Racial and Socioeconomic Disparities in Breast Cancer Outcomes within the AJCC Pathologic Prognostic Staging System

Racial Disparities in Locoregional Recurrence in Postmenopausal Patients with Stage I-III, Hormone Receptor-Positive Breast Cancer Enrolled in the NSABP B-42 Clinical Trial

BACKGROUND

There are limited data examining racial disparities in locoregional recurrence (LRR) among women with access to high-quality care. We aimed to examine differences in late LRR by race in patients with stage I-IIIA, hormone receptor-positive (HR+) breast cancer enrolled in the National Surgical Adjuvant Breast and Bowel (NSABP) B-42 trial.

METHODS

From 2006 to 2010, 3966 postmenopausal women with stage I-IIIA HR+ breast cancer who were disease-free after 5 years of endocrine therapy were randomized to an additional 5 years of endocrine therapy or placebo. Patients were excluded if multi-racial or if race was unknown. Kaplan-Meier curves were used to estimate 6-year LRR from the time of trial registration and according to race. Cox proportional hazards models were used for adjusted survival analyses.

RESULTS

Overall, 3929 NSABP B-42 patients were included: 3688 (93.9%) White, 151 (3.8%) Black, and 90 (2.3%) Asian patients. Median follow-up was 75.2 months. Overall estimated 6-year LRR from trial registration was 1.8% and differed by race: LRR rates were 1.7% in White women, 4.9% in Black women, and 0% in Asian women (p = 0.046). Adjusted Cox proportional hazards analysis found Black race to be independently associated with LRR (hazard ratio [HzR] 2.36, 95% confidence interval [CI] 1.01-5.49; p = 0.047). Node-positivity was also associated with increased LRR (HzR 1.75, 95% CI 1.07-2.86; p = 0.025). Adjusted Cox analysis found LRR (HzR 2.32, 95% CI 1.33-4.06; p = 0.003) to be associated with increased overall mortality; however, race was not independently associated with mortality.

CONCLUSION

Among postmenopausal patients with stage I-IIIA HR+ breast cancer in the NSABP B-42 trial, racial differences in late LRR were present, with the highest LRR in Black women.

Racial and Ethnic Disparities in Locoregional Recurrence Among Patients With Hormone Receptor-Positive, Node-Negative Breast Cancer: A Post Hoc Analysis of the TAILORx Randomized Clinical Trial

Importance

Whether racial and ethnic disparities in locoregional recurrence (LRR) exist among patients with similar access to care treated in randomized clinical trials is unknown.

Objective

To examine racial and ethnic differences in LRR among patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (ERBB2 [formerly HER2 or HER2/neu])-negative, node-negative breast cancer enrolled in the Trial Assigning Individualized Options for Treatment (TAILORx).

Design, Setting, and Participants

This unplanned retrospective post hoc analysis examined a prospective multicenter clinical trial population of women with breast cancer enrolled between 2006 and 2010, with 9 years of follow-up. The TAILORx investigators randomized patients to treatment based on their Oncotype DX recurrence score, including endocrine therapy alone (recurrence score <11), endocrine therapy alone vs chemotherapy followed by endocrine therapy (recurrence score 11-25), or chemotherapy followed by endocrine therapy (recurrence score >25). Patients with unknown race and ethnicity or lack of follow-up were excluded from this analysis. Data analysis was performed between December 2021 and March 2022.

Main Outcome and Measures

Locoregional recurrence was defined as ipsilateral in breast, skin, chest wall, or regional nodal recurrence without concurrent distant recurrence, and was stratified by racial and ethnic group. Unadjusted Kaplan-Meier and adjusted Cox proportional hazards regression models were used for survival analyses.

Results

Of the 10 273 women enrolled in TAILORx, this analysis included 9369 with T1-2N0 HR-positive, ERBB2-negative breast cancer. Of these patients, 428 (4.6%) were Asian, 886 (9.4%) were Hispanic, 676 (7.2%) were non-Hispanic Black (hereinafter Black), and 7406 (78.8%) were non-Hispanic White (hereinafter White). Assigned treatment receipt was high, with a 9.3% (n = 870) crossover of treatment groups and a median endocrine therapy duration of longer than 60 months, ranging from 61.1 to 65.9 months, across racial and ethnic groups. A total of 6818 patients (72.6%) received radiation (6474 [96.1%] after breast-conserving surgery and 344 [13.0%] after mastectomy). At a median follow-up of 94.8 months (range, 1-138 months), 8-year LRR rates were 3.6% (95% CI, 1.6%-5.6%) in Asian patients, 3.9% (95% CI, 2.2%-5.4%) in Black patients, 3.1% in Hispanic patients (95% CI, 1.7%-4.5%), and 1.8% (95% CI, 1.5%-2.3%) in White patients (P < .001). In survival analyses adjusted for patient, tumor, and treatment factors, Asian race (hazard ratio, 1.91 [95% CI, 1.12-3.29]) and Black race (1.78 [1.15-2.77]) were independently associated with LRR. In adjusted survival analyses for breast cancer mortality, LRR was independently associated with increased breast cancer mortality (hazard ratio, 5.71 [95% CI, 3.50-9.31]).

Conclusions and Relevance

In this post hoc analysis, racial and ethnic differences in LRR were observed among patients with T1-2N0 HR-positive, ERBB2-negative breast cancer despite high rates of treatment receipt in this clinical trial population, with the highest LRR rates in Asian and Black patients. Further study is needed to understand whether failure to rescue after LRR may contribute to racial disparities in breast cancer mortality.

Trial Registration

ClinicalTrials.gov Identifier: NCT00310180.

Stage-Specific Survival in Breast Cancer in Chinese and White Women: Comparative Data Analysis

BACKGROUND

Stage-specific survival, according to the eighth edition of the American Joint Committee on Cancer (AJCC) pathological prognostic staging (PPS) on breast cancer (BC), between Chinese and White American women remains unclear.

OBJECTIVE

This study aimed to assess stage-specific survival in BC between Chinese and White American women according to the eighth AJCC PPS.

METHODS

We included Chinese and White American women with BC diagnosed between 2010 and 2018 from the Surveillance, Epidemiology, and End Results database. A chi-square test, the Kaplan-Meier method, a receiver operating characteristic (ROC) curve, and multivariate Cox proportional hazards models were used for data analysis.

RESULTS

We included 376,818 individuals in this study: 369,522 White American and 7296 Chinese. Of them, 149,452 (39.7%) migrated from the seventh AJCC anatomic staging (AS) to the eighth AJCC PPS, 22,516 (6.0%) were upstaged, and 126,936 (33.7%) were downstaged. With a median follow-up duration of 44 months, the 5-year overall survival and cancer-specific survival (CSS) for the entire group were 87.4% and 95.9%, respectively. The seventh AJCC AS (P<.001) and the eighth AJCC PPS (P<.001) could significantly predict the survival outcomes of BC, and multivariate analysis revealed that both staging systems were significant prognostic indicators of CSS. The ROC curve revealed that the PPS had a better discriminating ability than the AS (area under the curve [AUC] 0.769 vs 0.753, P<.001). Similar trends were observed after stratification by the 2 ethnic groups. The eighth AJCC PPS had better discriminating ability than the seventh AJCC AS among both White American (AUC 0.769 vs 0.753, P<.001) and Chinese patients (AUC 0.790 vs 0.776, P<.001). In the seventh AJCC AS, Chinese women had better CSS in stage IA (P=.02), stage IIA (P=.005), and stage IIIB (P=.04) disease than White American women, but no significant CSS was observed in stage IB, IIB, IIIA, and IIIC disease between the 2 ethnic groups. Regarding the eighth AJCC PPS, Chinese women had better CSS in stage IA (P=.002) and IIIA (P=.046) disease than White American women, and CSS was similar in Chinese and White American women in other substages.

CONCLUSIONS

The eighth AJCC PPS has a similar discriminative ability between White American and Chinese individuals with BC compared with the seventh AJCC AS. Therefore, the eighth AJCC PPS is also applicable to Chinese individuals with BC.

Determining prognostic factors and optimal surgical intervention for early-onset triple-negative breast cancer

Background

Few studies have focused specifically on prognostic factors and optimal surgical intervention for early-onset triple-negative breast cancer (eTNBC), which is characterized by high malignancy and poor prognosis.

Methods

We performed a cohort study with a median follow-up of 31 months using Surveillance, Epidemiology, and End Results (SEER) data of patients diagnosed with stages I–III eTNBC between 2010 and 2016. In addition, we collected cases between 2006 and 2016 from our center as an external validation set. Clinical features, pathologic characteristics and oncologic outcomes were analyzed. Prognostic factors for overall survival (OS) and breast cancer-specific survival (BCSS) were determined by Cox proportional hazards analyses and were incorporated into the prognostic nomogram. Subgroup analysis based on propensity score matching method was conducted to explore the subset of patients that would benefit from breast-conserving therapy (BCT).

Results

Based on SEER dataset, patients with eTNBC were more likely to undergo mastectomy than BCT. On multivariable analysis, patients with better survival outcomes were those not married, uninsured, had higher T and N stage, and had histological type of mixed invasive ductal and lobular carcinoma. The prognostic nomogram based on these variables successfully predicted the 3- and 5-year BCSS (C-index in training cohort, 0.774; in validation cohort from SEER, 0.768; in validation cohort from our center, 0.723). Subgroup analysis illustrated that patients with T1N0M0 or T2-4N+M0 tumors who underwent BCT achieved longer overall survival than those who underwent mastectomy (for T1N0M0, P = 0.022; for T2-4N+M0, P = 0.003); however, the type of surgery did not influence OS among patients with T1N+M0 or T2-4N0M0 tumors (for T1N+M0, P = 0.305; for T2-4N0M0, P = 0.317).

Conclusions

The prognosis of patients with eTNBC is mainly affected by marital status, insurance status, T stage, N stage and histological type. The prognostic nomogram based on these factors is quite reliable. Subgroup analysis suggested that BCT may be a superior option for patients with eTNBC, especially those with T1N0M0 and T2-4N+M0 tumors.

Racial Disparity in Quadruple Negative Breast Cancer: Aggressive Biology and Potential Therapeutic Targeting and Prevention

Simple Summary

Quadruple negative breast cancer (QNBC), a subgroup of triple negative BC, has emerged as a highly aggressive BC subtype that disproportionately afflicts and impacts Black/African-American (AA) women. In this article, we review molecular distinctions in Black/AA and White/European-American (EA) QNBC biology as well as address potential non-genetic risk factors that could be underlying this racially disparate burden. We aim to provide deeper insight and provide a framework for novel discovery of actionable therapeutic targets and identify lifestyle changes to improve outcomes for Black/AA QNBC patients.

Abstract

Black/African-American (AA) women, relative to their White/European-American (EA) counterparts, experience disproportionately high breast cancer mortality. Central to this survival disparity, Black/AA women have an unequal burden of aggressive breast cancer subtypes, such as triple-negative breast cancer (ER/PR-, HER2-wild type; TNBC). While TNBC has been well characterized, recent studies have identified a highly aggressive androgen receptor (AR)-negative subtype of TNBC, quadruple-negative breast cancer (ER/PR-, HER2-wildtype, AR-; QNBC). Similar to TNBC, QNBC disproportionately impacts Black/AA women and likely plays an important role in the breast cancer survival disparities experienced by Black/AA women. Here, we discuss the racial disparities of QNBC and molecular signaling pathways that may contribute to the aggressive biology of QNBC in Black/AA women. Our immediate goal is to spotlight potential prevention and therapeutic targets for Black/AA QNBC; ultimately our goal is to provide greater insight into reducing the breast cancer survival burden experienced by Black/AA women.

Impact of Social Vulnerability on Comorbid Cancer and Cardiovascular Disease Mortality in the United States

Background

Racial and social disparities exist in outcomes related to cancer and cardiovascular disease (CVD).

Objectives

The aim of this cross-sectional study was to study the impact of social vulnerability on mortality attributed to comorbid cancer and CVD.

Methods

The Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research database (2015-2019) was used to obtain county-level mortality data attributed to cancer, CVD, and comorbid cancer and CVD. County-level social vulnerability index (SVI) data (2014-2018) were obtained from the CDC's Agency for Toxic Substances and Disease Registry. SVI percentiles were generated for each county and aggregated to form SVI quartiles. Age-adjusted mortality rates (AAMRs) were estimated and compared across SVI quartiles to assess the impact of social vulnerability on mortality related to cancer, CVD, and comorbid cancer and CVD.

Results

The AAMR for comorbid cancer and CVD was 47.75 (95% CI: 47.66-47.85) per 100,000 person-years, with higher mortality in counties with greater social vulnerability. AAMRs for cancer and CVD were also significantly greater in counties with the highest SVIs. However, the proportional increase in mortality between the highest and lowest SVI counties was greater for comorbid cancer and CVD than for either cancer or CVD alone. Adults <45 years of age, women, Asian and Pacific Islanders, and Hispanics had the highest relative increase in comorbid cancer and CVD mortality between the fourth and first SVI quartiles, without significant urban-rural differences.

Conclusions

Comorbid cancer and CVD mortality increased in counties with higher social vulnerability. Improved education, resource allocation, and targeted public health interventions are needed to address inequities in cardio-oncology.

Racial and Ethnic Inequality in Survival Outcomes of Women With Triple Negative Breast Cancer

Purpose

Triple-negative breast cancer (TNBC) is the most lethal group of breast cancers. Socioeconomic factors may contribute to differences in survival rates. This study aims to identify racial/ethnic disparities in five-year survival rates among women affected by TNBC in the United States.

Methods

This retrospective study analyzed data from the 2010-2016 Surveillance, Epidemiology, and End Results Program database. Patients with a primary malignancy of triple-negative breast cancer were included in this study. Cancer-specific survival was measured at five years post-diagnosis. Cox regression models were used to calculate hazard ratios (HR) and corresponding 95% confidence intervals (CI).

Results

From 2010-2016, there were 26,963 women with a primary diagnosis of TNBC. After adjustment for age, insurance, marital status, stage, and surgery type, Hispanic women had the highest hazard of death when compared to White women (adjusted (adj) HR, 1.14, p<0.001). Further, non-Hispanic Black women also had a lower survival probability when compared to White women (adj HR, 1.06, p=0.002).

Conclusion

This study reveals that Hispanic women had the highest hazard of death when compared to White women. As TNBC is the most fatal breast cancer, future studies should investigate socioeconomic factors that may worsen prognosis of this disease.

Race and Site of Care Impact Treatment Delays in Older Women with Non-Metastatic Breast Cancer

BACKGROUND

Women ≥ 65 years of age are less likely to receive guideline-concordant breast cancer care. Given existing racial/ethnic disparities, older minority breast cancer patients may be especially prone to inequalities in care. How site of care impacts older breast cancer patients is not well defined. We sought to evaluate the association between race/ethnicity and breast cancer treatment delays in older women treated at minority-serving hospitals (MSHs) versus non-MSHs.

METHODS

Women ≥ 65 years of age treated for non-metastatic breast cancer were identified in the National Cancer Database (2010-2017). Treatment delay was defined as > 90 days from diagnosis to initial treatment. MSHs were defined as the top decile of hospitals serving predominantly Black or Hispanic patients. Multivariable logistic regression models adjusted for patient, tumor, and hospital characteristics were used to determine the odds of treatment delay for women at MSHs versus non-MSHs across racial/ethnic groups.

RESULTS

Overall, 557,816 women were identified among 41 MSHs and 1146 non-MSHs. Average time to treatment was 33.71 days (standard deviation 26.92 days). Older women at MSHs were more likely to experience treatment delays than those at non-MSHs (odds ratio 1.28, 95% confidence interval 1.21-1.36). Regardless of where they received care, minorities were more likely to experience treatment delays than non-Hispanic White women.

CONCLUSIONS

Although 97% of older women treated at Commission on Cancer-accredited hospitals received timely breast cancer care, minorities and those treated at MSHs were more likely to experience treatment delays. Interventions addressing barriers to timely breast cancer care at MSHs may be an effective approach to reducing racial/ethnic disparities.