age, black race, higher comorbidity index, being uninsured, smaller tumors, lower histologic grade, multiple sites of metastasis, and treatment with chemo-endocrine therapy (all group p values ≤0.001). Factors associated with increased odds of receiving surgery were metaplastic histology, TN subtype, and radiation therapy (all group p values ≤0.001). Conclusions: Rates of surgical resection of the breast primary for stage IV breast cancer have been on the decline in recent years, especially for HR+/HER2- disease, suggesting that providers are responding to the lack of benefit demonstrated in RCTs. Higher rates of surgery in patients with HR-/HER2+ disease and the concurrent rise in the time interval between initiation of systemic therapy and definitive surgical intervention suggest that providers may still be selecting surgery for patients with certain subtypes or those with a durable response to systemic therapy. These areas of continued clinical equipoise could be a target for future studies or de-implementation strategies. OverallHR+/HER2-HER2+TNUnknownSurgery/Total%Surgery/Total%Surgery/Total%Surgery/Total%Surgery/Total%20041189/351334-55-30-50-3420051202/353834-65-35-23-3420061268/375834-54-36-31-3420071571/433636-71-41-32-3620081992/54203754/925926/544820/41491892/52333620092194/592437172/3604883/1525556/106531883/53063520102318/6419361162/331835554/134841352/80144250/9522620112322/6921341220/378932532/144137384/91542186/7762420122238/7110311177/393830587/163536339/85340135/6842020132147/7579281173/423128534/172831334/92536106/6951520142013/8033251086/442825496/185227306/99831125/7551720151805/794323914/434321517/198126288/9962986/6231420161609/819420829/464018459/196823247/10122474/5741320171477/813618722/467815421/190522256/10372578/51615Percent of women with stage IV breast cancer undergoing surgery by year and receptor subtype. Rows containing any number <10 are not reported by subtype to maintain confidentiality, per NCDB guidelines. Citation Format: Sasha R Douglas, Ingrid Lizarraga, Judy C Boughey, Anna Weiss, Kelly Hunt, Diana Dickson-Witmer, Preeti D Subhedar, Ko Un Park, Beiqun Zhao, Sarah Blair. Trends in surgical resection for stage IV breast cancer: Less surgery more systemic treatment [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD7-06.

Abstract Background: Racial disparities in breast cancer outcomes persist in the US, in which black women are more likely to die from breast cancer than white women. Despite levels of mammographic screening comparable to the US, Atlanta has a disproportionate burden of late-stage breast tumors and higher mortality rates, especially among black women. To better understand this disparity, we sought to identify tumor, treatment, and patient characteristics that may contribute to the observed differences in breast cancer mortality between black and white women in the metropolitan Atlanta area. Methods: In this study, patients were identified from the Georgia Cancer Registry. We included 4943 non-Hispanic white and 3580 non-Hispanic black women with an initial diagnosis of stage I-IV primary breast cancer between January 2010 and December 2014 in Atlanta. Cox proportional hazard regression was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) to compare black vs. white breast cancer mortality by tumor (stage, grade, ER status, and molecular subtype), treatment (surgery type, receipt of chemotherapy, radiation, hormone therapy, and trastuzumab), and patient (insurance, marital status, SES, and location of service) characteristics. We performed a mediation analysis to evaluate the contribution of subtype, stage, and socioeconomic status (SES) as mediators on the path between race and breast cancer mortality. Results: Compared with white breast cancer patients, black women were younger with tumors that were higher stage, higher grade, and more likely to be larger, node positive and triple negative. In fully adjusted models, black women diagnosed with Luminal A subtype were 58% more likely to die of breast cancer compared to their white counterparts (HR=1.58, 95%CI 1.31-2.00). Similarly, black women with private insurance were 60% more likely to die of breast cancer (HR=1.61, 95%CI 1.25-1.98), and black women in the highest SES group were more than twice as likely to die from breast cancer (HR=2.26, 95%CI 1.26-4.06) than white women with comparable SES. The smallest disparities in breast cancer mortality by race were observed among women without insurance, in the lowest SES index, or those diagnosed with triple-negative breast cancer. The mediation analysis showed 84.8% of the effect between race and breast cancer mortality was through stage, subtype, and SES. Conclusion: Our results indicate variation in racial disparities in breast cancer mortality by tumor and patient characteristics. Consistent with previous reports, our mediation results suggest that later stage and triple-negative subtype among black women are major contributors of the observed disparity. However, our results also shed new light on the disparity, suggesting that the largest disparities are observed among women with ER+ tumors amenable to adjuvant therapies and are most pronounced among women of high SES. More research is needed to understand the drivers of disparities in these treatable tumors. Citation Format: Lindsay J. Collin, Renjian Jiang, Kevin C. Ward, Keerthi Gogineni, Preeti D. Subhedar, Mark Sherman, Mia M. Gaudet, Carmen Radecki Breitkopf, Olivia D'Angelo, Sheryl Gabram-Mendola, Jolie Siegel, Rana Aneja, Anne Gaglioti, Lauren E. McCullough. Identification of factors contributing to breast cancer mortality disparities in the metropolitan Atlanta area [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C053.

AbstractBackgroundRacial disparities in breast cancer (BC) outcomes persist where non-Hispanic black (NHB) women are more likely to die from BC than non-Hispanic white (NHW) women, and the extent of this disparity varies geographically. We evaluated tumor, treatment, and patient characteristics that contribute to racial differences in BC mortality in Atlanta, Georgia, where the disparity was previously characterized as especially large.MethodsWe identified 4943 NHW and 3580 NHB women in the Georgia Cancer Registry with stage I–IV BC diagnoses in Atlanta (2010–2014). We used Cox proportional hazard regression to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) comparing NHB vs NHW BC mortality by tumor, treatment, and patient characteristics on the additive and multiplicative scales. We additionally estimated the mediating effects of these characteristics on the association between race and BC mortality.ResultsAt diagnosis, NHB women were younger—with higher stage, node-positive, and triple-negative tumors relative to NHW women. In age-adjusted models, NHB women with luminal A disease had a 2.43 times higher rate of BC mortality compared to their NHW counterparts (95% CI = 1.99 to 2.97). High socioeconomic status (SES) NHB women had more than twice the mortality rates than their white counterparts (HR = 2.67, 95% CI = 1.65 to 4.33). Racial disparities among women without insurance, in the lowest SES index, or diagnosed with triple-negative BC were less pronounced.ConclusionsIn Atlanta, the largest racial disparities are observed in luminal tumors and most pronounced among women of high SES. More research is needed to understand drivers of disparities within these treatable features.