Estrogen Receptor-positive Early Breast Cancer Research Articles

Advances in Treatment for Oestrogen Receptor-Positive Breast Cancer

THIS YEAR the European Society for Medical Oncology (ESMO) Congress was hosted in Barcelona, Spain from 13th–17th September. Among the many impactful sessions, a symposium titled ‘Incorporating Novel Treatment Insights for Estrogen Receptor-Positive (ER+) Early Breast Cancer Patients’ garnered particular attention. Featuring presentations by Stephen Johnston, Royal Marsden, London, UK; Nadia Harbeck, Ludwig Maximilian University of Munich, Germany; and Etienne Brain, Institut Curie in Paris & Saint-Cloud, France, the session provided a comprehensive overview of current advances in ER+ early breast cancer treatment. The speakers explored adjuvant endocrine therapies, prognostic and predictive factors for clinical decision-making, and the unique challenges of optimising treatment for older patients, underscoring the evolving landscape of personalised care in ER+ early breast cancer.

Reductions in recurrence in women with early breast cancer entering clinical trials between 1990 and 2009: a pooled analysis of 155 746 women in 151 trials

Distant recurrence in women with oestrogen receptor-positive early breast cancer persists at a constant rate for more than 20 years after diagnosis, with little equivalent data for oestrogen receptor-negative breast cancer. Using the database of the Early Breast Cancer Trialists' Collaborative Group (EBCTCG) we investigated rates of distant breast-cancer recurrence in oestrogen receptor-positive and oestrogen receptor-negative tumours and trends in outcomes over time. In this pooled analysis of randomised controlled trial data, patients in the EBCTCG database of more than 650 000 women in trials of treatment for early-stage breast cancer were screened for eligibility. Women were eligible if they were enrolled between 1990 and 2009 and newly diagnosed with oestrogen receptor-positive breast cancer and scheduled for at least 5 years of endocrine therapy, or oestrogen receptor-negative disease, and if they were younger than 75 years at diagnosis, had a tumour diameter of 50 mm or less, and fewer than ten positive axillary lymph nodes, and no evidence of distant metastases at entry. Trial of neoadjuvant therapy, or those in which adjuvant therapy was unclear, and women with oestrogen receptor-negative, progesterone receptor-positive disease, or those for whom outcome or baseline data were missing were excluded. The primary outcome was time to first distant recurrence as defined by each trial, ignoring any locoregional recurrence or contralateral breast cancer. 10-year risks of distant recurrence by period of diagnosis were compared using Cox regression adjusted for patient and tumour characteristics, trial, and assigned treatment. Of the 652 258 women with early breast cancer in the EBCTCG database on Jan 17, 2023, patient-level data were available from 151 randomised trials that included 155 746 women. Rates of distant tumour recurrence improved similarly in women with oestrogen receptor-positive and oestrogen receptor-negative tumours. 80·5% of the improvement for oestrogen receptor-positive disease and 89·8% of the improvement for eostrogen receptor-negative disease was explained by changes in patient and tumour characteristics and improved treatments, but remained significant (p<0·0001). More recently diagnosed patients were more likely to have node-negative disease. 10-year distant recurrence risks during 1990-99 versus 2000-09 were as follows: for node-negative disease, 10·1% versus 7·3% for oestrogen receptor-positive disease and 18·3% versus 11·9% for oestrogen receptor-negative disease; for disease with one to three positive nodes, 19·9% versus 14·7% for oestrogen receptor-positive disease and 31·9% versus 22·1% for oestrogen receptor-negative disease; and for disease with four to nine positive nodes, 39·6% versus 28·5% for oestrogen receptor-positive disease and 47·8% versus 36·5% for oestrogen receptor-negative disease. After adjustment for therapy, rates were reduced by 25% (oestrogen receptor-positive disease) and 19% (oestrogen receptor-negative disease) after 2000 versus the 1990s, with similar improvements observed in oestrogen receptor-positive disease beyond 5 years. Most of the improvement in trial outcomes is explained by a greater proportion of women with lower-risk disease entering trials and improved adjuvant treatment. After adjustment, women diagnosed since 2000 have about a fifth lower rate of distant recurrence than the 1990s. Long-term risks of distant recurrence for oestrogen receptor-positive disease remain, but are about a tenth lower now than in our previous report. Cancer Research UK, UK Medical Research Council.

285P Adherence to endocrine therapy and sexual dysfunction in patients older than 65 years with early estrogen receptor-positive breast cancer

285P Adherence to endocrine therapy and sexual dysfunction in patients older than 65 years with early estrogen receptor-positive breast cancer

The cardiovascular and metabolic effects of ovarian suppression in combination with tamoxifen or an aromatase inhibitor as adjuvant therapy for early estrogen receptor-positive breast cancer: a systematic review

Adjuvant endocrine therapy is a key treatment in oestrogen receptor positive early breast cancer (BC). For premenopausal women ovarian function suppression (OFS) in combination either tamoxifen or aromatase inhibitor (AI) is utilised in high-risk cases. The resultant suppression of circulating oestradiol from OFS could have adverse cardiovascular and metabolic effects, subsequently increasing the risk of cardiovascular disease. Our study highlights the potential cardio-metabolic impact endocrine therapy and OFS have on premenopausal women with BC. It also highlights the pressing need for standardisation of routine collection and recording of cardiometabolic history and risk factors as part of baseline assessment and adverse event reporting to better understand the cardiometabolic impact these treatment has on our patients. Further studies, with particular focus on baseline and subsequent development of cardiovascular risk factors are needed to explore the impact of these drugs on the cardiovascular health of these young women with BC

Epidemiology of early vs late recurrence among women with early stage estrogen receptor-positive breast cancer in the Pathways Study.

Relatively little is known about the differences in prognostic factors for early vs late recurrence among women with early stage estrogen receptor-positive breast cancer. We analyzed factors related to early (<5 years) vs late (≥5 years) recurrence in 2992 women with stage I-IIB estrogen receptor-positive breast cancer in the Pathways Study, a prospective cohort of women with breast cancer enrolled between 2006 and 2013, with ascertainment of recurrence and death through December 2021. After a median follow-up of 13.3 years, 341 (13.8%) women had recurrences, including 181 (53.7%) with late recurrence. Higher stage and grade were associated with recurrence regardless of timing, whereas progesterone receptor negativity was associated with early but not late recurrence. Receipt of endocrine therapy was associated with reduced risk of overall recurrence, but the length of endocrine therapy was not statistically significant in multivariable models. Minoritized racial and ethnic groups, including Asian, Black, and Hispanic women, had higher risk of early but not late recurrence compared to non-Hispanic White women. The trend of higher risk of early recurrence among these groups remained after adjustment for clinical, demographic, and socioeconomic factors but was statistically significant only in Asian women. Our study revealed potentially important distinctions for early vs late recurrence, including the associations with progesterone receptor negativity and self-identified race and ethnicity. Possible higher risk of early recurrence among Asian, Black, and Hispanic women provides novel evidence for the existence of disparities in cancer outcomes, even within the breast cancer subtype indicative of generally good prognosis.

A prospective study on tumour response assessment methods after neoadjuvant endocrine therapy in early oestrogen receptor-positive breast cancer

BackgroundNeoadjuvant endocrine therapy (NET) in oestrogen receptor-positive (ER+) /HER2-negative (HER2-) breast cancer allows real-time evaluation of drug efficacy as well as investigation of the biological and molecular changes that occur after estrogenic deprivation. Clinical and pathological evaluation after NET may be used to obtain prognostic and predictive information of tumour response to decide adjuvant treatment. In this setting, clinical scales developed to evaluate response after neoadjuvant chemotherapy are not useful and there are not validated biomarkers to assess response to NET beyond Ki67 levels and preoperative endocrine prognostic index score (mPEPI).MethodsIn this prospective study, we extensively analysed radiological (by ultrasound scan (USS) and magnetic resonance imaging (MRI)) and pathological tumour response of 104 postmenopausal patients with ER+ /HER2- resectable breast cancer, treated with NET for a mean of 7 months prior to surgery. We defined a new score, tumour cellularity size (TCS), calculated as the product of the residual tumour cellularity in the surgical specimen and the tumour pathological size.ResultsOur results show that radiological evaluation of response to NET by both USS and MRI underestimates pathological tumour size (path-TS). Tumour size [mean (range); mm] was: path-TS 20 (0–80); radiological-TS by USS 9 (0–31); by MRI: 12 (0–60). Nevertheless, they support the use of MRI over USS to clinically assess radiological tumour response (rad-TR) due to the statistically significant association of rad-TR by MRI, but not USS, with Ki67 decrease (p = 0.002 and p = 0.3, respectively) and mPEPI score (p = 0.002 and p = 0.6, respectively). In addition, we propose that TCS could become a new tool to standardize response assessment to NET given its simplicity, reproducibility and its good correlation with existing biomarkers (such as ΔKi67, p = 0.001) and potential added value.ConclusionOur findings shed light on the dynamics of tumour response to NET, challenge the paradigm of the ability of NET to decrease surgical volume and point to the utility of the TCS to quantify the scattered tumour response usually produced by endocrine therapy. In the future, these results should be validated in independent cohorts with associated survival data.

Circulating miRNA Expression Is Inversely Correlated with Tumor Tissue or Sentinel Lymph Nodes in Estrogen Receptor-Positive Early Breast Cancer Patients.

The deregulation of microRNAs (miRNAs) is associated with the various steps of the metastatic process. In addition, circulating miRNAs are remarkably stable in peripheral blood, making them ideal noninvasive biomarkers for disease diagnosis. Here, we performed a proof-of-principle study to determine whether tumor-tissue-derived miRNAs are traceable to plasma in ER-positive early breast cancer patients. We performed RNA-sequencing on 30 patients for whom plasma, sentinel lymph nodes (SLNs) and tumor tissue were available. We carried out differential expression, gene ontology and enrichment analyses. Our results show that circulating miRNAs are inversely expressed compared with tumor tissue or SLNs obtained from the same patients. Our differential expression analysis shows the overall downregulation of circulating miRNAs. However, the expression of miR-643a-3p and miR-223 was up-regulated in patients with positive SLNs. Furthermore, gene ontology analysis showed the significant enrichment of biological processes associated with the regulation of epithelial cell proliferation and transcriptional regulation commonly involved in the promotion of metastases. Our results suggest the potential role of several circulating miRNAs as surrogate markers of lymph node metastases in early breast cancer patients. Further preclinical and clinical studies are required to understand the biological significance of the most significant miRNAs and to validate our results in a larger cohort of patients.

A nomogram based on cuproptosis-related genes predicts 7-year relapse-free survival in patients with estrogen receptor-positive early breast cancer.

Excess copper induces cell death by binding to lipoylated components of the tricarboxylic acid cycle. Although a few studies have examined the relationship between cuproptosis-related genes (CRGs) and breast cancer prognosis, reports on estrogen receptor-positive (ER+) breast cancer are lacking. Herein, we aimed to analyze the relationship between CRGs and outcomes in patients with ER+ early breast cancer (EBC). We conducted a case-control study among patients with ER+ EBC presenting poor and favorable invasive disease-free survival (iDFS) at West China Hospital. Logistic regression analysis was performed to establish the association between CRG expression and iDFS. A cohort study was performed using pooled data from three publicly available microarray datasets in the Gene Expression Omnibus database. Subsequently, we constructed a CRG score model and a nomogram to predict relapse-free survival (RFS). Finally, the prediction performance of the two models was verified using training and validation sets. In this case-control study, high expression of LIAS, LIPT1, and ATP7B and low CDKN2A expression were associated with favorable iDFS. In the cohort study, high expression of FDX1, LIAS, LIPT1, DLD, PDHB, and ATP7B and low CDKN2A expression were associated with favorable RFS. Using LASSO-Cox analysis, a CRG score was developed using the seven identified CRGs. Patients in the low CRG score group had a reduced risk of relapse in both training and validation sets. The nomogram included the CRG score, lymph node status, and age. The area under the receiver operating characteristic (ROC) curve (AUC) of the nomogram was significantly higher than the AUC of the CRG score at 7 years. The CRG score, combined with other clinical features, could afford a practical long-term outcome predictor in patients with ER+ EBC.

35P SNPs of aromatase gene (CYP19A1) and outcomes of patients with estrogen receptor-positive (ER+) early breast cancer (eBC) treated with aromatase inhibitors (AIs): A multicenter, prospective study

35P SNPs of aromatase gene (CYP19A1) and outcomes of patients with estrogen receptor-positive (ER+) early breast cancer (eBC) treated with aromatase inhibitors (AIs): A multicenter, prospective study

Phase III study of long-term prognosis of estrogen receptor-positive early breast cancer treated with neoadjuvant endocrine therapy with/without adjuvant chemotherapy

PurposeNeoadjuvant endocrine therapy (NET) is a treatment option for estrogen receptor-positive (ER+) postmenopausal early breast cancer (EBC). This phase III trial evaluated the prognosis of EBC patients treated with/without chemotherapy (CT) following NET.MethodsER+/HER2−, T1c-2, and clinically node-negative EBC patients were enrolled in 2008–2013 and treated with endocrine therapy (ET) in weeks 24–28. All patients, excluding those with progressive disease (PD) during NET or ≥ 4 positive lymph nodes after surgery, were randomized to ET for 4.5–5 years with/without CT. The primary endpoint was disease-free survival (DFS). Secondary endpoints included distant DFS (DDFS), overall survival (OS), and DFS/DDFS/OS according to clinical response to NET.ResultsOf 904 patients, 669 were randomized to CT+ET (n = 333) or ET alone (n = 336). The median follow-up was 7.8 years. DFS (CT+ET, 47 events; ET alone, 70 events) and DDFS did not reach the planned numbers of events. Eight-year DFS/DDFS rates were 86%/93% and 83%/92%, respectively. DFS was significantly better in CT+ET than ET alone in subgroups aged < 60 years (P = 0.016), T2 (P = 0.013), or Ki67 > 20% (P = 0.026). Progesterone receptor and histological grade were predictive markers for clinical responses to NET.ConclusionNET may be used as standard treatment for patients with ER+EBC. Although it is difficult to decide whether to administer adjuvant CT based solely on the effect of NET, the response to NET may help to inform this decision.Trial registrationThis study was registered at the UMIN Clinical Trials Registry under UMIN000001090 (registered 20 March 2008).

A Real-World Data Retrospective Cohort Study of Low Estrogen Receptor-Positive Early Breast Cancer: Natural History and Treatment Outcomes.

PurposeEstrogen receptor-positive (ER+) breast cancer (BC) is a heterogeneous disease, and there is an ongoing debate regarding the optimal cut point for clinically relevant ER expression. We used a real-world database to assess the prognostic and predictive values of lower ER expression levels on treatment outcomes with endocrine therapy.MethodsWe used a nationwide electronic health record database. Descriptive statistics were used to evaluate the association between ER expression, tumor characteristics, and treatment patterns among patients with early-stage BC. We used Kaplan–Meier survival curves to estimate recurrence-free survival (RFS) and overall survival (OS). We assessed associations between an alternative ER expression-level cut point and clinical outcomes.ResultsAmong 4697 patients with early-stage HER2-negative BC, 83 (2.04%) had ER+-low BC (ER expression, 1–9.99%) and 36 (0.88%) had ER+-intermediate BC (10–19.9%). ER+-low tumors were associated with higher tumor grade, larger size, and higher axillary tumor burden than ER+-high tumors (≥20% ER expression). African Americans had a higher prevalence of both triple-negative BC (TNBC) and ER+-low BC than ER+-high BC. Patients with ER+-low and ER+-intermediate tumors had survival outcomes similar to patients with TNBC and worse survival outcomes than patients with ER+-high tumors (P < 0.001). Tumors with <20% ER expression were associated with worse outcomes.ConclusionIn our cohort, patients with BCs with ER expression levels <20% had poor clinical outcomes similar to those of patients with TNBC.

Cyclin-dependent kinase 4 and 6 inhibitors in combination with neoadjuvant endocrine therapy in estrogen receptor-positive early breast cancer: a systematic review and meta-analysis.

The combination of cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors and endocrine treatment has benefited patients with estrogen receptor-positive/human epidermal growth factor receptor 2-negative (ER + /HER2-) metastatic breast cancer; however, its effects in the neoadjuvant setting for ER + /HER2- early breast cancer (EBC) are unclear. Systematic searches were performed in PubMed, Embase, Cochrane Library, and major oncological meetings for trials of CDK4/6 inhibitors plus neoadjuvant endocrine treatment (NET) vs. NET/neoadjuvant chemotherapy (NACT) alone up to January 30, 2021. We assessed the efficacy of CDK4/6 inhibitors plus NET vs. NET/NACT alone in ER + /HER2- EBC. Six studies that included 803 patients treated with CDK4/6 inhibitors plus NET vs. NET/NACT alone were used. Compared with NET/NACT alone, CDK4/6 inhibitors plus NET increased the complete cell cycle arrest (CCCA) rate (OR, 9.00; 95% CI, 5.42-14.96; P < 0.001). Nonsignificant differences between CDK4/6 inhibitors and NET/NACT alone occurred in the preoperative endocrine prognostic index (PEPI)-0 rate (OR, 1.13; 95% CI, 0.59-2.18; P = 0.71), pathological complete response (pCR) rate (OR, 0.75; 95% CI, 0.13-4.29; P = 0.74), objective response rate (ORR) (OR, 0.70; 95% CI, 0.21-2.29; P = 0.55), and disease control rate (DCR) (OR, 1.16; 95% CI, 0.47-2.89; P = 0.74). CDK4/6 inhibitors plus NET indicated a high risk of neutropenia (OR, 56.43; 95% CI, 15.76-202.11; P < 0.001) as an adverse effect (AE) and elevated alanine aminotransferase (ALT) level (OR, 15.30; 95% CI, 2.02-115.98; P = 0.008) as grade 3/4 AEs. Compared with NET/NACT alone, CDK4/6 inhibitors plus NET increased CCCA rate in ER + /HER2- EBC patients. CDK4/6 inhibitors plus NET did not substantially improve the PEPI-0 rate, pCR rate, ORR, or DCR. The combination increased the risk of neutropenia and elevated ALT levels. In the neoadjuvant setting, addition of CDK4/6 inhibitors to NET may be an option for treating ER + /HER2- EBC.

Adjuvant tamoxifen switched to exemestane treatment in postmenopausal women with estrogen receptor-positive early breast cancer: A pragmatic, multicenter, and prospective clinical trial in China.

This post-approval safety study assessed the efficacy and safety of exemestane after 2-3 years of tamoxifen treatment among postmenopausal women with estrogen receptor-positive (ER+) early breast cancer in China. Enrolled patients had received 2-3 years of tamoxifen and were then switched to exemestane for completion of 5 consecutive years of adjuvant endocrine therapy. The primary endpoint was the time from enrollment to the first occurrence of locoregional/distant recurrence of the primary breast cancer, appearance of a second primary or contralateral breast cancer, or death due to any cause. Other endpoints included the proportion of patients experiencing each event, incidence rate per annum, relationships between human epidermal growth factor receptor 2 status and time to event, and relationship between disease history variables and time to event. Overall, 558 patients were included in the full analysis set: 397 (71.1%) completed the study, 20 experienced an event, and 141 discontinued [47 owing to an adverse event (AE); 37 no longer willing to participate]. Median duration of treatment was 29.5 (range, 0.1-57.7) months. Median time to event was not reached. Event-free survival probability at 36 months was 91.4% (95% CI, 87.7%-95.1%). The event incidence over the total exposure time of exemestane therapy was 3.5 events/100 person-years (20/565). Multivariate analysis showed an association between tumor, lymph node, and metastasis stage at initial diagnosis and time to event [hazard ratio: 1.532 (95% CI, 1.129-2.080); P=0.006]. Most AEs were grade 1 or 2 in severity, with arthralgia (7.7%) being the most common treatment-related AE. This study supports the efficacy and safety of exemestane in postmenopausal Chinese women with ER+ breast cancer previously treated with adjuvant tamoxifen for 2-3 years. No new safety signals were identified in the Chinese population.

Impact of the EndoPredict genomic assay on treatment decisions for oestrogen receptor-positive early breast cancer patients: benefits of physician selective testing.

Genomic tests improve accuracy of risk prediction for early breast cancers but these are expensive. This study evaluated the clinical utility of EndoPredict®, in terms of impact on adjuvant therapy recommendations and identification of parameters to guide selective application. Patients with ER-positive, HER2-negative, and early-stage invasive breast cancer were tested with EndoPredict®. Two cohorts were recruited: one consecutively and another at clinical team discretion. Systemic treatment recommendations were recorded before and after EndoPredict® results were revealed to the multidisciplinary team. 233 patients were recruited across five sites: 123 consecutive and 110 at clinical team discretion. In the consecutive cohort 50.6% (62/123) cases were classified high risk of recurrence by EndoPredict®, compared with 62.7% (69/110) in the selective cohort. A change in treatment recommendation was significantly more likely (p < 0.0001) in the selective cohort (43/110, 39.1%) compared to the consecutive group (11/123, 8.9%). The strongest driver of selective recruitment was intermediate grade histology, whilst logistic regression modelling demonstrated that nodal status (p < 0.001), proliferative rate (p = 0.001), and progesterone receptor positivity (p < 0.001) were the strongest discriminators of risk. Whilst molecular risk can be predicted by traditional variables in a high proportion of cases, EndoPredict® had a greater impact on treatment decisions in those cases selected for testing at team discretion. This is indicative of the robust ability of the clinical team to identify cases most likely to benefit from testing, underscoring the value of genomic tests in the oncologists' tool kit.

Preliminary Pharmacogenomic-Based Predictive Models of Tamoxifen Response in Hormone-dependent Chilean Breast Cancer Patients.

Tamoxifen (TAM), a selective oestrogen receptor modulator, is one of the most used treatments in oestrogen receptor-positive (ER+) early and metastatic breast cancer (BC) patients. The response to TAM has a high degree of inter-individual variability. This is mainly due to genetic variants in CYP2D6 gene, as well as other genes encoding proteins involved in the TAM pharmacokinetic and/or pharmacodynamic. Therefore, prediction of the TAM response using these genetic factors together with other non-genetic variables may be relevant to improve breast cancer treatment. Thus, in this work, we used genetic polymorphisms and clinical variables for TAM response modelling. One hundred sixty-two ER + BC patients with 2 years of TAM treatment were retrospectively recruited, and the genetic polymorphisms CYP2D6*4, CYP3A4*1B (CYP3A4*1.001), CYP3A5*3, UGT2B7*2, UGT2B15*2, SULT1A1*2, and ESRA V364E were analyzed by PCR-RFLP. Concomitantly, the therapeutic response was obtained from clinical records for association with genotypes using univariate and multivariate biostatistical models. Our results show that UGT2B15*1/*2 genotype protects against relapse (OR = 0.09; p = 0.02), CYP3A5*3/*3 genotype avoids endometrial hyperplasia (OR = 0.07; p = 0.01), SULT1A1*1/*2 genotype avoids vaginal bleeding (OR = 0.09; p = 0.03) and ESRA 364E/364E genotype increases the probability of vaginal bleeding (OR = 5.68; p = 0.02). Logistic regression models, including genomic and non-genomic variables, allowed us to obtain preliminary predictive models to explain relapse (p = 0.010), endometrial hyperplasia (p = 0.002) and vaginal bleeding (p = 0.014). Our results suggest that the response to TAM treatment in ER + BC patients might be associated with the presence of the studied genetic variants in UGT2B15, CYP3A5, SULT1A1 and ESRA genes. After clinical validation protocols, these models might be used to help to predict a percentage of BC relapse and adverse reactions, improving the individual response to TAM-based treatment.

A review of endocrine therapy in early estrogen receptor-positive breast cancer by St. Gallen Breast Cancer Conference 2021

A review of endocrine therapy in early estrogen receptor-positive breast cancer by St. Gallen Breast Cancer Conference 2021

Lymphovascular invasion, race, and the 21-gene recurrence score in early estrogen receptor-positive breast cancer

Lymphovascular invasion (LVI) and Black race are associated with poorer prognosis in early breast cancer (EBC). We evaluated the association between LVI and race, and whether LVI adds prognostic benefit to the 21-gene recurrence score (RS) in EBC. Women with ER+ HER2− EBC measuring up to 5 cm, with 0–3 involved axillary nodes, diagnosed between 1 January 2010 and 1 January 2014, who underwent surgery as first treatment and had available RS, were identified in the NCDB database. Bivariate associations between two categorical variables were examined using chi-square test. Multivariate Cox proportional hazards model were used to assess the association of LVI, race, and other covariates with overall survival (OS). 77,425 women, 65,018 node-negative (N0), and 12,407 with 1–3 positive (N+) nodes, were included. LVI was present in 12.7%, and associated with poor grade, RS 26–100, and N+ (all p < 0.0001), but not Black race. In multivariate analysis, LVI was associated with worse OS in N0 [HR 1.37 (95% CI 1.27, 1.57], but not N+ EBC. LVI was associated with worse OS in N0 patients with RS 11–25 [HR 1.31 (95% CI 1.09, 1.57)] and ≥26 [HR 1.58 (95% CI 1.30, 1.93)], but not RS 0–10. No interaction between LVI and chemotherapy benefit was seen. Black race was associated with worse OS in N0 (HR 1.21, p = 0.009) and N+ (HR 1.37, p = 0.015) disease. LVI adds prognostic information in ER+, HER2−, N0 BCA with RS 11–100, but does not predict chemotherapy benefit. Black race is associated with worse OS, but not LVI.

Clinical validity of clinical treatment score 5 (CTS5) for estimating risk of late recurrence in unselected, non-trial patients with early oestrogen receptor-positive breast cancer

PurposeClinical Treatment Score at 5 years (CTS5) is a prognostic tool to estimate distant recurrence (DR) risk after 5 years of endocrine therapy for postmenopausal women with oestrogen receptor-positive (ER-positive) breast cancer.MethodsThe validity of CTS5 was tested in a retrospective cohort of patients diagnosed with early ER-positive breast cancer. The primary endpoint was DR in years 5–10. The primary analysis cohort consisted of postmenopausal women, with premenopausal women as a secondary analysis cohort. Cox regression models were used to determine the prognostic value of CTS5 and Kaplan–Meier curves were used with associated 10-year DR risks (%).Results2428 women were included with a median follow-up of 13.4 years. The CTS5 was significantly prognostic in both postmenopausal (N = 1662, HR = 2.18 95% CI (1.78–2.67)) and premenopausal women (N = 766, HR = 1.84 95% CI (1.32–2.56)). The 10-year DR risks were 2.9% (1.9–4.5), 7.2% (5.3–9.9), and 12.9% (10.0–16.7) for low, intermediate and high risk in postmenopausal women and 3.8% (2.2–6.7), 6.9% (4.4–10.8), and 11.1% (7.4–16.5) in premenopausal women, respectively. The number of observed DRs was significantly greater than expected in those predicted to be at high risk by CTS5 but this discordance was lost when those receiving more than 60 months of endocrine therapy were excluded.ConclusionsThe CTS5 demonstrated clinical validity for predicting late DR within a large cohort of unselected postmenopausal patients but less so in premenopausal patients. Calibration of the CTS5 was good in patients who did not receive extended endocrine therapy. The CTS5 low-risk cohort has risk of DR so low as to not warrant extended endocrine therapy.

Response to neoadjuvant chemotherapy and the 21-gene Breast Recurrence Score test in young women with estrogen receptor-positive early breast cancer.

The 21-gene Breast Recurrence Score test predicts benefit from adjuvant chemotherapy in estrogen receptor-positive, HER2-negative (ER+/HER2-) breast cancer (BC). We examined whether the 21-gene assay predicts response to neoadjuvant chemotherapy (NCT). We identified patients with stage I-III ER+/HER2- BC treated with NCT from the Young Women's Breast Cancer Study, a prospective cohort of women diagnosed with BC at age ≤40 years. The 21-gene assay was performed on tumor specimens removed prior to NCT either as part of clinical care or retrospectively for research. Pathological complete response (pCR) was defined as ypT0/is ypN0. The relationship between Recurrence Score result and pCR was evaluated using logistic regression modeling. 76 women received NCT for ER+/HER2- BC and were eligible for this analysis. Median age at diagnosis was 37 years (range 24-40). Scores ranged between 5 and 77 with 50% >25 and 5% <11. Median Recurrence Score result was significantly higher among tumors achieving pCR vs. non-pCR response (61.5 vs. 23, pwilcoxon = 0.0005). pCR rate in patients with scores >25 was 21% (8/38) vs. 5% in patients with scores <25 (2/38) (p = 0.09), with both pCRs in the <25 group in patients with scores between 21 and 25. In multivariable analysis, only Recurrence Score result was significantly associated with pCR (OR: 1.07, 95%CI 1.01-1.12, p = 0.01). In young women with ER+/HER2- BC who received NCT, higher pretreatment Recurrence Score result was associated with an increased likelihood of pCR. Gene expression profile assays may have a role in decision making in young women in need of neoadjuvant therapy.

HER2 positivity is not associated with adverse prognosis in high-risk estrogen receptor-positive early breast cancer patients treated with chemotherapy and trastuzumab

Co-expression of human epidermal growth factor receptor-2 (HER2) and hormone receptor (HR) predicted worse prognosis in early breast cancer before trastuzumab was developed. We aimed to investigate whether HER2 positivity was still associated with worse outcome in high-risk estrogen receptor (ER) positive patients treated with trastuzumab and chemotherapy. In the present study, 227 ER+/HER2+ patients treated with trastuzumab and chemotherapy (HER2-pos-T group) and 1097 ER+/HER2-patients treated with chemotherapy alone (HER2-neg group) during 2009 and 2015 were retrospectively enrolled for the comparison of disease-free survival (DFS) and overall survival (OS). At a median follow-up of 59 months, 174 DFS events and 69 deaths were observed. The estimated 5-year DFS rate was 94.2% in the HER2-pos-T group and 87.4% in the HER2-neg group (Log-rank P = 0.014). HER2-pos-T group was associated with significantly better DFS in multivariate analysis (HR 0.38, 95% CI: 0.22–0.67, Log-rank P = 0.001). The estimated 5-year OS rates for the two groups were 97.2% and 95.7%, respectively (Log-rank P = 0.183). In multivariable analysis, patients in the HER2-pos-T group had significantly better OS compared with those in the HER2-neg group (HR 0.40, 95% CI: 0.17–0.95, Log-rank P = 0.037). We concluded that high-risk ER+/HER2+ breast cancer patients treated with chemotherapy and trastuzumab had superior prognosis compared with ER+/HER2-patients. Therefore, HER2 positivity itself may not be considered as an unfavorable factor for ER + patients in the era of trastuzumab.