Quantitative Estrogen Receptor Research Articles

Abstract PO1-01-11: Development and Validation of a Breast Cancer Recurrence Model Demonstrates Accurate Identification of Patients with Favorable Long-Term Outcomes

Abstract Background: The Oncotype DX (ODX) test is a 21-gene expression assay widely used for the prediction of risk recurrence in early-stage breast cancer, but it may be possible to identify patients who can forgo testing using only clinicopathologic variables. In 2018, the National Cancer Database (NCDB) began reporting quantitative histologic parameters for estrogen receptor (ER), progesterone receptor (PR), and Ki-67 expression in breast cancer patients. Inclusion of these variables may improve the development of nationally applicable models to predict ODX results using clinicopathologic variables alone. Methods: Using a cohort of patients from the NCDB diagnosed from 2018–2020 with hormone receptor (HR)-positive, HER2-negative, Stage I-III breast cancer, we trained machine learning models to predict high-risk (26-100) ODX score. A subset comprising 80% of patients was used for model training, while the remaining data were set aside for internal validation. An external validation cohort was selected from the University of Chicago Medical Center (UCMC), including patients diagnosed from 2009–2021. Feature selection, model architecture selection, and hyperparameter tuning were performed using 10-fold cross-validation within the NCDB training set. We compared a model with quantitative ER, PR, and Ki-67; a model with only quantitative ER and PR, and a model without quantitative immunohistochemistry – to best reflect the likely data available in a variety of practice patterns. The primary endpoint was the area under the receiver operating characteristic curve (AUROC) for prediction of high-risk ODX results in the UCMC validation cohort. Models were also evaluated as rule-out tests to identify low-risk patients who did not require further ODX testing, using a high (90%) sensitivity threshold, fit in the NCDB training dataset. Results: We identified 53,346 patients from the NCDB cohort meeting the inclusion criteria; 7% had a high risk ODX score, with a median follow-up time of 28 months. The UCMC validation cohort included 896 patients, and was more diverse, with 30% non-Hispanic Black patients (versus 8% in NCDB), more high-risk patients (18% with high ODX), and a longer median follow-up time of 55 months. In the NCDB validation cohort, models incorporating quantitative ER/PR (AUROC 0.78, 95% CI 0.77–0.80) and quantitative ER/PR/Ki-67 (AUROC 0.81, 95% CI 0.80–0.83) both performed better than the non-quantitative model (AUROC 0.70, 95% CI 0.68–0.72). These results were preserved in the external UCMC cohort, where the ER/PR model (AUROC 0.86, 95% CI 0.80–0.92, p = 0.032) and the ER/PR/Ki-67 model (AUROC 0.87, 95% CI 0.81–0.93) outperformed the non-quantitative model (AUROC 0.80, 95% CI 0.73–0.87, p = 0.009). The high sensitivity rule-out threshold of the ER/PR model predicted that 30% of patients in the UCMC cohort would be low ODX, and the ER/PR/Ki-67 model predicted 44% as low risk – negative predictive value was over 96% for prediction of high ODX. Of the patients predicted to be low risk by the quantitative models, none had a documented high ODX score, and recurrence was < 3% at 5 years. The hazard ratio for recurrence free interval, adjusted for age and comorbidity score, of patients predicted to be high risk by this threshold was 2.96 (95% CI 1.02–8.58) for the ER/PR model and 3.84 (95% CI 1.48–9.97) for the ER/PR/Ki-67 model. Conclusions: We present externally validated and nationally applicable models that identify approximately half of HR-positive/HER2-negative breast cancer patients who are unlikely to have high ODX results using widely available quantitative clinicopathologic variables. Patients identified as low risk by these models have excellent long-term outcomes and may be able to forgo adjuvant chemotherapy without further genomic testing. Citation Format: Asim Dhungana, Augustin Vannier, Fangyuan Zhao, Jincong Freeman, Poornima Saha, Megan Sullivan, Katharine Yao, Elbio Flores, Olufunmilayo Olopade, Dezheng Huo, Alexander Pearson, Frederick Howard. Development and Validation of a Breast Cancer Recurrence Model Demonstrates Accurate Identification of Patients with Favorable Long-Term Outcomes [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 PO1-01-11.

Abstract P4-02-26: Quantitative estrogen receptor expression affects pathologic complete response to neoadjuvant chemotherapy in patients with early-stage breast cancer with low expression of HER2

Abstract BACKGROUND Recent pooled analysis of four major clinical trials of neoadjuvant chemotherapy (NAC) indicated that tumors with low expression of HER2 (HER2-low) as defined by immunohistochemistry (IHC) could be a new subgroup of breast cancer, distinct from HER2-negative tumors. In estrogen receptor (ER)-positive/HER2-negative breast cancer, we previously reported that 9.5% ER expression by IHC was the most appropriate cutoff to predict survival outcomes. However, little is known about the effect of quantitative ER expression on NAC outcomes in patients with HER2-low breast cancer. The present study aimed to elucidate the role of quantitative ER expression as a predictive and prognostic biomarker in the newly established HER2-low subgroup. MATERIALS AND METHODS We retrospectively reviewed the charts of 2,016 patients with newly diagnosed ER- and/or progesterone receptor (PR)-positive breast cancer between January 1982 and January 2019 in an extensive clinical database at The University of Texas MD Anderson Cancer Center. Our analysis included patients whose ER%, PR%, and HER2 IHC (0 to 2+) data were available. HER2-low was defined as IHC 1+ and 2+/situ hybridization (ISH)-negative. All patients had stage II or III disease at presentation and received NAC with anthracycline and a taxane-based combination regimen. Those with ER-positive tumors also received adjuvant endocrine therapy. The primary outcome measure was pathologic complete response (pCR) rate, compared between groups using logistic regression. Secondary outcomes were progression-free survival and overall survival after NAC completion, compared using Kaplan-Meier analysis and the log-rank test. The cutoff value for ER and PR positivity was 10% in the main analysis, identified by recursive partitioning and regression trees. RESULTS Among the 2,016 patients, 1134 (56%) had cStage II and 882 (44%) had cStage III disease. For IHC HER2 levels, 739 patients had 0 (37%), 926 had 1+ (46%), and 351 had 2+ (17%). For the primary outcome, 123 patients (6%) achieved pCR. The median follow-up period was 6.78 years. During the follow-up, 571 (28%) had distant metastasis. Mean ER expression (%) increased with HER2 IHC (HER2 IHC 0: 74.2%, 1+: 76.7%, 2+: 78.2%). In the multivariate logistic model, ER-negative (p< 0.0001), PR-negative (p < 0.0001), and high nuclear grade (p< 0.05) disease were associated with higher pCR rates. Although pCR rate did not differ among HER2 IHC groups (0 = 6.09%, 1+ = 6.26%, 2+ = 5.7%; p=0.93), significantly higher pCR rates were observed in the HER2 IHC=0/1+ and 1%≤ER< 10% group (p=0.0013) than in the HER2 IHC=0/1+ and ER≥10%, and HER2 IHC=2+ and ER≥10% groups. Kaplan-Meier curves showed that patients in the ER≥10% group had marginally improved PFS (p=0.046) and significantly longer OS (p=0.004) regardless of HER2 IHC status. Multivariable analysis showed that HER IHC status did not affect survival outcomes. Exploratory analysis showed that the patients with 70% or less in ER expression and HER2 IHC 1+/2+ tumor had higher pCR rate (12.3%) compared to those with ER>70% (4.1%). CONCLUSIONS Patients with ≥10% ER expression had better survival outcomes than those with ER< 10% regardless of HER2 expression level. The degree of HER2 expression in the HER2-low subgroup was not an independent predictive and prognostic factor for NAC response. The cutoff for ER expression for its predictive effect on pCR needs further validation in large external datasets. Citation Format: Toshiaki Iwase, Takeo Fujii, Clinton Yam, Wenli Dong, Yu Shen, Debu Tripathy, Naoto T. Ueno. Quantitative estrogen receptor expression affects pathologic complete response to neoadjuvant chemotherapy in patients with early-stage breast cancer with low expression of HER2 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-02-26.

The Quantitative ER Immunohistochemical Analysis in Breast Cancer: Detecting the 3 + 0, 4 + 0, and 5 + 0 Allred Score Cases.

Background and objectives: The currently used immunohistochemical approach in determining the estrogen receptor (ER) positivity of breast cancers (BCs) is inherently subjective and additionally limited by its semi-quantitative nature. The application of software in the analysis of digitized slide images may overcome some of these limitations. However, the utilization of such an approach requires that the entire staining procedure is standardized. Background and objectives: We aimed to establish a procedure for the photometric and morphometric analysis of BC immunohistochemical parameters that can possibly be used for a diagnostic purpose that is in line with the current semi-quantitative scoring system. Materials and Methods: Semi-quantitative analysis of ER-stained tissue sections was performed following the Allred scoring system guidelines. The quantitative analysis was performed in ImageJ software after color deconvolution. The quantitative analysis of 66 cases of invasive lobular BC included: Percent of ER-positive cells, average nuclear coloration intensity, and the quantitative ER score. The percent of ER-positive tumor cells was counted using a standard grid overlay, while optical density (0.0–1.0) was measured within each nucleus at the grid points. Results: A statistical analysis revealed a significant positive correlation (r = 0.886, p < 0.001) between the subjective semi-quantitative and quantitative ER scores, with a large effect size (d = 3.8215). We observed strong statistically significant correlations between individual parameters of the total ER score, percentage of ER-positive nuclei, and color intensity, obtained by the two independent methods. Conclusions: Additionally, besides excluding subjectivity, the up to now unreported cases of 3 + 0, 4 + 0, and 5 + 0 Allred scores were detected only by the application of the proposed quantitative approach.

Abstract P5-05-04: Myc as a poor prognostic marker for ER+ inflammatory breast cancer (IBC): Quantitative estrogen receptor (ER) expression analysis and gene expression analysis in ER+ IBC vs non-IBC

Abstract Background Estrogen receptor-positive (ER+) primary inflammatory breast cancer (IBC) has a poorer prognosis than ER+ primary non-IBC. Our objective was to determine the association between ER positivity and survival outcome in order to elucidate the biological reason that ER+ IBC is more aggressive than non-IBC. Methods We retrospectively determined the relationship between ER expression by immunohistochemistry staining and neoadjuvant chemotherapy response as well as survival outcome for 189 patients with ER+ and HER2-negative (HER2-) IBC and 896 case-matched patients with stage III non-IBC seen at MD Anderson Cancer Center between January 1989 and April 2015. We performed gene expression (GE) analysis for 39 patients with ER+/HER2- IBC and 40 patients with non-IBC to detect genes that are specifically overexpressed in IBC. Logistic regression and Cox proportional hazards model were used to determine the predictive and prognostic value of percentages of cells positive for ER and progesterone receptor (PR) among the patients with ER+/HER2- IBC and non-IBC. Recursive partitioning analysis (RPA) was used to determine the optimal cutoff points for ER% and progesterone receptor (PR) % that maximized differences in survival. The identified cutoff points were tested in an external cohort of 192 ER+/HER2- IBC patients from Institut Paoli-Calmettes in France. Results The median values for ER% for IBC and non-IBC were 85 (range, 1-100) and 90 (range, 1-100), respectively. The logistic regression model demonstrated a lack of a relationship of ER% with pathological complete response rate to neoadjuvant chemotherapy both in IBC (P=0.29) and non-IBC (P=0.14). Expression of ER was significantly associated with distant disease-free survival (DDFS); hazard ratio (HR), 0.56 [95% CI, 0.37-0.83] per 50% increase in ER%; P&amp;lt;0.05). Also, ER% was significantly associated with overall survival (OS) (HR, 0.40 [95% CI, 0.25-0.63] per 50% increase in ER%; P&amp;lt;0.05). RPA showed that 91.5% and 9.0% were the optimal cutoff points for ER% and PR%, respectively, for DDFS and overall survival in IBC patients. However, the cutoff points could not be validated in the French external cohort. In the GE study, 84 genes were detected as significantly distinguishing ER+ IBC from non-IBC. Among the top 15 canonical pathways shown by IPA, the ERK/MAPK signaling pathway, PDGF pathway, insulin receptor signaling pathway, and IL-7 signaling pathway were associated with the ER signaling pathway. MYC upregulation was observed in three of these four pathways. Indeed, ER+/HER- IBC had significantly higher MYC amplification compared to those with non-IBC (P&amp;lt;0.05) and higher MYC level was associated with poor relapse free survival for IBC (HR, 1.85 [95% CI, 1.05-2.70], P&amp;lt;0.05). Conclusions Increased ER positivity was significantly associated with improved survival in ER+/HER- IBC patients. ER+/HER- IBC had several activated pathways with MYC upregulation compared to non-IBC. MYC upregulation was associated with a poor survival outcome for ER+/HER- IBC. The results indicate that MYC is a key gene for understanding the aggressive biological behavior of ER+/HER- IBC. Citation Format: Iwase T, Harano K, Masuda H, Kida K, Espinosa Fernandez JR, Hess KR, Wang Y, Woodward WA, Layman RM, Dirix L, Van Laere SJ, Bertucci F, Ueno NT. Myc as a poor prognostic marker for ER+ inflammatory breast cancer (IBC): Quantitative estrogen receptor (ER) expression analysis and gene expression analysis in ER+ IBC vs non-IBC [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-05-04.

Molecular subtype approximated by quantitative estrogen receptor, progesterone receptor and Her2 can predict the prognosis of breast cancer.

To investigate the clinicopathological characteristics and prognosis of breast cancer subtypes classified by quantitative estrogen receptor (ER), progesterone receptor (PR), and Her2. 923 patients with primary breast cancer having a median age of 53 years who were treated at the Cancer Hospital of Fudan University in Shanghai between January 2002 and June 2004 were retrospectively analyzed. Four molecular subtypes were constructed from the immunohistochemical results of quantitative hormone receptor (HR) and Her2 status. HR+ was defined as ER+ and PR+, HR+/- as ER/PR+ at lower levels or lacking either ER or PR, and HR- as both ER- and PR-. The four subtypes were HR+/Her2-, HR+/-/Her2-, HR-/Her2- (triple-negative), and Her2+. Clinical and pathological parameters, disease-free survival (DFS), and overall survival (OS) measurements were compared between patients with different molecular subtypes. The proportions of HR+/Her2-, HR+/-/Her2-, triple-negative, and Her2+ breast cancer were 36.6% (338/923), 22.9% (211/923), 20.6% (190/923), and 19.9% (194/923). The median follow-up was 49.0 months (4-77 months). In 145 cases disease recurrence or death occurred. In multivariate analysis with the HR+/Her2- subtype taken as the reference category, triple-negative and Her2+ subtypes were associated with increased recurrence and death with a hazard ratio (HR) of 2.05 (95% CI 1.31-3.20; P = 0.002) and 1.89 (95% CI 1.20-2.97, P = 0.006) for DFS and 2.84 (95% CI 1.45-5.55; P = 0.002) and 2.95 (95% CI 1.51-5.77, P = 0.002) for OS, respectively; the HR+/-/Her2- subtype was marginally associated with poor prognosis with HR 1.51 (95% CI 0.94-2.43; P = 0.088) and 1.90 (95% CI 0.92-3.94; P = 0.084) for DFS and OS, respectively. Breast cancer subtypes based on quantitative ER, PR, and Her2 may be predictive of prognosis. Patients whose tumors were not HR+/Her2- had a worse outcome in our study.

A comparison of genomic assays in determining risk of late recurrence and benefit of extended endocrine therapy (EET).

e12045 Background: Breast cancer patients who are ER positive, lymph node negative have the best overall prognosis. However 50% of recurrences occur after 5 years. The Breast Cancer Index (BCI) is a gene expression-based biomarker that provides an individual risk of distant recurrence and benefit of EET based on a continuous risk model. (1) The BCI may help with clinical decisions regarding EET since prolonged therapy may have an increase in side effects including uterine cancer, DVT, myalgias and bone loss. The OncotypeDX is a 21 gene assay that predicts recurrence with a recurrence score. A recent study by Wolmark et al. evaluated the use of quantitative Estrogen Receptor Index (ESRI) combined with RS and found that RS was prognostic in patients with higher quantitative ESRI, suggesting EET be used for patients with intermediate and high RS with ESR1 expression &gt; 9.1. (2) Methods: 20 patients, ER positive, node negative who had the BCI and ONC-DX performed were evaluated in this retrospective IRB approved review. Results: Using ESRI alone 85% of patients would be recommended to continue an additional 5 years of EET. Using BCI this number was reduced to 35%. Conclusions: Comparing both the risk of recurrence and benefit of ETT, ESRI and BCI were concordant only 37.5% of the time. The cost of extended adjuvant therapy with Anastrazole ($190/mos x 60 mos = $11,400) or Tamoxifen ($50/mos x 60 mos = $ 3,000) would have resulted in a cost savings of $79,800 (Anastrazole) or $21,000 (Tamoxifen) for this small group of patients. Utilization of the BCI (cost $ 3416.00) may be a cost effective and accurate genomic approach in determining the use of EET and avoiding concomitant side effects.

The role of quantitative estrogen receptor status in predicting tumor response at surgery in breast cancer patients treated with neoadjuvant chemotherapy.

Estrogen receptor (ER) negative (-) breast cancer (BC) patients have better tumor response rates than ER-positive (+) patients after neoadjuvant chemotherapy (NCT). We conducted a retrospective review using the institutional database "Biomatrix" to assess the value of quantitative ER status in predicting tumor response at surgery and to identify potential predictors of survival outcomes. Univariate followed by multivariable regression analyses were conducted to assess the association between quantitative ER and tumor response assessed as tumor size reduction and pathologic complete response (pCR). Predictors of recurrence-free survival (RFS) were identified using a cox proportional hazards model (CPH). A log-rank test was used to compare RFS between groups if a significant predictor was identified. 304 patients were included with a median follow-up of 43.3months (Q1-Q3 28.7-61.1) and a mean age of 49.7years (SD 10.9). Quantitative ER was inversely associated with tumor size reduction and pCR (OR 0.99, 95% CI 0.99-1.00, p=0.027 and 0.98 95% CI 0.97-0.99, p<0.0001, respectively). A cut-off of 60 and 80% predicted best the association with tumor size reduction and pCR, respectively. pCR was shown to be an independent predictor of RFS (HR 0.17, 95% CI 0.07-0.43, p=0.0002) in all patients. At 5years, 93% of patients with pCR and 72% of patients with residual tumor were recurrence-free, respectively (p=0.0012). Quantitative ER status is inversely associated with tumor response in BC patients treated with NCT. A cut-off of 60 and 80% predicts best the association with tumor size reduction and pCR, respectively. Therefore, patients with an ER status higher than the cut-off might benefit from a neoadjuvant endocrine therapy approach. Patients with pCR had better survival outcomes independently of their tumor phenotype. Further prospective studies are needed to validate the clinical utility of quantitative ER as a predictive marker of tumor response.

Abstract P6-09-12: A consecutive series of early breast cancers with a low estrogen receptor expression

Abstract P6-09-12: A consecutive series of early breast cancers with a low estrogen receptor expression

Abstract P6-09-39: The role of quantitative estrogen receptor status in predicting breast tumor response to neoadjuvant chemotherapy

Abstract Introduction: Patients with Estrogen Receptor negative breast cancer (BC) are known to have higher tumor response rates than ER positive patients when treated with neoadjuvant chemotherapy (NCT). Few studies have assessed ER status as a quantitative continuous measure in predicting tumor response in this setting. We aimed to study the association between quantitative ER status and tumor response at surgery in BC patients treated with NCT at our institution, and identify potential predictors of better survival outcomes. Methods: A retrospective review using a neoadjuvant BC database (The "Sunnybrook Biomatrix") identified 304 eligible patients that were included in the analyses. A univariate followed by a multivariable logistic regression analyses were conducted to assess the association between quantitative ER (expressed in percentage) and tumor response (good vs. poor response defined as &amp;lt; vs. ≥ 50% reduction in tumor size) while controlling for potential confounders. For the secondary outcome, the Kaplan Meier method was used to estimate the recurrence free survival (RFS) in this cohort. Predictors of RFS were identified using a cox proportional hazards model (CPH) to adjust for clinically relevant variables. A log-rank test was used to compare RFS between groups for any significant binary predictor. Results: The median follow up of all patients was 43.3 months (Q1-Q3: 28.7-61.1). Quantitative ER was inversely associated with tumor response in a multivariable logistic regression model (Odds Ratio 0.99 95%CI: 0.99-1.00, p=0.027). A cut-off of 60% seemed to best predict the association based on the c-statistic (c=0.67) and the receiver operating characteristic curve. However, quantitative ER was not associated with RFS; pathologic complete response (pCR) was shown to be an independent predictor of RFS in a CPH model (Hazard Ratio: 0.17, 95% CI: 0.07, 0.43, p=0.0002) in all patients, after controlling for potential confounders. At 5 years, 93% of patients with pCR and 72% of patients with residual tumor (no pCR) were recurrent-free respectively (log-rank test p=0.0012). Conclusion: This study suggests that BC patients with ER status &amp;lt; 60% are more likely to respond to NCT. Although ER status itself did not predict for relapse-free survival, patients with a pCR had better RFS, and this association was seen amongst all tumor phenotypes. The role of quantitative ER in predicting and maximizing tumour response to NCT (including optimizing pCR rate) needs to be better defined in prospective studies. Key words: Estrogen receptors, breast cancer, quantitative, tumor response, pathologic complete response. Citation Format: Raphael J, Trudeau M, Paramsothy T, Lee N, Gandhi S. The role of quantitative estrogen receptor status in predicting breast tumor response to neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-39.

Prognostic Impact of the Combination of Recurrence Score and Quantitative Estrogen Receptor Expression (ESR1) on Predicting Late Distant Recurrence Risk in Estrogen Receptor-Positive Breast Cancer After 5 Years of Tamoxifen: Results From NRG Oncology/National Surgical Adjuvant Breast and Bowel Project B-28 and B-14.

We determined the utility of the 21-Gene Recurrence Score (RS) in predicting late (> 5 years) distant recurrence (LDR) in stage I and II breast cancer within high and low-ESR1-expressing groups. RS was assessed in chemotherapy/tamoxifen-treated, estrogen receptor (ER) -positive, node-positive National Surgical Adjuvant Breast and Bowel Project B-28 patients and tamoxifen-treated, ER-positive, node-negative B-14 patients. The association of the RS with risk of distant recurrence (DR) 0 to 5 years and those at risk > 5 years was assessed. An ESR1 expression cut point was optimized in B-28 and tested in B-14. Median follow-up was 11.2 years for B-28 and 13.9 years for B-14. Of 1,065 B-28 patients, 36% had low (< 18), 34% intermediate (18 to 30), and 30% high (≥ 31) RS. Of 668 B-14 patients, 51% had low, 22% intermediate, and 27% high RS. Median ESR1 expression by reverse transcriptase polymerase chain reaction was: B-28, 9.7 normalized expression cycle threshold units (CT) and B-14, 10.7 CT. In B-28, RS was associated with DR 0 to 5 years (log-rank P < .001) and > 5 to 10 years (log-rank P = .02) regardless of ESR1 expression. An ESR1 expression cut point of 9.1 CT was identified in B-28. It was validated in B-14 patients for whom the RS was associated with DR in years 5 to 15: 6.8% (95% CI, 4.4% to 10.6%) versus 11.2% (95% CI, 6.2% to 19.9%) versus 16.4% (95% CI, 10.2% to 25.7%) for RS < 18, RS 18 to 30, and RS ≥ 31, respectively (log-rank P = .01). For LDR, RS is strongly prognostic in patients with higher quantitative ESR1. Risk of LDR is relatively low for patients with low RS. These results suggest the value of extended tamoxifen therapy merits evaluation in patients with intermediate and high RS with higher ESR1 expression at initial diagnosis.

Abstract P5-08-09: Differential patient stratification by the breast cancer index HoxB13/IL17BR ratio vs recurrence score (RS) plus quantitative ER expression in hormone receptor positive, node negative breast cancer

Abstract Background: Second generation genomic biomarkers for patients with early stage breast cancer are based on integration of proliferative and estrogen signaling-related gene expression, which has led to data applicable in the extended (post-5 year) endocrine therapy setting. The Breast Cancer Index (BCI) assay interrogates these two signaling pathways, significantly stratified patients into high (13.4%) or low (3.5%) risk of late (5-10y) distant recurrence in TransATAC , and includes a gene expression signature (HoxB13/IL17BR, H/I) that predicted benefit from extended endocrine therapy in MA.17. The 21-gene assay has recently been investigated in combination with quantitative estrogen receptor (qER) expression, wherein a subset of approximately 20% of patients with a high recurrence score (RS) and qER above 9.1 had a higher prognostic risk for late distant recurrence (12.6%) than those with Low RS (4.7%) or intermediate RS (4.1%) (Wolmark, ASCO 2014). The objective of this study was to compare patient stratification with H/I and RS+qER. Methods: Consecutive cases submitted for BCI clinical testing from lymph node-negative breast cancer patients with available RS scores and qER &amp;gt;9.1 abstracted from pathology reports (N=115) were analyzed. Cohen's kappa statistic was used to test agreement between H/I and RS+qER for patient stratification. Results: No statistically significant agreement was observed between H/I stratification and RS+qER prognostic risk stratification with respect to identifying patients for extended endocrine therapy (Cohen's kappa = -0.002, p = 0.51). H/I identified 36 cases (34%) as High likelihood to benefit from extended endocrine therapy compared to 3 cases (3%) classified as by RS+qER as having high risk of late recurrence (Table). Of the 69 cases (66%) classified as RS+qER Low risk, 19 were identified as High likelihood to benefit from extended endocrine therapy by H/I. Table Low H/I PredictiveHigh H/I PredictiveTotalRS+qER Low Risk50 (48%)19 (18%)69 (66%)RS+qER Inter Risk17 (16%)16 (15%)33 (31%)RS+qER High Risk2 (2%)1 (1%)3 (3%)Total69 (66%)36 (34%) Conclusions: This retrospective analysis of clinical cases shows that H/I and RS+qER identify distinct subsets of patients, and highlights that the underlying biology of risk stratification differs from that of endocrine responsiveness. Comparatively, findings indicate that the H/I identifies additional patients that may be considered for extended endocrine therapy. Citation Format: Naughton MJ, Schroeder BE, Operana TN, Zhang Y, Schnabel CA. Differential patient stratification by the breast cancer index HoxB13/IL17BR ratio vs recurrence score (RS) plus quantitative ER expression in hormone receptor positive, node negative breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-08-09.

Quantitative ER and PgR Assessment as Predictors of Benefit from Lapatinib in Postmenopausal Women with Hormone Receptor–Positive, HER2-Negative Metastatic Breast Cancer

Lapatinib, a dual epidermal growth factor receptor (EGFR) and HER2 inhibitor, remains unproven in non-HER2-amplified metastatic breast cancer (MBC). EGF30008, a phase III trial of letrozole and lapatinib versus letrozole and placebo, demonstrated that lapatinib significantly improves outcome for postmenopausal women with HER2-amplified, but not HER2-negative, MBC. The hypothesis that low hormone receptor status is associated with benefit in this HER2-negative cohort was tested. A blinded retrospective biomarker evaluation used immunohistochemistry (IHC) to semiquantify estrogen receptor (ER) and progesterone receptor (PgR) expression (n = 821/952). HER2 status was determined by IHC and confirmed by FISH (n = 326). Effects of these biomarkers on progression-free survival (PFS) were examined in patients with available tissue. In HER2-negative, ER-positive MBC, median PFS was analyzed by ER and PgR expression (H-score) by quartile (Q). There was significant improvement in patients with low ER expression (Q1, H-score <160) with lapatinib and letrozole (13.6 vs. 6.7 months; P = 0.01). No benefit was associated with stronger ER expression (Q2/3, H-score ≥ 160 and <250; 13.6 vs. 14.2 months; Q4, H-score ≥ 250; 11.2 vs. 14.2 months). There was no association between PgR H-score and benefit from lapatinib. In postmenopausal patients with advanced hormone receptor-positive disease, weak ER expression is associated with worse outcome with letrozole treatment compared with the combination. The addition of lapatinib significantly improved PFS for this patient subgroup and augments data supporting interaction between steroid hormone and peptide hormone signaling. A prospective study validating this hypothesis is required.

Abstract P3-05-08: Discordance in hormone receptor (HR) assessment by IHC and RT-PCR in an estrogen receptor (ER) low-positive group (1-10% positive cells): Does accurate assessment of HR status require dual testing?

Abstract Background: Accurate determination of hormone receptor (ER/PR) and HER2 status is critical for making treatment (Tx) decisions in early stage breast cancer (EBC) patients (pts). ASCO/CAP guidelines categorize pts with &amp;gt;1% ER/PR staining as ‘positive’ for HR expression. A formal interaction between quantitative ER expression by RT-PCR and tamoxifen response was demonstrated in NSABP B-14 (Kim C, JCO, 2011). Prognosis and Tx decisions depend on the status of ER expression and pts with ER(-) disease have a worse prognosis. A comparative study to evaluate ASCO/CAP cutoffs for ER protein expression and prospectively validated ER mRNA expression by RT-PCR was undertaken in consecutive EBC pts with either negative or low-positive ER by IHC from a single institution. Methods: Consecutive EBC pts with IHC defined ER(-) (&amp;lt;1% positive cells) or ER low-positive (1-10% positive cells; by ASCO/CAP guidelines) were identified at New York University School of Medicine. ER, PR and HER2 protein assessment used standard IHC methods (SP1, 1E2, 4B5, Ventana). ER, PR and HER2 mRNA assessment used the Oncotype DX® 21-gene assay, reference-normalized expression measurements ranged from 0 to 15, where each 1-unit increase reflects about a two-fold increase in RNA. The validated thresholds for positivity for the three markers were used: ER, 6.5, PR, 5.5 and HER2, 11.5. Descriptive statistics were calculated for baseline characteristics, and two-way classification tables were produced for ER by IHC versus RT-PCR. Results: Of 140 IHC evaluable samples, 106 (76%) were ER(-), 34 (24%) were ER low-positive, 116 (83%) PR(-), and 24 (17%) PR+. Pts included showed: 69.3% ≥50 yrs; 83.6% had poor differentiation; 31.2% had ≥1 positive nodes; 34.3% were ≥ 2.0cm. 37 pts (26.4%) were HER2+ by IHC or FISH. The cross classification of ER status by RT-PCR versus IHC is in the Table. For IHC ER(-) cases there was a 93.3% percent negative agreement (PNA) between IHC and RT-PCR. For IHC ER low-positive cases the percent positive agreement (PPA) was 38.2% between IHC and RT-PCR. ER expression (CT units) ranged from 2.8 to 8.3 for IHC negative cases and 3.4 to 9.2 for IHC low-positive cases. Conclusions: The status of ER, PR and HER2 is critical for Tx decision making in pts with EBC. In this cohort of ER(-) or low-positive expressing EBC cases there was high agreement between IHC and RT-PCR for negative ER expression (93% PNA); however, only 40% of ER- low-positive (1-10%) cases by IHC were positive by RT-PCR. While many of the discordant cases were near the RT-PCR cutpoint of 6.5, about 10% of the discordances were either strongly ER+ or strongly ER(-) by RT-PCR suggesting misclassification by central IHC. Thus, in many IHC ER- low-positive cases there may be little or no benefit from the addition of hormonal therapy. Accurate assessment of ER is critically important to ensure the best Tx and these findings indicate that dual testing of low-positive ER by IHC merits consideration and additional study. ER StatusIHCRT-PCRNegativeLow-positiveTotalNegative99 (93.3%)21 (61.7%)120 (85.7%)Positive7 (6.6%)13 (38.2%)20 (14.3%)Total106 (100%)34 (100%)140 (100%) Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-05-08.

BIK/NBK gene as potential marker of prognostic and therapeutic target in breast cancer patients

The purpose of this study is to determine the association between the BIK/NBK gene expression and estrogen receptor alpha expression. We determined the association of BIK/NBK gene expression by real time quantitative reverse transcription polymerase chain reaction and estrogen receptor alpha expression by immunohistochemistry in samples of breast cancer tissue. We found a statistically significant correlation of BIK/NBK gene expression with the estrogen receptor alpha expression (ρ=0.751, p=0.004). For verify differences of BIK/NBK gene expression among ERα+ and ERα- breast cancer tissues, Mann-Whitney U test was performed, obtaining significant differences. BIK/NBK gene expression may have important clinical implications and provide predictive, prognostic or therapeutic marker in breast cancer patients according to the estrogen receptor alpha expression.

P5-13-19: Borderline Estrogen and Progesterone Receptor Expression and Efficacy of Anti-Estrogen Therapy Analyzed by Subpopulation Treatment Effect Pattern Plot Analysis.

Abstract Background: The American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) recently recommended that estrogen receptor (ER) and progesterone receptor (PR) values be considered positive in the evaluation of breast cancer specimens if there are at least 1% positive tumor nuclei by immunohistochemisty (IHC) scoring. This change constitutes a lower cutoff value than the 5% or 10% widely used in the past and increases the number of patients that can now be treated with anti-estrogen therapy, a therapy which carries significant treatment efficacy and a favorable toxicity profile. Despite the new recommendation however, it remains unclear if patients whose tumors display borderline ER and/or PR expression truly benefit from anti-estrogen therapy. Methods: We examined a total of 608 patient samples from the OHSU Knight Cancer Institute Breast Cancer Tissue Repository for which we have quantitative ER and PR information and their clinical outcome. Of those, 282 patients did not receive any systemic treatment and 165 received anti-estrogen therapy (the majority tamoxifen). Cytosolic steroid hormone receptors were quantitated by conventional steroid binding assay and Scatchard plot analysis or by enzyme-linked immunoassay system. For immunoassays, human estrogen receptor (ER) and progesterone receptor (PR) kits were obtained from Abbott Laboratories and assays were conducted according to manufacturer's specification. We performed subpopulation treatment effect pattern plot (STEPP) analysis to explore the presence of interaction between treatment effects and quantitative ER and PR levels. Clinical outcome used in this study includes 5-year overall survival and 5-year breast cancer free interval. Results: Multi-variate analysis finds neither ER nor PR expression adjusted by treatment status is associated with either overall survival (P= 0.20, median follow up of 63 months) or breast cancer free interval (P= 0.82, median follow up of 60 months). For both ER and PR, there is no interaction between treatment outcome (5 year survival probability) and levels of hormone receptor expression based on Kaplan-Meier estimate (P=0.36 and P= 0.65, respectively). Patients with borderline ER expression appear to benefit from anti-estrogen therapy while patients with borderline PR expression appear to have worse outcome with anti-estrogen therapy. Conclusions: Though descriptive in nature, our STEPP analysis provides support for the recommendation by ASCO and CAP to lower the cutoff for ER positivity in breast cancer specimens. There is overall no interaction between the level of hormone receptor and treatment benefit for all patients from low ER to high ER. Therefore, treatment will benefit all patients including those with low ER levels. Extending hormone therapies to the group of patients whose tumors express borderline PR values, however does not seem to confer therapeutic benefit. More study is needed to determine the benefits of offering anti-estrogen therapy to patients whose tumors express low PR. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-13-19.

A New Molecular Predictor of Distant Recurrence in ER-Positive, HER2-Negative Breast Cancer Adds Independent Information to Conventional Clinical Risk Factors

According to current guidelines, molecular tests predicting the outcome of breast cancer patients can be used to assist in making treatment decisions after consideration of conventional markers. We developed and validated a gene expression signature predicting the likelihood of distant recurrence in patients with estrogen receptor (ER)-positive, HER2-negative breast cancer treated with adjuvant endocrine therapy. RNA levels assessed by quantitative reverse transcriptase PCR in formalin-fixed, paraffin-embedded tumor tissue were used to calculate a risk score (Endopredict, EP) consisting of eight cancer-related and three reference genes. EP was combined with nodal status and tumor size into a comprehensive risk score, EPclin. Both prespecified risk scores including cutoff values to determine a risk group for each patient (low and high) were validated independently in patients from two large randomized phase III trials [Austrian Breast and Colorectal Cancer Study Group (ABCSG)-6: n = 378, ABCSG-8: n = 1,324]. In both validation cohorts, continuous EP was an independent predictor of distant recurrence in multivariate analysis (ABCSG-6: P = 0.010, ABCSG-8: P < 0.001). Combining Adjuvant!Online, quantitative ER, Ki67, and treatment with EP yielded a prognostic power significantly superior to the clinicopathologic factors alone [c-indices: 0.764 vs. 0.750, P = 0.024 (ABCSG-6) and 0.726 vs. 0.701, P = 0.003 (ABCSG-8)]. EPclin had c-indices of 0.788 and 0.732 and resulted in 10-year distant recurrence rates of 4% and 4% in EPclin low-risk and 28% and 22% in EPclin high-risk patients in ABCSG-6 (P < 0.001) and ABCSG-8 (P < 0.001), respectively. The multigene EP risk score provided additional prognostic information to the risk of distant recurrence of breast cancer patients, independent from clinicopathologic parameters. The EPclin score outperformed all conventional clinicopathologic risk factors.

Molecular Subtype Approximated by Quantitative Estrogen Receptor, Progesterone Receptor and Her2 Can Predict the Prognosis of Breast Cancer

To investigate the clinicopathological characteristics and prognosis of breast cancer subtypes classified by quantitative estrogen receptor (ER), progesterone receptor (PR), and Her2. 923 patients with primary breast cancer having a median age of 53 years who were treated at the Cancer Hospital of Fudan University in Shanghai between January 2002 and June 2004 were retrospectively analyzed. Four molecular subtypes were constructed from the immunohistochemical results of quantitative hormone receptor (HR) and Her2 status. HR+ was defined as ER+ and PR+, HR+/- as ER/PR+ at lower levels or lacking either ER or PR, and HR- as both ER- and PR-. The four subtypes were HR+/Her2-, HR+/-/Her2-, HR-/Her2- (triple-negative), and Her2+. Clinical and pathological parameters, disease-free survival (DFS), and overall survival (OS) measurements were compared between patients with different molecular subtypes. The proportions of HR+/Her2-, HR+/-/Her2-, triple-negative, and Her2+ breast cancer were 36.6% (338/923), 22.9% (211/923), 20.6% (190/923), and 19.9% (194/923). The median follow-up was 49.0 months (4-77 months). In 145 cases disease recurrence or death occurred. In multivariate analysis with the HR+/Her2- subtype taken as the reference category, triple-negative and Her2+ subtypes were associated with increased recurrence and death with a hazard ratio (HR) of 2.05 (95% CI 1.31-3.20; P = 0.002) and 1.89 (95% CI 1.20-2.97, P = 0.006) for DFS and 2.84 (95% CI 1.45-5.55; P = 0.002) and 2.95 (95% CI 1.51-5.77, P = 0.002) for OS, respectively; the HR+/-/Her2- subtype was marginally associated with poor prognosis with HR 1.51 (95% CI 0.94-2.43; P = 0.088) and 1.90 (95% CI 0.92-3.94; P = 0.084) for DFS and OS, respectively. Breast cancer subtypes based on quantitative ER, PR, and Her2 may be predictive of prognosis. Patients whose tumors were not HR+/Her2- had a worse outcome in our study.

Impact of the mode of estrogen receptor determination on breast cancer prognosis

e11609 Background: Impact of the mode of estrogen receptor determination on breast cancer prognosis Abstract Background: We examined if the mode of estrogen receptor (ER) determination and expression in primary breast cancer impact on patient's prognosis. Methods: We conducted an analysis on a prospective cohort of 1012 patients treated for stage I-III Breast Cancer at Conception Hospital, Marseille, France between 1984 to 2003. ER was determined according to enzyme immuno-assay (EIA) and immunohistochemistry (IHC). Disease-free and overall survivals were evaluated according to the mode of ER quantification and in function of qualitative or quantitative ER expression. Results: ER was a strong predictor of overall survival in the whole population whatever method used for the status determination (p&lt;0.001); however when stratifying the analysis on ER quantitative expression, ER was still a prognostic indicator in the EIA group for OS (p= 0.004) and DFS (p&lt;0.001), group but not in the IHC group for OS (p=0.58) and DFS (p= 0.195). Conclusions: ER determination in breast cancer is strongly associated with a better prognosis, but the level of influence of ER varies with the assay and ER expression. No significant financial relationships to disclose.

Progression-free survival (PFS) of patients with HER2-negative, estrogen-receptor (ER)-low metastatic breast cancer (MBC) with the addition of lapatinib to letrozole: Biomarker results of EGF30008

1018 Background: Lapatinib (Lap), an oral, dual inhibitor of EGFR/HER-2, is approved with capecitabine for treatment of HER-2+ MBC for recurrence after taxane, anthracycline, and trastuzumab-based therapy. Letrozole (Let) has activity in hormone-receptor positive (HR+) BC. It has been hypothesized that peptide growth factor signaling and hormone signaling pathways interact and dual targeting of these pathways results in therapeutic synergy. We report a blinded analysis of HER-2, ER, and progesterone receptor (PR) expression for patients (pts) with HR+ MBC at first diagnosis or post-adjuvant relapse and response to Lap + Let versus Let. Methods: 1286 pts were randomized 1:1 to 2.5 mg Let daily plus either 1500 mg Lap daily or placebo. The primary endpoint was PFS in HR+, HER-2+ MBC pts; secondary endpoints included PFS in the intent-to-treat population. Blinded, centralized commerical laboratory analysis of archived tumor tissue for HER-2 (IHC and/or FISH) and academic laboratory semi-quantitative analysis of ER/PR (IHC, H-score) was performed and correlated with clinical outcome. Results: In 219/1286 (17%) HER-2+ (FISH+ or IHC3+) pts, a significant improvement in median PFS was observed for Lap + Let versus Let (8.2 v 3.0 mos, HR = 0.71, 95% CI 0.53, 0.96, p = 0.019). No significant difference in median PFS was seen in 952 (74%) HER-2-negative pts (13.4 v 13.7 mos, HR = 0.90, 95% CI 0.77, 1.05, p = 0.188). 821/952 (86%) HER-2-negative pts had tissue available for quantitative ER and PR analysis. Analysis of ER and PR by quartile identified a subgroup of HER-2-negative pts that benefitted from adding Lap to Let. Pts with the lowest quartile of ER expression (H-score &lt;160, n = 207) had a significant improvement in median PFS (13.6 mos v 6.6 mos, HR = 0.65, 95% CI 0.47, 0.9, p &lt; 0.005). Pts with higher levels of ER did not significantly benefit from adding Lap to Let. Analysis of PR expression did not identfiy a subgroup that benefited from Lap. Conclusions: Pts with HER-2-negative, ER+ MBC and low ER expression may benefit from the addition of lap to let. Additional analyses of EGFR, other biomarkers, and prior hormone therapy will be presented. [Table: see text]

Relationship Between Quantitative Estrogen and Progesterone Receptor Expression and Human Epidermal Growth Factor Receptor 2 (HER-2) Status With Recurrence in the Arimidex, Tamoxifen, Alone or in Combination Trial

To determine the relationship between quantitative estrogen-receptor (ER) and progesterone-receptor (PgR) expression and human epidermal growth factor 2 (HER-2) status with time to recurrence (TTR) in postmenopausal women with hormone receptor-positive primary breast cancer treated with anastrozole or tamoxifen as adjuvant therapy. Formalin-fixed, paraffin-embedded tumor blocks were retrospectively collected from patients in the monotherapy arms of the Arimidex, Tamoxifen Alone or in Combination (ATAC) trial and centrally tested for ER, PgR and HER-2. ER and PgR were scored using continuous scales and HER-2 was scored as 0 to 3+ with 2+ cases being analyzed by fluorescence in situ hybridization. Blocks were collected from 2,006 of 5,880 eligible patients. Tissue was assessable and ER and/or PgR positivity confirmed centrally in 1,782 cases. In these, TTR was longer for anastrozole than for tamoxifen by a similar extent to that in the overall trial. None of the three biomarkers identified a set of patients with differential benefit from anastrozole over tamoxifen. Patients with low ER, low PgR, and high HER-2 expression had a poorer prognosis with either drug. Only 2.6% of patients in the highest quartile of PgR experienced recurrence after 5 years, compared with 13.2% in the lowest quartile. Quantitative expression of ER and PgR and HER-2 status did not identify patients with differential relative benefit from anastrozole over tamoxifen: TTR was longer for anastrozole than for tamoxifen in all molecular subgroups. Low ER or PgR or high HER-2 expression are associated with a high risk of recurrence with either anastrozole or tamoxifen.