Breast Cancer-specific Mortality Research Articles

Persistent Neighborhood Poverty and Breast Cancer Outcomes

Patients with breast cancer residing in socioeconomically disadvantaged communities often face poorer outcomes (eg, mortality) compared with individuals living in neighborhoods without persistent poverty. To examine persistent neighborhood poverty and breast tumor characteristics, surgical treatment, and mortality. A retrospective cohort analysis of women aged 18 years or older diagnosed with stage I to III breast cancer between January 1, 2010, and December 31, 2018, and followed up until December 31, 2020, was conducted. Data were obtained from the Surveillance, Epidemiology, and End Results Program, and data analysis was performed from August 2023 to March 2024. Residence in areas affected by persistent poverty is defined as a condition where 20% or more of the population has lived below the poverty level for approximately 30 years. All-cause and breast cancer-specific mortality. Among 312 145 patients (mean [SD] age, 61.9 [13.3] years), 20 007 (6.4%) lived in a CT with persistent poverty. Compared with individuals living in areas without persistent poverty, patients residing in persistently impoverished CTs were more likely to identify as Black (8735 of 20 007 [43.7%] vs 29 588 of 292 138 [10.1%]; P < .001) or Hispanic (2605 of 20 007 [13.0%] vs 23 792 of 292 138 [8.1%]; P < .001), and present with more-aggressive tumor characteristics, including higher grade disease, triple-negative breast cancer, and advanced stage. A higher proportion of patients residing in areas with persistent poverty underwent mastectomy and axillary lymph node dissection. Living in a persistently impoverished CT was associated with a higher risk of breast cancer-specific (adjusted hazard ratio [AHR], 1.10; 95% CI, 1.03-1.17) and all-cause (AHR, 1.13; 95% CI, 1.08-1.18) mortality. As early as 3 years following diagnosis, mortality risks diverged for both breast cancer-specific (rate ratio [RR], 1.80; 95% CI, 1.68-1.92) and all-cause (RR, 1.62; 95% CI, 1.56-1.70) mortality. In this cohort study of women aged 18 years or older diagnosed with stage I to III breast cancer between 2010 and 2018, living in neighborhoods characterized by persistent poverty had implications on tumor characteristics, surgical management, and mortality.

RecurIndex-Guided postoperative radiotherapy with or without Avoidance of Irradiation of regional Nodes in 1–3 node-positive breast cancer (RIGAIN): a study protocol for a multicentre, open-label, randomised controlled prospective, phase III trial

IntroductionPostoperative radiotherapy in patients with breast cancer with one to three lymph node metastases, particularly within the pT1–2N1M0 cohort with a low clinical risk of local–regional recurrence (LRR), has incited...

Social networks, social determinants, and mortality: Western New York Exposures and Breast Cancer study.

There are few studies of social support and other social determinants of health after breast cancer diagnosis and their associations with mortality; results have been inconclusive. Further, it is not known if observed associations are specific to women with breast cancer diagnosis or if associations would be similar among healthy women. Women with incident, pathologically confirmed invasive breast cancer, stage I-IV (n = 1012), and healthy frequency age-matched participants (n = 2036) answered a social support questionnaire in prospective follow-up of a population-based case-control study, the Western New York Exposures and Breast Cancer Study. At interview, all participants were aged 35-79 years and resident of 2 counties in Western New York State. Mortality status was ascertained from the National Death Index. Participants were queried regarding the number of their close friends, frequency of seeing them, household size, household income, and marital status. Hazard ratios (HRs) and 95% confidence intervals (CIs) for breast cancer-specific mortality (breast cancer women only) and all-cause mortality were estimated. Lower household income was associated with higher all-cause mortality among women diagnosed with breast cancer (HR = 2.48, 95% CI = 1.24 to 4.97) and similarly among the healthy women (HR = 2.63, 95% CI = 1.25 to 5.53). Number and frequency of seeing friends, marital status, and household size were not associated with mortality, either among breast cancer patients or among healthy women. Among those diagnosed with breast cancer and healthy women, lower income was associated with more than twice the mortality. Marital status, household size, and number or frequency of meeting friends were not associated with survival.

Ovarian function recovery in breast cancer patients receiving adjuvant anastrozole treatment: updated results from the phase 3 DATA trial

Abstract Purpose Patients with chemotherapy-induced ovarian function failure (CIOFF) may experience ovarian function recovery (OFR). Earlier, we showed that OFR during treatment with anastrozole impacted the prognosis of hormone receptor-positive (HR+) breast cancer (BC) patients with CIOFF. Here, we present the long-term follow-up results. Methods Postmenopausal women with HR+ BC who were 45–57 years of age and received chemotherapy were identified from the phase 3 DATA study (NCT00301457) on the extended use of anastrozole. Eligible patients were categorised into two groups: patients with CIOFF and definitely postmenopausal patients. Patients with CIOFF were monitored for OFR. Disease-free survival (DFS), distant recurrence-free survival (DRFS), and overall survival (OS) were compared between patients with OFR and patients without OFR using multivariable Cox regression analyses, including OFR as a time-dependent covariate. BC-specific mortality (BCSM) was compared between groups using the Fine and Gray method. Results This study included 656 patients: 395 patients with CIOFF and 261 definitely postmenopausal patients. OFR occurred in 39 (12%) of 329 patients with CIOFF who were monitored for OFR. The median follow-up time was 13.3 years. Patients with OFR experienced a deterioration in DFS (hazard ratio (HR) = 1.54; 95% confidence interval (CI) 0.85–2.81), DRFS (HR = 1.51; 95% CI 0.73–3.11), OS (HR = 1.64; 95% CI 0.75–3.55), and BCSM (subdistribution HR = 1.98; 95% CI 0.84–4.63) when compared with patients without OFR. Conclusion In patients with CIOFF, OFR during treatment with anastrozole was associated with a deterioration in BC outcomes. These findings underscore the importance of adequate ovarian function suppression in this subgroup of patients.

Neighborhood Deprivation and Breast Cancer Mortality Among Black and White Women

Neighborhood deprivation has been associated with increased breast cancer mortality among White women, but findings are inconsistent among Black women, who experience different neighborhood contexts. Accounting for interactions among neighborhood deprivation, race, and other neighborhood characteristics may enhance understanding of the association. To investigate whether neighborhood deprivation is associated with breast cancer mortality among Black and White women and whether interactions with rurality, residential mobility, and racial composition, which are markers of access, social cohesion, and segregation, respectively, modify the association. This population-based cohort study used Georgia Cancer Registry (GCR) data on women with breast cancer diagnosed in 2010 to 2017 and followed-up until December 31, 2022. Data were analyzed between January 2023 and October 2023. The study included non-Hispanic Black and White women with invasive early-stage (I-IIIA) breast cancer diagnosed between 2010 and 2017 and identified through the GCR. The Neighborhood Deprivation Index (NDI), assessed in quintiles, was derived through principal component analysis of 2011 to 2015 block group-level American Community Survey (ACS) data. Rurality, neighborhood residential mobility, and racial composition were measured using Georgia Public Health Department or ACS data. The primary outcome was breast cancer-specific mortality identified by the GCR through linkage to the Georgia vital statistics registry and National Death Index. Cox proportional hazards regression was used to estimate age-adjusted and multivariable-adjusted hazard ratios (HRs) and 95% CIs for the association between neighborhood deprivation and breast cancer mortality. Among the 36 795 patients with breast cancer (mean [SD] age at diagnosis, 60.3 [13.1] years), 11 044 (30.0%) were non-Hispanic Black, and 25 751 (70.0%) were non-Hispanic White. During follow-up, 2942 breast cancer deaths occurred (1214 [41.3%] non-Hispanic Black women; 1728 [58.7%] non-Hispanic White women). NDI was associated with an increase in breast cancer mortality (quintile 5 vs 1, HR, 1.36; 95% CI, 1.19-1.55) in Cox proportional hazards models. The association was present only among non-Hispanic White women (quintile 5 vs 1, HR, 1.47; 95% CI, 1.21-1.79). Similar race-specific patterns were observed in jointly stratified analyses, such that NDI was associated with increased breast cancer mortality among non-Hispanic White women, but not non-Hispanic Black women, irrespective of the additional neighborhood characteristics considered. In this cohort study, neighborhood deprivation was associated with increased breast cancer mortality among non-Hispanic White women. Neighborhood racial composition, residential mobility, and rurality did not explain the lack of association among non-Hispanic Black women, suggesting that factors beyond those explored here may contribute to breast cancer mortality in this racial group.

Updated SEER database study of 21-gene assay to assess breast cancer–specific mortality and benefit of chemotherapy by race and ethnicity.

533 Background: In randomized studies (NSABP B-20, SWOG 8814, TAILORx, RxPONDER), the predictive effect of the 21-gene Breast Recurrence Score assay (RS) on chemotherapy (CT) benefit has been evaluated in patients with node-negative (N0) and node-positive (N+) breast cancer. Retrospective analyses of TAILORx and RxPONDER demonstrated differences in outcome by racial/ethnic groups (RG); however, there were no differences in CT benefit for any of the clinical outcome measures. In this study we characterized the association between the RS result and breast cancer-specific mortality (BCSM) and chemotherapy benefit in BCSM in RG in the recently updated, population-based SEER registries. Methods: Eligible patients were from the SEER 17 registries, November 2022 submission, and had non-metastatic, hormone receptor-positive, HER2-negative, node negative (N0) breast cancer diagnosed between 2006 and 2019 with a RS result. Analyses were weighted using the inverse of estimated propensity of using CT (yes vs. none/unknown). Prognosis was ascertained by estimating breast cancer specific survival (BCSS) at 9 years among patients with CT recorded as none/unknown by RG. The log-rank test was used to compare BCSM by RG. Multivariable Cox models, including RS result (26-100 vs. 0-25) x CT interaction, were used to assess whether RS result was predictive of CT benefit. Analyses were performed in the overall cohort and in Hispanic (H), non-Hispanic Asian and Pacific Islander (NHAPI), non-Hispanic Black (NHB), and non-Hispanic White (NHW) RGs. Results: There were 145,642 eligible patients and 3,212 breast cancer deaths. Median follow-up was 68 months. NHB patients had higher median RS result and CT usage than other groups (p &lt; .001). In N0 patients, higher RS result was associated with lower 9-year BCSS, both overall and by race/ethnicity (p &lt; .001). In Cox multivariable models (Table), the interaction between RS result by CT was significant among all N0 patients (p &lt; .001) and in NHB patients (p = 0.005), NHW patients (p = 0.002), and H patients (p = 0.019), but not in NHAPI patients (p = 0.766). Analyses of patients with N+ disease and more detailed analysis of CT benefit according to RS results by RG are underway and will also be presented. Conclusions: Real-world evidence from the SEER registries in over 145,000 patients confirms the 21-gene assay is prognostic for BCSS in all groups by race and ethnicity. The RS result was predictive of CT benefit in N0 patients overall and in Hispanic, NHB, and NHW patients, but not in NHAPI patients in this analysis. [Table: see text]

Patterns of screening and access to care in women diagnosed with breast cancer in a safety-net system.

1531 Background: Screening mammography reduces breast cancer specific mortality by allowing diagnosis at an earlier stage. Inconsistent guidelines and limitations in access to primary care are among factors that affect screening uptake. In this study, we reviewed patient characteristics, access to care, and uptake of screening mammogram (SMMG) prior to a breast cancer diagnosis at a safety-net system. Methods: Parkland Health (PH) is the safety-net system for Dallas County and is affiliated with the University of Texas Southwestern Simmons Comprehensive Cancer Center. Electronic medical records of patients with a new invasive breast cancer diagnosis between 2018 and 2019 at PH were reviewed and data on demographics and clinical presentation were collected. Patients were categorized based on SMMG uptake prior to their cancer diagnosis: never-screened, ever-screened (SMMG &gt; 2 years prior to diagnosis) and recent-screened (SMMG within 2 years of diagnosis). Results: A total of 468 new breast cancer cases were identified (48.7% Hispanic; 32.9% Black). Of these, 12.2% were younger than 40 and 27.8% were 40-49. Payer mix included 64.7% uninsured and 34.8% Medicare/Medicaid. Half of the patients (50.6%) never had SMMG. Never-screened rate was higher among younger patients (98.2% in &lt; 40; 53.8% in 40-49; and 39.4% in &gt;50; p &lt; 0.0001). Only 25.2% (118/468) of the patients had a SMMG within 2 years prior to their diagnosis. Among patients aged &gt;40, 44.0% (181/411) were never-screened and 28.7% (118/411) were recent-screened. Screen-detection rate among patients &gt;40 was 40.1% (165/411), of whom 22 (13.3% of screen-detects) were diagnosed with cancer on their first ever SMMG. Race/ethnicity, insurance status, and positive family history of cancer were not significantly different between never, ever, and recent-screened patients. Screening uptake correlated with nodal status, tumor size and stage at diagnosis. Patients who had a prior encounter at Parkland were more likely to have a SMMG. Patients established with Parkland primary care at diagnosis were more likely to have early-stage disease. In patients &lt; 40, 24.6% presented with stage IV disease at diagnosis and 57.9% did not have a primary care provider. A positive family history of breast/ovarian cancer or any cancer was noted in 38.6% and 57.9% of patients &lt; 40, respectively. Conclusions: In the cohort presented here, 27.8% of patients were between age 40-49, reflecting the impact of a gap in the guideline, which is now addressed in the most recent iteration of USPSTF guidelines. Connecting ED users to primary care, identifying higher risk individuals through family history, and increasing SMMG rate in the primary care setting are among strategies to reduce the rate of late-stage diagnosis of breast cancer, particularly among vulnerable patient populations.

Ductal carcinoma in situ and cause-specific mortality among younger and older postmenopausal women: the Women's Health Initiative.

Whether DCIS is associated with higher breast cancer-specific and all-cause mortality is unclear with few studies in older women. Therefore, we examined DCIS and breast cancer-specific, cardiovascular (CVD)-specific, and all-cause mortality among Women's Health Initiative (WHI) Clinical Trial participants overall and by age (< 70 versus ≥ 70 years). Of 68,132 WHI participants, included were 781 postmenopausal women with incident DCIS and 781 matched controls. Serial screening mammography was mandated with high adherence. DCIS cases were confirmed by central medical record review. Adjusted multivariable Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI). Kaplan Meier (KM) plots were used to assess 10-year and 20-year mortality rates. After 20.3 years total, and 13.2 years median post-diagnosis follow-up, compared to controls, DCIS was associated with higher breast cancer-specific mortality (HR 3.29; CI = 1.32-8.22, P = 0.01). The absolute difference in 20-year breast cancer mortality was 1.2% without DCIS and 3.4% after DCIS, log-rank P = 0.026. Findings were similar by age (< 70 versus ≥ 70 years) with no interaction (P interaction = 0.80). Incident DCIS was not associated with CVD-specific mortality (HR 0.77; CI-0.54-1.09, P = 0.14) or with all-cause mortality (HR 0.96; CI = 0.80-1.16, P = 0.68) with similar findings by age. In postmenopausal women, incident DCIS was associated with over three-fold higher breast cancer-specific mortality, with similar findings in younger and older postmenopausal women. These finding suggest caution in using age to adjust DCIS clinical management or research strategies.

Breast cancer risk assessment for prescription of menopausal hormone therapy in women with a family history of breast cancer: an epidemiological modelling study.

Menopausal hormone therapy (MHT) can alleviate menopausal symptoms but has been associated with an increased risk of breast cancer. MHT prescription should be preceded by individualised risk/benefit evaluation; however, data outlining the impact of family history alongside different MHT therapeutic approaches are lacking. To quantify the risks associated with MHT use in women with varying breast cancer family histories of developing and dying from breast cancer. An epidemiological modelling study for women in England using the BOADICEA breast cancer prediction model and data relating to MHT use and breast cancer risk taken from research by the Collaborative Group on Hormonal Factors in Breast Cancer. The risk of developing and dying from breast cancer between the ages of 50 and 80 years was modelled in women with four different breast cancer family history profiles: 'average', 'modest', 'intermediate', and 'strong' by using 1) background risks of breast cancer by age and family history, 2) relative risks for breast cancer associated with MHT use, and 3) 10-year breast cancer-specific net mortality rates. This study modelled use of combined oestrogen-progestogen MHT (cyclical or continuous) and oestrogen-only MHT. For a woman of 'average' family history taking no MHT, the cumulative breast cancer risk (age 50-80 years) is 9.8%, and the risk of dying from the breast cancer is 1.7%. In this model, 5 years' exposure to combined-cyclical MHT (age 50-55 years) was calculated to increase these risks to 11.0% and 1.8%, respectively. For a woman with a 'strong' family history taking no MHT, the cumulative breast cancer risk is 19.6% (age 50-80 years), and the risk of dying from the breast cancer is 3.2%. With 5 years' exposure to MHT (age 50-55 years), this model showed that these risks increase to 22.4% and 3.5%, respectively. In this model, both family history and MHT are associated with increased risk of breast cancer. Estimates of the risks of breast cancer associated with MHT for women with different family histories can be used to support decision making around MHT prescription for women experiencing menopausal symptoms.

Statin use and risks of breast cancer recurrence and mortality.

Preclinical evidence suggests improved breast cancer survival associated with statin use, but findings from observational studies are conflicting and remain inconclusive. The objective of this study was to assess the association between statin use after cancer diagnosis and cancer outcomes among breast cancer patients. In this retrospective cohort study, 38,858 women aged ≥66 years who were diagnosed with localized and regional stage breast cancer from 2008 through 2017 were identified from the linked Surveillance, Epidemiology, and End Results Medicare database. Statin use was ascertained from Medicare Part D pharmacy claims data. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between post-diagnosis statin use and risks of breast cancer recurrence and breast cancer-specific mortality. Over a median follow-up of 2.9 years for recurrence and 3.7 years for mortality, 1446 women experienced a recurrence, and 2215 died from breast cancer. The mean duration of post-diagnosis statin use was 2.2 years. Statin use post-diagnosis was not associated with recurrence risk (HR, 1.05; 95% CI, 0.91-1.21), but was associated with a reduced risk of cancer-specific mortality (HR, 0.85; 95% CI, 0.75-0.96). The reduction was more pronounced in women with hormone receptor-positive/human epidermal growth factor receptor 2-negative breast cancer (HR, 0.71; 95% CI, 0.57-0.88). These findings suggest that post-diagnosis statin use is associated with improved cancer-specific survival in women with breast cancer and should be confirmed in randomized trials of statin therapy in breast cancer patients.

Dampak Oforektomi terhadap Kualitas Hidup dan Fungsi Seksual Orang dengan Kanker Payudara

This study aims to identify the impact of orthorectomy on breast cancer patients, especially on their quality of life and sexual function. We conducted a systematic review adhering to PRISMA guidelines, searching articles from PubMed, ProQuest, Embase, and ScienceDirect databases from inception to March 2024. The search terms used were "oophorectomy", "quality of life", "sexual function", and "breast cancer". Results from 8 articles showed that oophorectomy can negatively affect quality of life, especially in physical and psychosocial aspects, and can be associated with sexual dysfunction. Ophorectomy was also associated with significant reductions in all-cause mortality and breast cancer-specific mortality. In conclusion, this study shows about ooforectomy have a significant impact on quality of life and sexual function of women, especially on physical and psychosocial aspects. Although, these impacts do not entirely affect quality of life, Keywords: Oophorectomy, Breast Cancer, Quality of Life, Sexual Dysfunction

Abstract PO2-25-08: Role of social isolation and support on all-cause and breast cancer specific mortality among women with breast cancer: The Western New York Exposures and Breast Cancer (WEB) Study

Abstract Background: Studies of associations of social support with mortality among women diagnosed with breast cancer have been inconclusive. Further, there have been little study of related factors such as marital status, housing, and income, nor of differential impact by treatment received (chemotherapy, radiation, or hormonal therapy). Methods: Women with incident, pathologically confirmed invasive breast cancer, stage I-IV, answered a social support questionnaire data (n=1015) in a population-based study, the Western New York Exposures and Breast Cancer (WEB) Study. Patients were queried regarding the number of their close friends, the number of people with whom they lived with, their income, education, and marital status. Hazard ratios (HR) and 95% confidence intervals (CI) for all-cause and breast cancer-specific mortality were estimated with Cox proportional hazards models. Associations were also examined within strata of treatment type received. Results: Median follow up time was 18.5 yrs, 449 died of which 279 deaths were from breast cancer. Out of 1015 patients, 98 patients reported 0-1 friends while 917 reported 2 or more friends. The crude association of social isolation, defined as reporting no or one close friend, was significantly associated with higher all-cause mortality with HR 1.57 (95% CI 1.19-2.07) (p=0.0014). Older age (62 yrs vs. 57 yrs), fewer years of education (12.5 yrs vs. 13.5 yrs), longer smoking history (17 pack years vs. 10.7 pack years), higher percentage of non-white population (15.3% vs. 7.52%), lower income (20.7% vs. 7.2%), living alone (45.9% vs. 21.9%), post-menopausal status (83.7% vs. 70.7%), lower receipt of chemotherapy (32.3% vs. 44.8%), higher receipt of hormone replacement therapy (43.9% vs. 37.0%), high blood pressure (53.6% vs. 33.8%), high blood cholesterol (45.8% vs. 34.1%), more likelihood of being divorced/separated, widowed, never married (20.8% v. 12.8%, 19.8% vs. 15.2%, 13.5% vs. 7.8%) were significantly associated with social isolation. After controlling for these variables, there was no association between social isolation and all-cause mortality, HR 1.14 (95% CI, 0.78-1.66). Being widowed (HR 1.53, 95% CI 1.19-1.95), divorced/separated (HR 1.5, 95% CI 1.14-1.99), having lower income (HR 3.58, 95% CI, 1.89-6.77) and lower education (HR 1.07, 95% CI 1.03-1.12) were associated with higher all-cause mortality. In multivariable analyses, only lower income was associated with higher all-cause mortality (HR 2.44, 95% CI 1.16-5.14). There was no association of social isolation, marital status, income, education, or housing with breast cancer specific mortality. There were also no significant associations of marital status, income, social support, or housing with mortality within strata of treatment received. Conclusions: In this population-based study of women who had been diagnosed with breast cancer, social support, measured as the number of friends the breast cancer patient could call on for assistance, was not associated with either all cause or breast cancer mortality. Higher income was associated with lower mortality. Our study focused on social networks; future studies should also analyze emotional domain of social support, that is, perceived social support: feeling encouraged, shared problem-solving etc., which have higher clinical relevance than structural support. Citation Format: Shipra Gandhi, Jing Nie, Archit Patel, Maurizio Trevisan, Kristopher Attwood, Jo L. Freudenheeim. Role of social isolation and support on all-cause and breast cancer specific mortality among women with breast cancer: The Western New York Exposures and Breast Cancer (WEB) Study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-25-08.

Abstract PS18-10: Tumor-Infiltrating Lymphocytes and Breast Cancer Mortality in Racially and Ethnically Diverse Participants of the Northern California Breast Cancer Family Registry

Abstract Purpose: Greater stromal tumor-infiltrating lymphocyte (sTIL) percentage in pre-treatment breast tumor specimens is associated with superior response to neoadjuvant chemotherapy and survival. We hypothesized that sTIL-survival associations vary by race and ethnicity and mediate survival disparities. Patients and Methods: We evaluated pre-treatment percentages of sTILs in deciles for 284 women enrolled in the Northern California Breast Cancer Family Registry and diagnosed with a first primary invasive breast cancer from 1995-2005. We assessed associations of continuous sTIL scores and lymphocyte-predominant breast cancer (LPBC, defined as ≥50% lymphocytic infiltration of tumor stroma or cell nests) with clinical and epidemiologic characteristics using regression analysis and with breast cancer-specific mortality (BCM) and overall mortality (OM) using Cox proportional hazards regression. Results: The cohort was diverse (64% from racially and ethnically minoritized populations) with near-complete (98%) germline BRCA1/2 testing and long-term follow-up (average 16.2 years, range: 1.3-26.7). In multivariable analyses, higher sTIL score was associated with reduced BCM [LPBC versus non-LPBC: HR=0.44 (95% confidence interval 0.20-0.98); and per decile increase in sTIL score: HR=0.80 (0.69-0.93)], with the strongest association in the subset of patients with hormone receptor-negative disease [HR=0.71 (0.57-0.88) and HR=0.37 (0.14-0.94), respectively]. While there was no significant difference in sTIL score between racial and ethnic groups, the continuous sTIL-survival association was statistically significant among non-Hispanic White [HR=0.73 (0.57-0.94)] and Asian American [HR=0.56 (0.35-0.89)] women but was not seen among African American and Hispanic women. Conclusion: We identified novel sTIL-BCM differences by race and ethnicity, with better survival associated with sTIL enrichment among non-Hispanic White and Asian American but not among African American or Hispanic women. Additional studies are needed to determine whether survival and particularly the response to immunotherapy are differentially mediated by immune factors between racial and ethnic groups. Multivariable Cox Proportional Hazards Regression Models of Breast Cancer-Specific and Overall Mortality. Citation Format: Julia Ransohoff, Iain Miller, Jocelym Koo, Vishal Joshi, Allison Kurian, Kimberly Allison, Esther John, Melinda Telli. Tumor-Infiltrating Lymphocytes and Breast Cancer Mortality in Racially and Ethnically Diverse Participants of the Northern California Breast Cancer Family Registry [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS18-10.

Abstract PO5-18-02: A Population-Based Analysis of the Impact of Omission of Anthracyclines in the Neoadjuvant Setting on the Risk of Mortality

Abstract Background Most patients with high-risk non-metastatic breast cancer are treated with neoadjuvant chemotherapy (NAC), which includes the administration of anthracyclines. The omission of anthracyclines was shown to be associated with excellent outcomes in selected patients. However, the extent to which anthracyclines are omitted among a population of women treated with NAC and its impact on mortality remain unclear. Objective To investigate the extent to which anthracyclines are omitted among a population of patients with invasive breast cancer treated with NAC and to examine the impact of non-anthracycline NAC on risks of breast cancer-specific and all-cause mortality. Methods We performed a retrospective population-based cohort analysis using patient-level health administrative data. The cohort includes women aged ≥18 years with stage I – III invasive breast cancer diagnosed between January 2012 and December 2020, treated with NAC and surgery. Patients were excluded if they received &amp;lt; 50% of the planned chemotherapy regimen, had bilateral breast cancer and/or a previous malignancy. The exposure of interest was anthracycline versus non-anthracycline NAC regimen. The primary and secondary endpoints were breast cancer-specific mortality and overall (all-cause) mortality. Multivariable Cox proportional hazards models adjusted by propensity score, and clinical/pathologic variables including a measure of comorbidity was performed to examine impact of omission of anthracyclines on outcomes. Cumulative incidence curves were generated to calculate the 5-year cumulative incidence of breast cancer and all-cause mortality for the whole cohort and in subset analyses, stratified by stage and receptor subtype. Results The cohort includes 4,180 women. Median follow was 62 months (IQR 44-85) and median age was 51 years (IQR 43-60). Most patients had low co-morbidities (96.0%), Stage II (44.1%) or Stage III (47.7%) disease, underwent mastectomy (72.6%), had axillary node dissection (64.4%) and received post-operative radiotherapy (88.8%). 279 (6.7%) individuals were treated with a non-anthracycline NAC and 3,901 (93.3 %) received an anthracycline NAC. Women who received non-anthracycline NAC were older (median 62 years vs. 50 years; p&amp;lt; 0.001), more likely to have stage I-II disease (77.0% vs. 51.3%; p&amp;lt; 0.001), and more likely to have triple-negative breast cancer (TNBC) (14.0% vs. 24.4%; p&amp;lt; 0.001) than those who received anthracyclines.On propensity adjusted multivariable analysis, factors associated with an increased risk of BC mortality include Stage III (HR 9.3, 95%CI 4.5 - 19.2, p&amp;lt; 0.0001) or stage II at presentation (HR 2.57 95% CI 1.24, 5.34, p=.01) (ref: stage I) or triple negative subtype (HR 3.7 95% CI 3.03, 4.51, p&amp;lt; .0001) (ref: hormone positive/HER2-). There was no significant difference in the relative risks of BC death (HR 0.8, 95% CI 0.5-1.27) or all-cause mortality (HR 0.85, 95% CI 0.60-1.21) for patients selected for treatment without anthracyclines compared to those treated with anthracyclines.Overall, among individuals selected for treatment without or with anthracycline NAC there was no significant difference in the 5-year cumulative incidence of BC (15.4% vs 10.5%, P=.05) or all-cause mortality (16.4% vs 11.9%, P=.07). However, the 5-year cumulative incidence of BC specific death (31.8% vs 16.5%, p=.03) and 5-year cumulative incidence of all-cause death (31.8% vs. 18.2%, p=.06) was higher among 420 women with HER2+ Stage III breast cancer who received non-anthracycline versus anthracycline-based chemotherapy. No difference was observed for other subgroups. Conclusions The omission of anthracyclines in NAC for individuals with stage III HER2+ breast cancer was associated with higher cumulative risks of breast cancer and all-cause mortality but no difference was observed for other subgroups. Further research is warranted to better understand in whom anthracyclines can be safely omitted. Citation Format: Danilo Giffoni M. M. Mata, Rinku Sutradhar, Matthew Castelo, Lena Nguyen, Danielle Rodin, Ezra Hahn, Omolara Fatiregun, Cindy Fong, Sabina Trebinjac, Andrea Eisen, Lawrence Paszat, Katarzyna Jerzak, Eileen Rakovitch. A Population-Based Analysis of the Impact of Omission of Anthracyclines in the Neoadjuvant Setting on the Risk of Mortality [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-18-02.

Abstract PO2-02-04: The Impact of Statins on Breast Cancer Specific Mortality in a Diverse Patient Population with Stage I-III Hormone Receptor Positive, HER2 Negative Breast Cancer

Abstract Hormone receptor-positive (HR+), HER2 negative (HER2−) breast cancer has a long-term risk of recurrence, compared with other breast cancer subtypes, which ultimately impacts mortality outcomes. Although adjuvant endocrine therapy plays an integral role in risk reduction, disparities persist—with Black women experiencing higher mortality rates compared to White women. Multiple studies have demonstrated that statin use can lead to a reduction in breast cancer mortality, but there is limited information in relation to the impact of statins among diverse patient populations in the United States. To assess whether statin use is associated with an improvement in breast cancer-specific mortality (BCSM), we conducted a large, observational study in women aged 66 and older diagnosed with Stage I–IIIC HR+, HER2- breast cancer between 2013 and 2017. We identified eligible women using the SEER-Medicare database and linked them to the BRIDGE (BReast cancer Investigation of Disparities in GEorgia) cohort, a survivorship cohort of the Georgia Cancer Registry. Patients needed to be continuously enrolled in Medicare Parts A, B, and D in the 12 months following a breast cancer diagnosis. We used Cox proportional hazards models to estimate the impact of statin use within 12 months of diagnosis on BCSM with adjustment for age, stage, and race using multivariable-adjusted hazard ratios (HRs). A total of 2483 participants were identified, and of those, 303 (12.2%) were statin users, 383 (15.4%) were non-Hispanic Black women, and 1564 (63%) resided in census tract with greater than or equal to 10% poverty levels at the time of diagnosis. Distribution of age, stage, and race were similar between statin and non-statin users. Of the statin users, 41/303 (13.5%) were non-Hispanic Black women. The majority of statin users were prescribed lipophilic statins alone (169; 55.8%), and atorvastatin was the most commonly prescribed statin. There was no association between statin use and BCSM (HR 1.09; 95% CI 0.62-1.90) in the multivariable-adjusted model. Although preliminary results suggest that there is no association between statin use and BCSM among women with Stage I–IIIC HR+, HER2− breast cancer, further analyses are planned to explore statin use as a time-varying exposure, which may provide additional insights into the potential relationship between statin use and BCSM. In addition, analyses examining potential heterogeneity by race, tumor and treatment characteristics, and comorbidities are forthcoming. Given the low cost and relative accessibility of statins, we anticipate these findings will inform the clinical management of women with operable breast cancer, increasing parity in outcomes and potentially narrowing race disparities. Citation Format: Ruth Sacks, Maya Bliss, Micah Streiff, Leah Moubadder, Maret Maliniak, Tsion Armidie, Lindsay Collin, Kevin Kalinsky, Lauren McCullough. The Impact of Statins on Breast Cancer Specific Mortality in a Diverse Patient Population with Stage I-III Hormone Receptor Positive, HER2 Negative Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-02-04.

Abstract PO3-09-06: Role of Obesity-Related Biomarkers on Mortality Among Black Breast Cancer Survivors in the Women’s Circle of Health Followup Study

Abstract Background: Central obesity and higher adiposity have been recently associated with higher all-cause and breast cancer-specific mortality in Black breast cancer survivors participating in the Women’s Circle of Health Followup Study. Adipose tissue is a dynamic organ producing adipocytokines, including leptin, adiponectin, adipsin, resistin, lipocalin-2/NGAL, plasminogen-activator inhibitor type 1 (PAI-1) and CXCL11, TNFα, and IL-6, which modulate inflammatory markers in obesity, including the release of proinflammatory C-reactive protein (CRP). These circulating biomarkers play important roles linking obesity with insulin resistance, hyperinsulinemia, chronic inflammation, and altered immunity, which may impact overall and breast cancer mortality. The goal of this analysis was to determine if circulating adipocytokines and obesity-related biomarkers of systemic inflammation are associated with breast cancer and overall survival in Black breast cancer survivors. Methods: Circulating biomarkers were assayed for 460 Black breast cancer survivors who provided a blood sample 2 years post-diagnosis in the Women’s Circle of Health Followup Study, a population-based cohort of Black breast cancer survivors in New Jersey enrolled within 12 months of diagnosis. Associations between biomarkers (by tertiles) and overall survival were assessed using multivariable Cox regression models. Breast cancer specific survival was assessed based on competing risk analyses using the Fine and Gray subdistribution hazard model. Multivariable models were adjusted for age, body mass index as a measure of overall adiposity, education, menopausal status, stage, grade, subtype, and chemotherapy, hormonal therapy, and radiation treatments received. All tests were two-sided at Analyses were conducted at P=0.05. Results: In multivariable analyses, lipocalin-2, CXCL11, and CRP, biomarkers of adipose tissue inflammation closely related to insulin resistance, were associated with worse overall but not breast cancer specific survival. Compared to women in the lowest tertile of lipocalin-2, women in the highest tertile had a 3-fold increased risk of dying from any cause (T3 vs T1, HR=3.08, 95% CI: 1.29-7.39, p= 0.004) and a ~2-fold increased risk of dying from breast cancer, which was not statistically significant (HR= 1.84, 95% CI: 0.59-5.79, p=0.30). Similarly, women in the highest tertile of CXCL11 were at 2-fold increased risk of dying of any cause (HR: 2.10, 95% CI: 0.96-4.57, p=0.06) but no associations were observed with risk of dying from breast cancer (HR:1.31, 0.42-4.13, p=0.64). Circulating CRP, as a marker of systemic inflammation, was also associated with worse overall survival (T3 vs T1 HR: 2.51, 95% CI: 1.07-5.89, p=0.03), showing a borderline significant association with increased breast cancer specific survival (T3 vs T1 HR: 4.32, 95% CI: 0.87-21.38, p=0.07). No associations with overall or breast cancer specific mortality were observed for any of the other adipocytokines examined. Conclusion: In this population-based cohort study of Black breast cancer survivors, biomarkers associated with adipose tissue related inflammation and insulin resistance were associated with reduced overall survival. Relationships with breast cancer survival were not significant, possibly due to limited sample size. Citation Format: Shipra Gandhi, Chi-Chen Hong, Anthony George, Kristopher Attwood, Bo Quin, Nur Zeinomar, Yong Lin, Christine Ambrosone, Kitaw Demissie, Elisa Bandera. Role of Obesity-Related Biomarkers on Mortality Among Black Breast Cancer Survivors in the Women’s Circle of Health Followup Study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-09-06.

Abstract PO5-25-10: Clinical and Epidemiologic Significance of HER2-Low Expression in Breast Cancer in the Pathways Study

Abstract Background: A subset of breast cancers (BC) typically classified as HER2-negative do express low levels of the protein and can be responsive to targeted therapy trastuzumab-deruxtecan. It is unclear if HER2-low tumors have a biology distinct from that in HER2 negative BC. The goal of this study was to evaluate the clinical and epidemiologic features of tumors with HER2-low expression compared with those classified as HER2-negative in a large population study. Material and methods: The Pathways Study is a prospective multi-ethnic cohort study of women with BC enrolled between 2006-2013 within Kaiser Permanente Northern California (KPNC). Breast biomarker results were extracted from pathology reports and underwent centralized pathology review. HER2-low was defined as 1+ or 2+ (negative by in situ hybridization); HER2-negative was defined as 0+. Other data were collected by self-report or extraction from electronic health records at the KPNC cancer registry, including BC risk factors, tumor characteristics [AJCC stage, ER/PR positive or negative status], treatment modality (chemotherapy, radiation therapy, hormonal therapy, and type of surgery), and survival outcomes [recurrence free survival (RFS), breast cancer specific mortality (BCSM), and overall survival (OS)]. The clinical and epidemiologic variables were tested in association with HER2 status (low/negative) by t-tests. Associations of HER2-low with survival outcomes were calculated by proportional hazards regression. Women were included in this analysis if they had a documented HER2 value that was not classified as HER2-positive. Results: Of the 2,200 eligible cases, 1,295 (57.2%) had tumors that were HER2-low. Hormone receptors (HR) were positive in 1,956 (88.9%) cases. HER2-low expression was observed more often in HR-positive cases than in HR-negative, 1,144 (58.4%) vs. 115 (47.1%), respectively (p=.0005). Patients with HER2-low tumors were less likely than those with HER2-negative BC to have family history: 232 of 1259 (18.6%) vs. 214 of 941 (22.8%), respectively (p=.015). This difference was true for patients with HR-positive tumors but not for HR-negative. HER2-low expression appeared to be more common in Asian patients in the HR-negative group than in patients from any other race or ethnicity group. In the HR-negative group, patients with HER2-low had better OS, BCSM, and RFS (p=.019, .014, and .034, respectively) than those with HER2-negative disease. Multivariable analyses were performed for the HR-negative group and adjusted for age at diagnosis, tumor AJCC stage, and type of treatment. Compared with patients with HER2-negative status, patients with HER2-low tumors had lower risk for OS (hazard ratio=0.48, 95% confidence interval: 0.28 to 0.81, p= .006); for RFS (hazard ratio=0.49, 95% confidence interval: 0.27 to 0.90, p= .021); and for BCSM (hazard ratio=0.36, 95% confidence interval: 0.17 to 0.76, p= .007). In analyses stratified by race and ethnicity and controlled for age at diagnosis, AJCC stage and treatment type, Black patients with HER2-low tumors had lower risk for RFS (hazard ratio=0.44, 95% confidence interval: 0.21 to 0.94, p= .035) compared with patients with HER2-negative tumors. Conclusions: In this large prospective study with well annotated epidemiologic, clinical, and outcome data, we observed some clinical and epidemiologic differences between HER2-low and HER2-negative patients, raising the possibility that HER2-low might be a unique biologic entity. Citation Format: Thaer Khoury, Rochelle Payne Ondracek, Song Yao, Lucas Mendocino, Warren Davis, Angela Omilian, Marilyn Kwan, Janise Roh, Lia D'Addario, Emily Valice, Daniel Fernandez, Isaac Ergas, Christine Ambrosone, Lawrence Kushi. Clinical and Epidemiologic Significance of HER2-Low Expression in Breast Cancer in the Pathways Study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-25-10.

Abstract PO3-03-02: Effect of Surgery on Breast Cancer-Specific Mortality in Elderly Patients with Hormone Receptor-Positive, HER2-Negative Breast Cancer

Abstract Background: The number of elderly patients with breast cancer has been increasing in Japan. Although standard treatment including surgery is desirable if the expected life expectancy is sufficient, not all elderly patients with breast cancer are eligible for surgery due to frailty and comorbidities. Endocrine therapy (ET) alone is an alternative option if surgery is not considered adequate in patients with hormone receptor-positive breast cancer. We evaluated whether ET alone was associated with inferior overall and breast cancer-specific survival compared to standard treatment including surgery in elderly patients. Methods: This study included all patients aged 75 years and over who were diagnosed with non-metastatic primary invasive hormone receptor-positive, HER2-negative breast cancer and treated at Hiraka General Hospital from July 2006 to March 2022. Patients were divided as those who received ET alone (ET alone group) and those who received surgery with other therapies (Surgery group). Survival status as on March 31, 2023 and cause of death were determined. Overall survival and breast cancer-specific survival were estimated using the Kaplan–Meier method and compared using the log-rank test. Univariate analysis and multivariate Cox proportional hazards regression model including age, Eastern Cooperative Oncology Group performance status (PS) score, clinical stage, and treatment were used to identify survival-associated factors. Propensity score matching was used to reduce the effect of selection bias on treatment type during survival comparison of the groups. Results: The study cohort comprised 128 patients, including 33 and 95 patients in the ET alone group and Surgery group, respectively. The median ages were 84.6 and 80.4 years in the ET alone group and Surgery group, respectively (p &amp;lt; 0.05). Ten patients (30%) in the ET alone group had poor PS (3 or 4), and no patient in the Surgery group had poor PS (p &amp;lt; 0.01). Also, 24.2%, 54.5%, and 21.2% of the patients in the ET alone group and 48.4%, 43.2%, and 8.4% of the patients in the Surgery group had clinical stage I, II, and III disease at diagnosis, respectively (p &amp;lt; 0.05). Survival status was confirmed in all patients, and the cause of death was confirmed in 52 of the 53 patients who died (98%) during the study period, including 24 and 29 patients in the ET alone group and Surgery group, respectively. Breast cancer was the cause of death in 3 patients (13%) in the ET alone group and 5 patients (17%) in the Surgery group. By univariate analysis, overall survival was significantly better in the Surgery group than in the ET alone group (median, 12.5 vs. 4.1 years; p &amp;lt; 0.0001). Similarly, breast cancer-specific survival was better in the Surgery group than in the ET alone group (p &amp;lt; 0.05). By multivariate Cox proportional hazards regression analysis, age was associated with shorter overall survival time (hazard ratio [HR] 1.07, 95% confidence interval [CI] 1.00–1.15; p = 0.04) and surgery was associated with longer overall survival (HR 0.24, 95% CI 0.12–0.47; p &amp;lt; 0.001). Breast cancer-specific survival was associated with age (HR 1.18, 95% CI 1.03–1.36; p = 0.02) and clinical stage (HR 8.89, 95% CI 1.05–75.5; p &amp;lt; 0.05) but not with treatment (HR 0.66, 95% CI 0.73–5.85; p = 0.71). After propensity score matching, overall survival was significantly better in the Surgery group than in the ET alone group (HR 0.26, 95% CI 0.09–0.73; p = 0.01) whereas breast cancer-specific survival was not significantly different between the two groups (HR 0.82, 95% CI 0.08–8.27; p = 0.86). Conclusion: Even in elderly patients, surgery should be considered if sufficient life expectancy is expected. However, most of the deaths were not related to breast cancer in the present study cohort. Therefore, for elderly patients without sufficient life expectancy, endocrine therapy alone would be an appropriate option. Citation Format: Misako Yatsuyanagi, Tomoyuki Shimada, Yuko Takeishi, Yukiko Matsuzaka, Chika ohsawa. Effect of Surgery on Breast Cancer-Specific Mortality in Elderly Patients with Hormone Receptor-Positive, HER2-Negative Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-03-02.

Abstract RF02-04: A phase III study comparing trastuzumab emtansine with trastuzumab, pertuzumab, and docetaxel in older patients with metastatic HER2-positive breast cancer. (JCOG1607 HERB TEA study)

Abstract Background A combination of trastuzumab, pertuzumab, and docetaxel (HPD) is recommended as first-line treatment for patients with HER2-positive metastatic breast cancer. For older patients, it is difficult to maintain a relative dose intensity, which often impairs their quality of life. A new standard treatment option for older patients is required with less toxicity and non-inferior efficacy compared to HPD. Methods The eligibility criteria were as follows: age 65 years and older, HER2-positive metastatic breast cancer, no previous systemic treatment with chemotherapy and anti-HER2 targeted drugs, ECOG PS 0–2 for 65–74 years or 0–1 for 75 years or older, and adequate organ function. Treatment consisted of trastuzumab emtansine (T-DM1) 3.6 mg/kg every 3 weeks or HPD (trastuzumab 8 mg/kg, then 6 mg/kg, pertuzumab 840 mg, then 420 mg/body, and docetaxel 60 mg/m2, could be escalated to 75 mg/m2 if there were no unmanageable toxicity) every 3 weeks after a 1:1 ratio randomization. The trial was designed to achieve 70% power to confirm the non-inferiority of T-DM1 to HPD at a one-sided alpha of 5% with a non-inferiority margin of 1.35 in terms of the hazard ratio (HR) for overall survival (OS) as the primary endpoint. With a median OS of 30 months in both arms, 6.5 years of accrual, and 5 years of follow-up, the planned sample size was 250. Secondary endpoints were progression-free survival (PFS), response rate (RR), adverse events, cumulative breast cancer-specific mortality (BCSM), safety, and deterioration of activities of daily living. (Clinical Trial Information: UMIN000030783). Results In total, 148 patients were enrolled between January 2018 and March 2023. A total of 135 patients were assessed in the preplanned first interim analysis. The median patient age was 72 years (range 65-88) in the T-DM1 arm and 71 (65-84) in the HPD arm. The proportion of estrogen receptor-positive (10%) patients was well balanced between both arms (49.3 and 55.6%, respectively). Of these patients, 64.8% had stage IV disease and 35.2% had recurrent disease. T-DM1 was not non-inferior to HPD (HR 1.487; 99.9% CI, 0.288 to 7.678) in terms of OS. The median PFS was 9.8 months in the T-DM1 arm and 18.4 months in the HPD arm (HR 1.749; 95%CI, 1.124-2.723). Response rates were lower in the T-DM1 arm than that of the HPD arm (52.7% [95% CI, 38.8-66.4] and 76.8% [95% CI, 63.6-87.0], respectively) (p=0.099). BCSM was higher in the T-DM1 arm than that of the HPD arm (HR 1.617; 95% CI, 0.764-3.425). Grade 3 and higher neutropenia were less common in the T-DM1 arm than in the HPD arm (0 vs. 30.4%); however, thrombocytopenia was more common in the T-DM1 arm than in the HPD arm (16.9 vs. 0%). Grade 3 or more non-hematological adverse events were less common and lower in the T-DM1 arm (35.2%) than in the HPD arm (58.6%), including fatigue (5.6% vs. 22.9%), diarrhea (0% vs. 11.4%), appetite loss (8.5% vs. 11.4%), and febrile neutropenia (0% vs. 10.0%), which reduced the quality of life in older patients with HER2-positive metastatic breast cancer. Conclusion T-DM1 was not non-inferior to HPD in terms of OS. However, T-DM1 showed better tolerability in terms of frequency and severity of adverse events. HPD will continue to be the standard of care as the first-line treatment for older patients with HER2-positive metastatic breast cancer. Older patients with breast cancer have heterogeneous health conditions. A subset analysis according to age or geriatric assessment may identify the subpopulation of older patients with HER2-positive metastatic breast cancer for whom T-DM1 is an optional treatment. Citation Format: Akihiko Shimomura, Kenji Tamura, Keita Sasaki, Ryo Sadate, Akihiko Suto, Masataka Sawaki, Naohito Yamamoto, Tomoyuki Yoshiyama, Takako Hayashi, Eriko Tokunaga, Takashi Yamanaka, Chikako Shimizu, Tadahiko Shien, Hiroji Iwata. A phase III study comparing trastuzumab emtansine with trastuzumab, pertuzumab, and docetaxel in older patients with metastatic HER2-positive breast cancer. (JCOG1607 HERB TEA study) [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr RF02-04.

Abstract PS13-08: Chemotherapy in geriatric patients with early stage HER2+ breast cancer: A National Cancer Database analysis

Abstract Background Breast cancer (BC) incidence increases with age and women ≥ 65 years account for almost half of BC related mortality. Life expectancy has increased in the US due to improvements in medical care, and therefore the number of older patients with a BC diagnosis is also expected to increase. The population of individuals ≥ 80 years in the US is growing and now comprises more than 9 million. Approximately 15% of BC are human epidermal growth factor receptor 2 amplified (HER2+). The combination of chemotherapy with trastuzumab +/- pertuzumab compared with trastuzumab alone has been shown to be cost-effective in patients 70 years and older but trastuzumab monotherapy could be considered as an option in certain patients. Nevertheless, there is limited guidelines on how to properly care for the geriatric population with HER2+ BC. Methods We conducted a retrospective analysis of data collected from the National Cancer Database (NCDB). NCDB is a joint project of the Commission on Cancer of the American College of Surgeons and the American Cancer Society. Women ≥65 years with stage I, II and III HER2+ BC were included in the analysis. Patients were categorized into three treatment groups – those who did not receive chemotherapy or monoclonal antibodies (no-CT/mAbs), those who received chemotherapy in combination with monoclonal antibodies (CT/mAbs) and those who received monoclonal antibodies alone (mAbs). Using the Logrank P value, we explored the age cut off for which survival rates were not significantly different between treatment groups. Two comparisons were done: no-CT/mAbs vs CT/mAbs and CT/mAbs vs mAbs. The main outcome of this study was all-cause mortality. RESULTS: For the first comparison, a total of 9,924 HER2+ early-stage BC patients were included. Of these, 3,052 (30.8%) received no-CT/mAbs, while 6,872 (69.2%) received CT/mAbs. Kaplan Meier curves comparing mortality by treatment in the whole sample showed that those in the CT/mAbs group had significantly improved survival, compared to the no-CT/mAbs group (Logrank P &amp;lt; 0.001). The 1-year and 3-year survival rates were significantly higher in the CT/mAbs, compared to no-CT/mAbs. Cox proportional regression analysis showed that in the whole sample all-cause mortality was significantly lower among patients in the CT/mAbs group, compared to those in the no-CT/mAbs group (hazard ratio [HR], 0.48; CI: 0.41-0.57). However, the Logrank P values showed that there was no age cut off over which CT/mAbs did not improve survival compared to No-CT/mAbs. For the second comparison, a total of 7,457 patients were included. Of these 6,872 (92.2%) receive CT/mAbs and 585 (7.8%) received mAbs. The 1-year and 3-year survival rates were significantly higher in the CT/mAbs compared to the mAbs. The Logrank P values showed that there was no age cut off over which CT/mAbs did not improve survival compared to mAbs. Conclusion Chemotherapy in combination with HER2 directed monoclonal antibodies showed a survival benefit in elderly patients, irrespective of age, when compared to no-CT/mAb and mAb alone. These data highlight the importance of individualizing treatment recommendations and not forgoing standard therapy based merely on age. Limitations of the analysis include lack of available information on BC specific mortality. Also, the benefit that we identified could be secondary to selection bias. Additional studies are needed to improve the treatment in elderly patients with HER2+ BC. Table 1. Logrank P values for survival comparison between those who received CT/mAbs and No-CT/mAbs by age cut-off. Citation Format: Ana Sandoval-Leon, Yolcar Chamorro, Muni Rubens, Mukesh Roy, Lauren Carcas, Naomi Dempsey, Manmeet Ahluwalia, Reshma Mahtani. Chemotherapy in geriatric patients with early stage HER2+ breast cancer: A National Cancer Database analysis [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS13-08.