Racial/Ethnic Differences and Trends in Pathologic Complete Response Following Neoadjuvant Chemotherapy for Breast Cancer

Racial/ethnic differences in 21-gene recurrence score and survival among patients with estrogen receptor-positive breast cancer

BACKGROUND

Despite numerous studies on racial/ethnic disparities among patients with breast cancer, there is a paucity of literature evaluating racial/ethnic differences in 21-gene recurrence score (RS) and survival differences stratified by RS risk categories. We thus performed an observational cohort study to examine racial/ethnic disparities in the context of RS.

METHODS

The National Cancer Database (NCDB) was queried for female patients diagnosed between 2006 and 2018 with estrogen receptor (ER)-positive, pT1-3N0-1aM0 breast cancer who received surgery followed by adjuvant endocrine therapy and had RS data available. Logistic multivariable analysis (MVA) was built to evaluate variables associated with RS ≥ 26. Cox MVA was used to evaluate OS. Subgroup analyses were performed to compare the magnitude of racial/ethnic differences stratified by RS. P values less than 0.017 were considered statistically significant based on Bonferroni correction.

RESULTS

A total of 140,133 women were included for analysis. Of these, 115,651 (82.5%), 8,213 (5.9%), 10,814 (7.7%), and 5,455 (3.9%) were NHW, Hispanic, Black, and API women, respectively. Median (IQR) follow up was 66.2 months (48.0-89.8). Logistic MVA showed that, compared with NHW women, Black women were associated with higher RS (≥ 26 vs < 26: adjusted odds ratio [aOR] 1.19, 95% confidence interval [CI] 1.12-1.26, p < 0.001), while HW (aOR 0.93, 95% CI 0.86-1.00, p = 0.04) and API women (aOR 1.03, 95% CI 0.95-1.13, p = 0.45) were not. Cox MVA showed that, compared with NHW women, Black women had worse OS (adjusted hazards ratio [aHR] 1.10, 95% CI 1.02-1.19, p = 0.012), while HW (aHR 0.85, 95% CI 0.77-0.94, p = 0.001) and API (aHR 0.66, 95% CI 0.56-0.77, p < 0.001) women had better OS. In subgroup analysis, similar findings were noted among those with RS < 26, while only API women were associated with improved OS among others with RS ≥ 26.

CONCLUSION

To our knowledge, this is the largest study using nationwide oncology database to suggest that Black women were associated with higher RS, while HW and API women were not. It also suggested that Black women were associated with worse OS among those with RS < 26, while API women were associated with improved OS regardless of RS when compared to NHW women.

Racial and socioeconomic disparities in triple-negative breast cancer treatment

INTRODUCTION

Triple-negative breast cancer (TNBC) continues to be a significant concern, especially among minority populations, where treatment disparities are notably pronounced. Addressing these disparities, especially among African American women and other minorities, is crucial for ensuring equitable healthcare.

AREAS COVERED

This review delves into the continuum of TNBC treatment, noting that the standard of care, previously restricted to chemotherapy, has now expanded due to emerging clinical trial results. With advances like PARP inhibitors, immunotherapy, and antibody-drug conjugates, a more personalized treatment approach is on the horizon. The review highlights innovative interventions tailored for minorities, such as utilizing technology like text messaging, smartphone apps, and targeted radio programming, coupled with church-based behavioral interventions.

EXPERT OPINION

Addressing TNBC treatment disparities demands a multifaceted approach, blending advanced medical treatments with culturally sensitive community outreach. The potential of technology, especially in the realm of promoting health awareness, is yet to be fully harnessed. As the field progresses, understanding and integrating the socio-economic, biological, and access-related challenges faced by minorities will be pivotal for achieving health equity in TNBC care.

Machine learning prediction of pathological complete response and overall survival of breast cancer patients in an underserved inner-city population

BACKGROUND

Generalizability of predictive models for pathological complete response (pCR) and overall survival (OS) in breast cancer patients requires diverse datasets. This study employed four machine learning models to predict pCR and OS up to 7.5 years using data from a diverse and underserved inner-city population.

METHODS

Demographics, staging, tumor subtypes, income, insurance status, and data from radiology reports were obtained from 475 breast cancer patients on neoadjuvant chemotherapy in an inner-city health system (01/01/2012 to 12/31/2021). Logistic regression, Neural Network, Random Forest, and Gradient Boosted Regression models were used to predict outcomes (pCR and OS) with fivefold cross validation.

RESULTS

pCR was not associated with age, race, ethnicity, tumor staging, Nottingham grade, income, and insurance status (p > 0.05). ER-/HER2+ showed the highest pCR rate, followed by triple negative, ER+/HER2+, and ER+/HER2- (all p < 0.05), tumor size (p < 0.003) and background parenchymal enhancement (BPE) (p < 0.01). Machine learning models ranked ER+/HER2-, ER-/HER2+, tumor size, and BPE as top predictors of pCR (AUC = 0.74-0.76). OS was associated with race, pCR status, tumor subtype, and insurance status (p < 0.05), but not ethnicity and incomes (p > 0.05). Machine learning models ranked tumor stage, pCR, nodal stage, and triple-negative subtype as top predictors of OS (AUC = 0.83-0.85). When grouping race and ethnicity by tumor subtypes, neither OS nor pCR were different due to race and ethnicity for each tumor subtype (p > 0.05).

CONCLUSION

Tumor subtypes and imaging characteristics were top predictors of pCR in our inner-city population. Insurance status, race, tumor subtypes and pCR were associated with OS. Machine learning models accurately predicted pCR and OS.

Long-Term Outcomes and Predictors of Response in Breast Cancer Patients with Advanced Nodal Involvement

BACKGROUND

Advanced nodal disease is associated with poor prognosis. However, modern neoadjuvant systemic therapy (NST) regimens have resulted in higher pathologic complete response (pCR) rates, which are associated with improved survival. We sought to assess contemporary outcomes in patients with advanced nodal involvement and response to NST.

STUDY DESIGN

We conducted a single-institution, retrospective study of 521 patients with cN2-3 primary nonmetastatic breast cancer treated with NST followed by surgery and radiation from 2012 to 2018. Descriptive statistics, multivariate Cox regression, and Kaplan-Meier analyses were performed.

RESULTS

The mean age was 50.5 years, and median follow-up was 61 (4.7 to 197) months. The majority of patients had hormone receptor-positive (HR+)/HER2-negative tumors (HER2-; n = 242, 47.8%). Most were cT2 (n = 243; 46.6%) or cT3 (n = 139; 26.7%) and 73.3% (n = 382) had cN3 disease. Rate of axillary pCR was 34.2%, and breast and axillary pCR was 19.4% (n = 101). Event-free survival (EFS) at 5 years was 75.1% (95% CI, 0.71 to 0.79). Rate of locoregional recurrence was 6.7%; distant metastatic rate was 29.4%. Axillary pCR with or without breast pCR was significantly associated with longer EFS (p = 0.001). Achieving breast/axillary pCR was an independent predictor of improved EFS (hazard ratio 0.22, p < 0.0001). Having triple-negative disease was associated with worse EFS (hazard ratio 1.74, p = 0.008).

CONCLUSIONS

In a high-risk cohort of patients with cN2-3 disease, trimodality therapy was effective in achieving durable EFS. Approximately one-third of patients achieved axillary pCR, which was associated with improved survival. Further studies are needed to accurately determine axillary response in cN2-3 breast cancer after NST in order to develop de-escalation strategies to reduce morbidity associated with axillary surgery.

Near-Infrared Spectral Tomography for Predicting Residual Cancer Burden during Early-Stage Neoadjuvant Chemotherapy for Breast Cancer

PURPOSE

The aim of this study is to investigate whether near-infrared spectral tomography (NIRST) might serve as a reliable prognostic tool to predict residual cancer burden (RCB) in patients with breast cancer undergoing neoadjuvant chemotherapy (NAC) based upon early treatment response measurements.

EXPERIMENTAL DESIGN

A total of thirty-five patients with breast cancer receiving NAC were included in this study. NIRST imaging was performed at multiple time points, including: before treatment, at end of the first cycle, at the mid-point, and post-NAC treatments. From reconstructed NIRST images, average values of total hemoglobin (HbT) were obtained for both the tumor region and contralateral breast at each time point. RCB scores/classes were assessed by a pathologist using histologic slides of the surgical specimen obtained after completing NAC. Logistic regression of the normalized early percentage change of HbT in the tumor region (ΔHbT%) was used to predict RCB and determine its significance as an indicator for differentiating cases within each RCB class.

RESULTS

The ΔHbT% at the end of the first cycle, as compared with pretreatment levels, showed excellent prognostic capability in differentiating RCB-0 from RCB-I/II/III or RCB-II from RCB-0/I/III (P < 0.001). Corresponding area under the curve (AUC) values for these comparisons were 0.97 and 0.94, and accuracy values were 0.90 and 0.83, respectively.

CONCLUSIONS

NIRST holds promise as a potential clinical tool that can be seamlessly integrated into existing clinical workflow within the infusion suite. By providing early assessment of RCB, NIRST has potential to improve breast cancer patient management strategies.

Racial and Ethnic Disparity in Preoperative Chemosensitivity and Survival in Patients With Early-Stage Breast Cancer

Importance

It remains unclear what survival benefit is associated with preoperative chemosensitivity after receiving neoadjuvant chemotherapy (NACT) among patients with resectable breast cancer from diverse racial and ethnic backgrounds.

Objective

To investigate racial and ethnic disparities in chemosensitivity and association with survival in patients with early-stage breast cancer.

Design, Setting, and Participants

This retrospective cohort study queried data from the National Cancer Database (NCDB) between calendar years 2010 and 2018. Participants included patients with breast cancer with clinical stage I to III disease treated with NACT. Preoperative chemosensitivity was defined as very sensitive (ypT0N0), sensitive (pathologic TNM stage less than clinical stage, excluding ypT0N0), and refractory (pathologic stage greater than or equal to clinical stage). Data were analyzed in November 2022.

Exposure

Receipt of NACT and clinicopathologic and treatment factors contributing to racial and ethnic disparities in survival.

Main Outcomes and Measures

Overall survival of patients from diverse racial and ethnic backgrounds who received NACT.

Results

This study included 103 605 patients (median age, 53 [IQR, 44-62] years, 99.5% [n = 103 060] women, and 68.7% [n = 71 203] White race). Among them, breast cancer was refractory in 43.2% (n = 44 796), sensitive in 34.4% (n = 35 638), and very sensitive in 22.4% (n = 23 171) of patients. In the hormone receptor-positive ERBB2 negative (formerly HER2 negative) group, patients had more refractory disease regardless of race or ethnicity (all races and ethnicities refractory: 54%-59%; P < .001). Among ERBB2 positive disease, Black patients had a lower percentage of very sensitive disease (32% vs 37%-40%; P < .001) and among triple-negative breast cancer, more refractory disease was seen among Black patients compared with other races and ethnicities (38% vs 30%-35%; P < .001). In refractory (hazard ratio [HR], 1.53; 95% CI, 1.47-1.60; P < .001) and sensitive (HR, 1.25; 95% CI, 1.17-1.33; P < .001) disease, Black patients had a higher mortality risk compared with White patients in the overall cohort. Asian patients had a lower mortality risk compared with White patients in refractory (HR, 0.71; 95% CI, 0.63-0.80; P < .001), sensitive (HR, 0.58; 95% CI, 0.49-0.69; P < .001), and very sensitive (HR, 0.60; 95% CI, 0.43-0.82; P < .001) disease groups in the overall cohort.

Conclusions and Relevance

In this cohort study, Black patients had a higher mortality risk compared with White patients among those with residual disease after NACT. This highlights the need for personalized treatment strategies for Black patients to help them attain pathologic complete response.

Outcomes in breast cancer-does ethnicity matter?

Ethnic or racial differences in breast cancer (BC) survival outcomes have been reported, but current data are largely restricted to comparisons between African Americans and non-Hispanic whites. Most analyses have traditionally been based on self-reported race which may not always be accurate, or are oversimplified in their classification. With increasing globalization, quantification of the genetic ancestry from genomic data may offer a solution to infer the complex makeup from admixture of races. Focusing on the larger and the latest studies, we will discuss recent findings on the differing host and tumor biology that may be driving these disparities, in addition to the extrinsic environmental or lifestyle factors. Socioeconomic disparities with lower cancer literacy may lead to late presentation, poorer adherence to treatment, and other lifestyle factors such as unhealthy diet, obesity, and inadequate physical activity. These hardships may also result in greater allostatic load, which is in turn associated with aggressive BC features in disadvantaged populations. Epigenetic reprogramming may mediate the effects of the environment or lifestyle factors on gene expression, with ensuing differences in BC characteristics and outcome. There is increasing evidence that germline genetics can influence somatic gene alterations or expression, as well as modulate the tumor or immune microenvironment. Although the precise mechanisms remain elusive, this may account for the varying distribution of different BC subtypes across ethnicities. These gaps in our knowledge highlight the need to interrogate the multiomics landscape of BC in diverse populations, ideally in large-scale collaborative settings with standardized methodology for the comparisons to be statistically robust. Together with improving BC awareness and access to good quality health care, a holistic approach with insights of the biological underpinnings is much needed to eradicate ethnic disparities in BC outcomes.

Disparities in Survival and Comorbidity Burden Between Asian and Native Hawaiian and Other Pacific Islander Patients With Cancer

IMPORTANCE

Improper aggregation of Native Hawaiian and other Pacific Islander individuals with Asian individuals can mask Native Hawaiian and other Pacific Islander patient outcomes. A comprehensive assessment of cancer disparities comparing Asian with Native Hawaiian and other Pacific Islander populations is lacking.

OBJECTIVE

To compare comorbidity burden and survival among East Asian, Native Hawaiian and other Pacific Islander, South Asian, and Southeast Asian individuals with non-Hispanic White individuals with cancer.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used a national hospital-based oncology database enriched with Native Hawaiian and other Pacific Islander and Asian populations. Asian, Native Hawaiian and other Pacific Islander, and White individuals diagnosed with the most common cancers who received treatment from January 1, 2004, to December 31, 2017, were included. Patients younger than 18 years, without pathologic confirmation of cancer, or with metastatic disease were excluded. Data were analyzed from January to May 2022.

MAIN OUTCOMES AND MEASURES

The primary end points were comorbidity burden by Charlson-Deyo Comorbidity Index and overall survival (OS).

RESULTS

In total, 5 955 550 patients were assessed, including 60 047 East Asian, 11 512 Native Hawaiian and other Pacific Islander, 25 966 South Asian, 42 815 Southeast Asian, and 5 815 210 White patients. The median (IQR) age was 65 (56-74) years, median (IQR) follow-up was 58 (30-96) months, and 3 384 960 (57%) were women. Patients were predominantly from metropolitan areas (4 834 457 patients [84%]) and the Southern United States (1 987 506 patients [34%]), with above median education (3 576 460 patients [65%]), and without comorbidities (4 603 386 patients [77%]). Cancers included breast (1 895 351 patients [32%]), prostate (948 583 patients [16%]), kidney or bladder (689 187 patients [12%]), lung (665 622 patients [11%]), colorectal (659 165 patients [11%]), melanoma (459 904 patients [8%]), endometrial (307 401 patients [5%]), lymphoma (245 003 patients [4%]), and oral cavity (85 334 patients [1%]) malignant neoplasms. Native Hawaiian and other Pacific Islander patients had the highest comorbidity burden (adjusted odds ratio [aOR], 1.70; 95% CI, 1.47-1.94) compared with Asian and White groups. Asian patients had superior OS compared with White patients for most cancers; only Southeast Asian patients with lymphoma had inferior survival (adjusted hazard ratio [aHR], 1.26; 95% CI, 1.16-1.37). In contrast, Native Hawaiian and other Pacific Islander patients demonstrated inferior OS compared with Asian and White patients for oral cavity cancer (aHR, 1.56; 95% CI, 1.14-2.13), lymphoma (aHR, 1.35; 95% CI, 1.11-1.63), endometrial cancer (aHR, 1.30; 95% CI, 1.12-1.50), prostate cancer (aHR, 1.29; 95% CI, 1.14-1.46), and breast cancer (aHR, 1.09; 95% CI, 1.00-1.18). No cancers among Native Hawaiian and other Pacific Islander patients had superior OS compared with White patients.

CONCLUSIONS AND RELEVANCE

In this cohort study, compared with White patients with the most common cancers, Asian patients had superior survival outcomes while Native Hawaiian and other Pacific Islander patients had inferior survival outcomes. Native Hawaiian and other Pacific Islander patients had significantly greater comorbidity burden compared with Asian and White patients, but this alone did not explain the poor survival outcomes. These results support the disaggregation of these groups in cancer studies.

Understanding drivers of the Black:White breast cancer mortality gap: A call for more robust definitions

Kim et al completed a pooled analysis of 8 National Surgical Adjuvant Breast and Bowel Project trials and highlight that, when compared with White patients, Black patients with estrogen receptor–positive (ER+) breast cancer have worse distant recurrence‐free survival, especially in the setting of neoadjuvant chemotherapy when pathologic complete response is not achieved. This editorial highlights that, to comprehend the drivers of this disparity, we must have more robust definitions of ER+ breast cancer and race.