Prospective investigation of amino acid transport and PSMA-targeted positron emission tomography for metastatic lobular breast carcinoma.

PURPOSE: To explore the feasibility of imaging amino-acid transport and PSMA molecular pathways in the detection of metastatic breast invasive lobular carcinoma (ILC) and if there is superior detection compared to standard-of-care imaging [computed tomography (CT)/bone scan, or 18F-FDG positron-emission-tomography (PET)-CT]. METHODS: 20 women with de-novo or suspected metastatic ILC underwent two PET-CT scans with 18F-fluciclovine and 68Ga-PSMA-11 on separate days. Uptake per patient and in 3 regions per patient - ipsilateral axillary lymph node (LN), extra-axillary LN (ipsilateral supraclavicular or internal mammary), or distant sites of disease - was compared to standard-of-care imaging (CT/bone scan in 13 patients and 18F-FDG PET-CT in 7 patients). Results were correlated to a composite standard of truth. Confirmed detection rate (cDR) was compared using McNemar's test. Mean SUVmax of 18F-fluciclovine and 68Ga-PSMA-11 in the most avid lesion for each true positive metastatic region and intact primary lesion were compared by t-test. RESULTS: The cDR for standard-of-care imaging was 5/20 patients in 5/60 regions. 68Ga-PSMA-11 PET-CT detected metastasis in 7/20 patients in 7/60 regions. 18F-fluciclovine PET-CT detected metastasis in 9/20 patients in 12/60 regions. The cDR for 18F-fluciclovine PET-CT was significantly higher versus standard-of-care imaging on the patient and combined region levels, while there were no significant differences between 68Ga-PSMA-11 and standard-of care imaging. 18F-fluciclovine cDR was also significantly higher than 68Ga-PSMA-11 on the combined region level. Mean SUVmax for true positive metastatic and primary lesions with 18F-fluciclovine (n = 18) was significantly greater than for 68Ga-PSMA-11 (n = 11) [5.5 ± 1.8 versus 3.5 ± 2.7 respectively, p = 0.021]. CONCLUSION: In this exploratory trial, 18F-fluciclovine PET-CT has a significantly higher cDR for ILC metastases compared to standard-of-care imaging and to 68Ga-PSMA-11. Mean SUVmax for true positive malignancy was significantly higher with 18F-fluciclovine than for 68Ga-PSMA-11. Exploratory data from this trial suggests that molecular imaging of amino acid metabolism in patients with ILC deserves further study. CLINICAL TRIAL REGISTRATION: Early phase (I-II) clinical trial (NCT04750473) funded by the National Institutes of Health (R21CA256280).

Analysis of travel burden and travel support among patients treated at a comprehensive cancer center in the Southeastern United States.

INTRODUCTION: Travel burden leads to worse cancer outcomes. Understanding travel burden and the level and types of travel support provided at large cancer centers is critical for developing systematic programs to alleviate travel burden. This study analyzed patients who received travel assistance, including their travel burden, types and amount of travel support received, and factors that influenced these outcomes. METHODS: We analyzed 1063 patients who received travel support from 1/1/2021 to 5/1/2023 at Winship Cancer Institute, in which ~18,000 patients received cancer care annually. Travel burden was measured using distance and time to Winship sites from patients' residential address. Travel support was evaluated using the monetary value of total travel support and type of support received. Patients' sociodemographic and clinical factors were extracted from electronic medical records. Area-level socioeconomic disadvantage was coded by the Area Deprivation Index using patient ZIP codes. RESULTS: On average, patients traveled 57.2 miles and 67.3 min for care and received $74.1 in total for travel support. Most patients (88.3%) received travel-related funds (e.g., gas cards), 5% received direct rides (e.g., Uber), 3.8% received vouchers for taxi or public transportation, and 3% received combined travel support. Male and White had longer travel distance and higher travel time than female and other races, respectively. Patients residing in more disadvantaged neighborhoods had an increased travel distance and travel time. Other races and Hispanics received more travel support ($) than Black and White patients or non-Hispanics. Patients with higher travel distance and travel time were more like to receive travel-related financial support. CONCLUSION: Among patients who received travel support, those from socioeconomically disadvantaged neighborhoods had greater travel burden. Patients with greater travel burden were more likely to receive travel funds versus other types of support. Further understanding of the impact of travel burden and travel support on cancer outcomes is needed.

Leveraging Mobile Health to Improve Capecitabine Adherence Among Women With Breast Cancer: A Pilot Randomized Controlled Trial.

PURPOSE: Oral capecitabine improves convenience compared to intravenous therapies but presents monitoring challenges. We conducted a randomized pilot trial to evaluate a mobile health intervention to remotely monitor capecitabine adherence and patient-reported outcomes (PROs) among women with breast cancer. METHODS: Patients with breast cancer prescribed capecitabine, an oral chemotherapy with a complex, cyclical regimen, were randomly assigned to enhanced usual care (EUC) or PRO arm. Participants were asked to use a smart pill bottle to measure adherence (timing and dose) and complete baseline and 90-day follow-up surveys. PRO participants received text messages for missed or incorrect doses and weekly text-based symptom assessments, and their oncologists received alerts for severe symptoms or missed doses. We compared nonadherence (<80%) and changes from enrollment to follow-up on reported physical and mental health quality-of-life scores and number of severe symptoms by study arm. RESULTS: Overall, 32 women were randomly assigned (17 EUC and 15 PRO): 28 (87.5%) received the intervention and 24 (78.1%) completed the follow-up survey. Among participants who received the intervention, PRO participants responded to 83.3% of symptom questions; 7.7% of PRO participants were nonadherent compared with 40.0% of EUC participants (P = .049). Among those who completed the follow-up survey, 12.5% of PRO participants had reductions in their mental health composite scores compared with 69.2% of EUC participants (P = .011); 10% of PRO participants had more severe symptoms at follow-up compared with 57.1% of EUC participants (P = .019). CONCLUSION: A mobile health intervention using text message reminders and symptom assessments improved medication adherence and mental health quality-of-life scores and lowered symptom burden of patients with breast cancer prescribed capecitabine. Future work should evaluate the longer-term impacts of this intervention.

Prolonging the life of people with metastatic breast cancer in routine clinical practice by adding palbociclib to an aromatase inhibitor from a real-world database analysis: a plain language summary.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of an article about a study called "P-REALITY X" that was published in the medical journal npj Breast Cancer in October 2022. "P-REALITY X" stands for Palbociclib REAl-world first-LIne comparaTive effectiveness studY eXtended. This study used information from a database to look at whether adding a second treatment (palbociclib) to an aromatase inhibitor (AI) helped people with a certain type of breast cancer to live longer. The type of breast cancer is metastatic hormone receptor-positive/human epidermal growth factor-negative breast cancer, also called HR-positive (or HR+)/HER2-negative (or HER2-) breast cancer. The study used information from the Flatiron Database. This database contains unidentified health care information collected from people seen by doctors in the USA. Only data from people who did not participate in a clinical trial were used. When people are treated outside of a clinical trial, this is called the real-world setting, or routine clinical practice. In clinical trials, people lived longer without their disease worsening if they were treated with palbociclib plus an AI versus being treated with an AI only. Based on the results of clinical trials, treatment with palbociclib plus an AI is already approved and recommended for people with HR+/HER2- breast cancer. This study looked at whether people lived longer if they were treated with palbociclib plus an AI versus being treated with an AI only in routine clinical practice as well. WHAT WERE THE RESULTS?: This study showed that, in routine clinical practice, people treated with the medicine palbociclib plus an AI lived longer than people treated with only an AI. WHAT DO THE RESULTS MEAN?: These results support the continued use of palbociclib plus an AI as the standard first medicine to be given to people with metastatic HR+/HER2- breast cancer. Clinical Trial Registration: NCT05361655 (ClinicalTrials.gov).

A Discordant Pattern of Uptake on 68 Ga-PSMA PET/CT Versus 18 F-Fluciclovine PET/CT in Radiation-Induced Hepatitis : Implications for Early Postradiotherapy Imaging-Based Response Assessment.

ABSTRACT: A 62-year-old woman with right-sided invasive lobular breast carcinoma completed external beam radiotherapy 6 weeks before undergoing a 68 Ga-PSMA PET/CT and 18 F-fluciclovine PET/CT scan as part of an ongoing clinical trial (NCT04750473) assessing the performance of these molecular imaging modalities in invasive lobular breast carcinoma. The 68 Ga-PSMA PET/CT demonstrated a band-like area of increased radiotracer uptake in the dome of the right lobe of the liver anteriorly, whereas 18 F-fluciclovine PET/CT done a day later revealed photopenia in the corresponding area of the liver. The external beam radiotherapy plan confirmed that the radiotherapy field overlaid the region of the hepatic discordant radiotracer uptake on the PET/CT scans.

A Tale of 3 Tracers: Contrasting Uptake Patterns of 18F-Fluciclovine, 68Ga-PSMA, and 18F-FDG in the Uterus and Adnexa.

ABSTRACT: A 41-year-old woman with invasive lobular carcinoma of the breast underwent sequential 68Ga-PSMA-11 PET/CT and 18F-fluciclovine PET/CT as part of an ongoing clinical trial (NCT04750473). 68Ga-PSMA PET/CT showed increased radiotracer uptake in the uterine endometrium and left adnexa. 18F-fluciclovine PET/CT showed increased radiotracer uptake in a leiomyomatous uterus. A clinical 18F-FDG PET/CT demonstrated radiotracer uptake in the endometrium and a circumferential area of uptake in the left adnexa, a pattern more similar to the 68Ga-PSMA uptake pattern. This case highlights the discordance in the uptake pattern of 2 radiotracers approved for prostate cancer imaging but increasingly used in non-prostate malignancies imaging.

Ultrasound Histogram Assessment of Acute Breast Toxicity After Breast Cancer Radiation Therapy: A Prospective Longitudinal Study.

Accurate assessment of radiation-induced breast toxicity is crucial for the management of breast radiation therapy (RT). Standard assessment of breast toxicity based on clinicians' visual inspection and palpation has considerable inter- and intra-observer variability. To overcome this challenge, we present an ultrasound histogram method that objectively evaluates radiation-induced breast toxicity longitudinally. In a prospective study, patients enrolled (n = 67) received ultrasound scans at four time points: prior to RT, last day of RT, 3-4 wk post-RT and 9-12-wk post-RT. Ultrasound scans were acquired at five locations (tumor bed and 3, 6, 9 and 12 o'clock) on both breasts. Two hundred sixty-four ultrasound scans and 2640 B-mode images were analyzed. The histogram differences between irradiated and contralateral breasts were calculated to evaluate radiation-induced breast changes. On the basis of the B-mode images, the severity of breast toxicity was graded as absent, mild, moderate or severe. The performance of the histogram method was assessed with the receiver operating characteristic (ROC) curve. The areas under the ROC curve ranged from 0.78 to 0.9 (sensitivity: 0.88-0.96, specificity: 0.53-0.83) at the lower quadrant for differentiating absent/mild from moderate/severe toxicity at various time points. This study provides preliminary evidence that ultrasound histogram differences can serve as an imaging biomarker to longitudinally assess radiation-induced acute toxicity.

Ultrasound-Based Grading System for Radiation-Induced Acute Breast Toxicity.

OBJECTIVES: To introduce an ultrasound-based scoring system for radiation-induced breast toxicity and test its reliability. METHODS: Breast ultrasound (BUS) was performed on 32 patients receiving breast radiotherapy (RT) to assess the radiation-induced acute toxicity. For each patient, both the untreated and irradiated breasts were scanned at five locations: 12:00, 3:00, 6:00, 9:00, and tumor bed to evaluate for heterogenous responses to radiation within the entire breast. In total, 314 images were analyzed. Based on ultrasound findings such as skin thickening, dermis boundary irregularity, and subcutaneous edema, a 4-level, Likert-like grading scheme is proposed: none (G0), mild (G1), moderate (G2), and severe (G3) toxicity. Two ultrasound experts graded the severity of breast toxicity independently and reported the inter- and intra-observer reliability of the grading system. Imaging findings were compared with standard clinical toxicity assessments using Common Terminology Criteria for Adverse Events (CTCAE). RESULTS: The inter-observer Pearson correlation coefficient (PCC) was 0.87 (95% CI: 0.83-0.90, P < .001). For intra-observer repeatability, the PCC of the repeated scores was 0.83 (95% CI: 0.78-0.87, P < .001). Imaging findings were compared with standard clinical toxicity assessments using CTCAE scales. The PCC between BUS scores and CTCAE results was 0.62 (95% CI: 0.35-0.80, P < .001). Among all locations, 6:00 and tumor bed showed significantly greater toxicity compared with 12:00 (P = .04). CONCLUSIONS: BUS can investigate the cutaneous and subcutaneous tissue changes after RT. This BUS-based grading system can complement subjective clinical assessments of radiation-induced breast toxicity with cutaneous and subcutaneous sonographic information.

Racial Disparities in Clinical Outcomes on Investigator-Initiated Breast Cancer Clinical Trials at an Urban Medical Center.

BACKGROUND: Black women are 40% more likely to die of breast cancer compared to White women. Inadequate representation of Black patients in clinical trials may contribute to health care inequity. We aimed to assess breast cancer clinical outcomes in Non-Hispanic Black (Black) versus Non-Hispanic White (White) women with metastatic breast cancer (MBC) enrolled on investigator-initiated clinical trials at Winship Cancer Institute at Emory University, given the significant number of patients from underrepresented minority groups seen at Winship. MATERIALS AND METHODS: Black and White women with MBC on investigator-initiated trials at Emory between 2009 and 2019 were retrospectively evaluated. Univariate analyses and multiple logistic regression models were used to assess clinical response and treatment toxicities. Differences in overall survival between groups was assessed using quantile analysis. RESULTS: Sixty-two women with MBC were included (66% White vs. 34% Black). Black patients had less clinical benefit from the trial therapy as only 57% had partial response or stable disease as best response compared to 78% of White women (P = .09). Quantile analysis showed significant difference in mean survival between Whites and Blacks by the end of follow up (64 vs. 38 months). There were no significant differences in toxicities between groups. CONCLUSION: Participation rates of Black women with MBC on investigator-initiated clinical trials at an urban cancer center were higher compared to key national trials. Black women had worse treatment response and survival. These results reinforce the need for assessment of tumor differences by ancestry and continued improvement in minority representation on clinical trials.

A Novel Biosignature Identifies Patients With DCIS With High Risk of Local Recurrence After Breast Conserving Surgery and Radiation Therapy.

PURPOSE: There is an unmet need to identify women diagnosed with ductal carcinoma in situ (DCIS) with a low risk of in-breast recurrence (IBR) after breast conserving surgery (BCS), which could omit radiation therapy (RT), and also to identify those with elevated IBR risk remaining after BCS plus RT. We evaluated a novel biosignature for a residual risk subtype (RRt) to help identify patients with elevated IBR risk after BCS plus RT. METHODS AND MATERIALS: Women with DCIS treated with BCS with or without RT at centers in the US, Australia, and Sweden (n = 926) were evaluated. Patients were classified into 3 biosignature risk groups using the decision score (DS) and the RRt category: (1) Low Risk (DS ≤2.8 without RRt), (2) Elevated Risk (DS >2.8 without RRt), and (3) Residual Risk (DS >2.8 with RRt). Total and invasive IBR rates were assessed by risk group and treatment. RESULTS: In patients at low risk, there was no significant difference in IBR rates with or without RT (total, P = .8; invasive IBR, P = .7), and there were low overall 10-year rates (total, 5.1%; invasive, 2.7%). In patients with elevated risk, IBR rates were decreased with RT (total: hazard ratio [HR], 0.25; P < .001; invasive: HR, 0.28; P = .005); 10-year rates were 20.6% versus 4.9% (total) and 10.9% versus 3.1% (invasive). In patients with residual risk, although IBR rates decreased with RT after BCS (total: HR, 0.21; P < .001; invasive: HR, 0.29; P = .028), IBR rates remained significantly higher after RT compared with patients with elevated risk (HR, 2.5; 95% CI, 1.2-5.4; P = .018), with 10-year rates of 42.1% versus 14.7% (total) and 18.3% versus 6.5% (invasive). CONCLUSIONS: The novel biosignature identified patients with 3 distinct risk profiles: Low Risk patients with a low recurrence risk with or without adjuvant RT, Elevated Risk patients with excellent outcomes after BCS plus RT, and Residual Risk patients with an elevated recurrence risk remaining after BCS plus RT, warranting potential intensified or alternative treatment approaches.

Real-world study of overall survival with palbociclib plus aromatase inhibitor in HR+/HER2- metastatic breast cancer.

Data on real-world effectiveness of cyclin-dependent kinase 4/6 inhibitor combination therapy versus endocrine therapy alone are limited. The Flatiron Health Analytic Database was used to assess overall survival (OS) in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) metastatic breast cancer (MBC) treated with first-line palbociclib plus an aromatase inhibitor (AI) versus an AI alone in routine US clinical practice. In total, 2888 patients initiated treatment during February 3, 2015-March 31, 2020, with a potential ≥6-month follow-up (cutoff date, September 30, 2020). After stabilized inverse probability treatment weighting, median OS (95% CI) is significantly longer among palbociclib versus AI recipients (49.1 [45.2-57.7] versus 43.2 [37.6-48.0] months; hazard ratio, 0.76 [95% CI, 0.65-0.87]; P < 0.0001). Progression-free survival (95% CI) is 19.3 (17.5-20.7) versus 13.9 (12.5-15.2) months, respectively (hazard ratio, 0.70 [95% CI, 0.62-0.78]; P < 0.0001). These data support first-line palbociclib plus an AI treatment for HR+/HER2- MBC.(Trial number NCT05361655).

DNA methylation signature of chronic low-grade inflammation and its role in cardio-respiratory diseases.

We performed a multi-ethnic Epigenome Wide Association study on 22,774 individuals to describe the DNA methylation signature of chronic low-grade inflammation as measured by C-Reactive protein (CRP). We find 1,511 independent differentially methylated loci associated with CRP. These CpG sites show correlation structures across chromosomes, and are primarily situated in euchromatin, depleted in CpG islands. These genomic loci are predominantly situated in transcription factor binding sites and genomic enhancer regions. Mendelian randomization analysis suggests altered CpG methylation is a consequence of increased blood CRP levels. Mediation analysis reveals obesity and smoking as important underlying driving factors for changed CpG methylation. Finally, we find that an activated CpG signature significantly increases the risk for cardiometabolic diseases and COPD.

Exosomal Metabolic Signatures Are Associated with Differential Response to Neoadjuvant Chemotherapy in Patients with Breast Cancer.

Neoadjuvant chemotherapy (NAC) is commonly used in breast cancer (BC) patients to increase eligibility for breast-conserving surgery. Only 30% of patients with BC show pathologic complete response (pCR) after NAC, and residual disease (RD) is associated with poor long-term prognosis. A critical barrier to improving NAC outcomes in patients with BC is the limited understanding of the mechanisms underlying differential treatment outcomes. In this study, we evaluated the ability of exosomal metabolic profiles to predict NAC response in patients with BC. Exosomes isolated from the plasma of patients after NAC were used for metabolomic analyses to identify exosomal metabolic signatures associated with the NAC response. Among the 16 BC patients who received NAC, eight had a pCR, and eight had RD. Patients with RD had 2.52-fold higher exosome concentration in their plasma than those with pCR and showed significant enrichment of various metabolic pathways, including citrate cycle, urea cycle, porphyrin metabolism, glycolysis, and gluconeogenesis. Additionally, the relative exosomal levels of succinate and lactate were significantly higher in patients with RD than in those with pCR. These data suggest that plasma exosomal metabolic signatures could be associated with differential NAC outcomes in BC patients and provide insight into the metabolic determinants of NAC response in patients with BC.

Ductal Carcinoma In Situ of Breast: From Molecular Etiology to Therapeutic Management.

Ductal carcinoma in situ (DCIS) makes up a majority of noninvasive breast cancer cases. DCIS is a neoplastic proliferation of epithelial cells within the ductal structure of the breast. Currently, there is little known about the progression of DCIS to invasive ductal carcinoma (IDC), or the molecular etiology behind each DCIS lesion or grade. The DCIS lesions can be heterogeneous in morphology, genetics, cellular biology, and clinical behavior, posing challenges to our understanding of the molecular mechanisms by which approximately half of all DCIS lesions progress to an invasive status. New strategies that pinpoint molecular mechanisms are necessary to overcome this gap in understanding, which is a barrier to more targeted therapy. In this review, we will discuss the etiological factors associated with DCIS, as well as the complexity of each nuclear grade lesion. Moreover, we will discuss the possible molecular features that lead to progression of DCIS to IDC. We will highlight current therapeutic management and areas for improvement.

Female erectile tissues and sexual dysfunction after pelvic radiotherapy: A scoping review.

Sexual function is a vital aspect of human health and is recognized as a critical component of cancer survivorship. Understanding and evaluating the impacts of radiotherapy on female sexual function requires precise knowledge of the organs involved in sexual function and the relationship between radiotherapy exposure and sexual tissue function. Although substantial evidence exists describing the impact of radiotherapy on male erectile tissues and related clinical sexual outcomes, there is very little research in this area in females. The lack of biomedical data in female patients makes it difficult to design studies aimed at optimizing sexual function postradiotherapy for female pelvic malignancies. This scoping review identifies and categorizes current research on the impacts of radiotherapy on normal female erectile tissues, including damage to normal functioning, clinical outcomes of radiation-related female erectile tissue damage, and techniques to spare erectile tissues or therapies to treat such damage. An evaluation of the evidence was performed, and a summary of findings was generated according to Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) Extension for Scoping Reviews guidelines. Articles were included in the review that involved normal female erectile tissues and radiotherapy side effects. The results show that little scientific investigation into the impacts of radiotherapy on female erectile tissues has been performed. Collaborative scientific investigations by clinical, basic, and behavioral scientists in oncology and radiotherapy are needed to generate radiobiologic and clinical evidence to advance prospective evaluation, prevention, and mitigation strategies that may improve sexual outcomes in female patients.

Regional Nodal Irradiation for Clinically Node-Positive Breast Cancer Patients With Pathologic Negative Nodes After Neoadjuvant Chemotherapy.

INTRODUCTION: Neoadjuvant chemotherapy (NAC) is increasingly used for operable breast cancer (BC). Appropriate radiation therapy (RT) fields (ie, whole breast [WB] ± regional nodal irradiation [RNI]) in patients who were clinically node positive (cN1) but convert to pathologically node negative (ypN0) after NAC are unknown and the subject of the accruing NSABP B-51 trial. We sought to compare outcomes between WB RT with or without RNI following breast conservation and sentinel lymph node biopsy (SLNB) alone in cN1, ypN0 women following NAC. PATIENTS AND METHODS: We identified all BC patients with cN1, ypN0 who underwent NAC followed by lumpectomy and SLNB between 2006 and 2015 in the National Cancer Database. RNI utilization was evaluated using Cochran-Armitage test. Overall survival between WB RT alone versus WB + RNI was compared using Kaplan-Meier with and without propensity score-based weighted adjustment and multivariable (MVA) Cox proportional hazards. RESULTS: From 2006 to 2015, RNI use increased from 48.13% to 62.13% (Pfor trend <.001). The 10-year survival for WB alone versus WB + RNI was 83.6% and 79.5%, respectively (P= .14). On MVA analysis, the addition of RNI compared to WB alone was not associated with a survival benefit (WB vs. WB + RNI: hazard ratio 0.80, 95% confidence interval, 0.58-1.11, P= .19). Results were unchanged after propensity score-based adjustment. CONCLUSION: For women with cN1 BC who convert to ypN0 following NAC and breast conserving surgery with SLNB alone, more extensive RNI may not provide a long-term survival benefit. Prospective validation via the NSABP B-51 trial will be essential.

Receipt of Guideline-Concordant Care Does Not Explain Breast Cancer Mortality Disparities by Race in Metropolitan Atlanta.

BACKGROUND: Racial disparities in breast cancer mortality in the United States are well documented. Non-Hispanic Black (NHB) women are more likely to die of their disease than their non-Hispanic White (NHW) counterparts. The disparity is most pronounced among women diagnosed with prognostically favorable tumors, which may result in part from variations in their receipt of guideline care. In this study, we sought to estimate the effect of guideline-concordant care (GCC) on prognosis, and to evaluate whether receipt of GCC modified racial disparities in breast cancer mortality. PATIENTS AND METHODS: Using the Georgia Cancer Registry, we identified 2,784 NHB and 4,262 NHW women diagnosed with a stage I-III first primary breast cancer in the metropolitan Atlanta area, Georgia, between 2010 and 2014. Women were included if they received surgery and information on their breast tumor characteristics was available; all others were excluded. Receipt of recommended therapies (chemotherapy, radiotherapy, endocrine therapy, and anti-HER2 therapy) as indicated was considered GCC. We used Cox proportional hazards models to estimate the impact of receiving GCC on breast cancer mortality overall and by race, with multivariable adjusted hazard ratios (HRs). RESULTS: We found that NHB and NHW women were almost equally likely to receive GCC (65% vs 63%, respectively). Failure to receive GCC was associated with an increase in the hazard of breast cancer mortality (HR, 1.74; 95% CI, 1.37-2.20). However, racial disparities in breast cancer mortality persisted despite whether GCC was received (HRGCC: 2.17 [95% CI, 1.61-2.92]; HRnon-GCC: 1.81 [95% CI, 1.28-2.91] ). CONCLUSIONS: Although receipt of GCC is important for breast cancer outcomes, racial disparities in breast cancer mortality did not diminish with receipt of GCC; differences in mortality between Black and White patients persisted across the strata of GCC.