Diagnostic Core Needle Biopsy Research Articles

Abstract PO4-08-09: Concordance analysis of paired breast cancer core needle biopsies and surgical excision samples using the Oncotype DX Breast Recurrence Score® assay

Abstract INTRODUCTION: The Oncotype DX Breast Recurrence Score® (RS) assay is validated to predict risk of distant recurrence at 10 years and the benefit of adjuvant chemotherapy in patients with estrogen receptor (ER)+, HER2- early breast cancer who receive 5 years of endocrine therapy. The feasibility of Oncotype DX® testing with diagnostic core needle biopsies (CNB) was demonstrated through analysis of a large commercial laboratory experience. The neoadjuvant ADAPT study showed the clinical utility of deriving the Recurrence Score® (RS) result from CNB as well. However, data are limited on concordance of RS results from paired CNB and surgical samples. Our primary objective was to determine the degree of concordance of RS results between paired tissue samples from the same primary breast tumor of patients with early stage, ER+, HER2- invasive breast cancer who had a CNB and subsequent surgical excision (SE; lumpectomy or mastectomy) without intervening systemic therapy. METHODS: Patients with a commercial RS result on either CNB or subsequent SE were identified through medical record and clinical database review. A pathologist reviewed archival tissue samples to confirm eligibility and selected the other paired CNB or SE block most representative of the tumor tissue for subsequent study Oncotype DX testing. Descriptive statistics were used to summarize patient and tumor characteristics. Wilcoxon signed rank, McNemar’s and Cochran-Mantel-Haenszel tests were used to compare RS between SE and CNB paired samples. Cohen’s Kappa and 95% confidence intervals (CIs) were used to compare the agreement of categorical RS (0-25 and 26-100) result between SE and CNB paired samples. Lin’s concordance correlation and 95% CIs were used to compare agreement of continuous RS between paired samples. RESULTS: A total of 134 patients were identified with paired CNB and SE samples with a median time of 34 (range 5-103) days between collections. Of the 134 patients, a commercial RS result was available for 25 (18.7%) with CNB and 109 (81.3%) with SE. A study RS result was then generated on the other paired sample. Median age was 62 years (range 33-99; 23 patients [17%] were age ≤50 vs. 111 [83%] age >50). Cases were predominantly node negative (107/134 node negative vs. 26/134 node positive; 1/134 unknown) invasive ductal carcinomas (104/134 ductal vs. 18/134 classic lobular vs. 12/134 other). Mean RS results were 15.6 (range 0-56) and 16.6 (range 0-59) for CNB and SE, respectively (p = 0.003), with no statistically significant differences in RS category defined as low vs. high risk (119/134 CNB vs. 114/134 SE for RS 0-25 and 15/134 CNB vs 20/134 SE for RS 26-100; p = 0.13) or low vs. intermediate vs. high risk (85/134 CNB vs. 78/134 SE for RS 0-17 and 43/134 CNB vs. 48/134 SE for RS 18-30 and 6/134 CNB vs. 8/134 SE for RS 31-100; p = 0.19). No differences were observed based on age relative to 50 years or nodal status (data not shown). Cohen’s Kappa statistic k = 0.64 (95% CI, 0.44-0.83) supports substantial agreement between the CNB and SE samples. Lin’s concordance correlation coefficient (CCC) demonstrates similar agreement for the continuous RS result between paired samples (CCC = 0.86 [0.80-0.90]). Overall percent agreement was 91.8% (87.1-96.4%). CONCLUSIONS: Studies evaluating the level of concordance of ER, progesterone receptor, and HER2 biomarker status between CNB and SE samples have found high concordance rates, albeit varied. We now provide data demonstrating high concordance of RS results between CNB and SE specimens obtained from the same breast primary tumor without intervening systemic therapy. This supports use of either biopsy source for testing with a genomic predictor to identify those patients who will most likely benefit from chemotherapy and which patients may be spared. Citation Format: Aziza Nassar, Jodi Carter, Paige Innis, Satish Seerapu, Christy Russell, Helena Hanna, Abigail Lochala, Minetta Liu. Concordance analysis of paired breast cancer core needle biopsies and surgical excision samples using the Oncotype DX Breast Recurrence Score® assay [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 PO4-08-09.

Use of the Gene Expression Test Prosigna® in Premenopausal Patients with HR+, HER2− Early Breast Cancer: Correlation of the Results with the Proliferation Marker Ki-67

Introduction: In hormone receptor-positive (ER+/PR+) and human epidermal growth factor receptor 2-negative (HER2−) early-stage breast cancer (EBC), gene expression tests such as the Prosigna are increasingly used since classic clinicopathological parameters and the proliferation factor Ki-67 often do not allow a definite therapy decision regarding an adjuvant chemotherapy. While the Prosigna test has been validated for postmenopausal patients, few data are available regarding its use in premenopausal patients. The present study compared the Prosigna test with the Ki-67 index in premenopausal patients. Materials and Methods: Premenopausal patients with HR+ HER2−, pN0-1, G1-2 EBC were retrospectively enrolled (n = 55). The Prosigna assay was performed in formalin-fixed paraffin-embedded tumor samples of surgical resection specimens. Ki-67 was reassessed in original diagnostic core needle biopsy specimens and defined as low, intermediate, or high with the threshold of <10%, 10–24%, ≥25%. Results: According to Ki-67, patients were in the low (LR)-, intermediate (IR)-, and high-risk (HR) groups in 40%, 36%, and 24% of the cases. The Prosigna gene signature assay assessed the risk of recurrence as LR for 45% of the patients, IR for 35%, and HR for 20%. The most frequent intrinsic subtypes were luminal A in 73% and luminal B in 24% of the patients. A moderate correlation was found between Prosigna and Ki-67 scores with a Pearson correlation coefficient of 0.51. In the overall cohort, 47% of the Ki-67-based therapy decision would correspond to those based on the Prosigna score. After exclusion of IR patients, matching of low/low or high/high results was observed in 57% of the cases. Conclusion: According to the present study, there is only limited concordance regarding the risk group stratification between Ki-67 and Prosigna-based risk assessment. The relevance and frequency of premenopausal breast cancer emphasizes the need for further evaluation of gene expression analyses in this setting and the correlation with classic clinicopathological parameters regarding therapy decision-making.

Abstract P5-02-09: Quantitative analysis of fiber-level collagen features in H&amp;E whole-slide images predicts neoadjuvant therapy response in patients with HER2+ breast cancer

Abstract Background: Neoadjuvant treatment (NAT) combining chemotherapy and HER2-targeted agents is frequently administered to HER2-positive (HER2+) breast cancer (BC) patients, with some experiencing a pathological complete response (pCR) and others having residual disease measured by the residual cancer burden (RCB) score. Here, we use a physics-guided machine learning (ML)-based approach to extract fiber-level collagen features from hematoxylin and eosin (H&amp;E)-stained whole slide images (WSIs) and identify collagen-related associations with treatment response in HER2+ patients receiving NAT. Methods: Clinical data and specimens from stage II-III HER2+ BC patients enrolled on the De-escalation to Adjuvant Antibodies Post-pCR to Neoadjuvant THP (DAPHNe; NCT03716180) clinical trial and treated with neoadjuvant paclitaxel/trastuzumab/pertuzumab were analyzed. An ML-based model trained to identify regions of BC tissue as invasive carcinoma, ductal carcinoma in situ (DCIS), diffuse inflammatory infiltrate, stroma, necrosis, or normal tissue was deployed on WSIs of H&amp;E-stained diagnostic core needle biopsies (N=89) to generate tissue overlays. Additional tissue areas were computed from the tissue model predictions using heatmap transformation, including tumor nests (continuous regions predicted as invasive cancer epithelium or DCIS), tumor nest borders (stromal region boundaries 10 μm from tumor nests), and bulk tumor borders (stromal region boundaries 300 μm from aggregated tumor nests). A separate ML-based model trained to identify fiber-level collagen features in WSIs of H&amp;E-stained specimens was also deployed to generate collagen overlays. A fiber feature extraction pipeline was utilized to characterize properties of all identified collagen fibers in the WSI (on the order of hundreds of thousands per slide), including length, width, tortuosity, and angle. These fiber features were then assessed based on their position within the tumor (e.g. relative to the tumor nest border). Combinatorial features (e.g. angle of fibers with respect to tumor boundary) were then explored univariately for associations (N=609) with treatment response. Patients with pCR (RCB=0; N=53) were considered responders, while all other cases (RCBI-III; N=36) were designated non-responders. Due to the small size of the cohort analyzed here, raw p-values are reported. Results: Using estrogen receptor status as a clinical covariate, a logistic regression-based univariate analysis of 609 collagen-associated features revealed six features to strongly associate with pCR (p&amp;lt; 0.05, AUC≥0.75; Table 1). Notable feature themes were identified: 1) fiber tortuosity in tumor nest borders and tumor borders, 2) angle of fibers in tumor border with respect to tumor boundary, and 3) distribution patterns of fiber width in tumor nest borders. The presence of fibers perpendicular to tumor boundary tangents was negatively associated with pCR, as was higher fiber tortuosity and thickness in tumor nest borders. Conclusions: Improved prediction of response to NAT in patients with BC is needed to determine appropriate treatment strategies for each patient. Here, using ML-based models to identify tissue features and collagen fibers, we identify collagen-associated features, measured directly from WSIs of H&amp;E-stained diagnostic BC biopsies, that negatively correlate with pCR. Additional development of this strategy, including the addition of cell identification models and known clinical information, is underway to further refine this novel predictive model. Citation Format: Tan H. Nguyen, Mohammad Mirzadeh, Aaditya Prakash, Emma L. Krause, Jun Zhang, Michael Pyle, Esther R. Ogayo, Harry C. Cramer, Busem Binboga Kurt, Jacqueline Brosnan-Cashman, Michael G. Drage, Stuart Schnitt, Andrew H. Beck, Michael Montalto, Ilan Wapinski, Laura Chambre, Sara Tolaney, Adrienne Waks, Justin Lee, Elizabeth A. Mittendorf. Quantitative analysis of fiber-level collagen features in H&amp;E whole-slide images predicts neoadjuvant therapy response in patients with HER2+ breast cancer [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 P5-02-09.

Abstract P1-05-02: Reducing Delays of Breast Cancer Care Using An Innovative Digital Health Platform

Abstract Background: For breast cancer patients, prolonged time from core needle biopsy to initiation of treatment is associated with an incremental decrease in overall survival. This overall survival reduction disproportionately affects patients with stage I and II breast cancer (hazard ratio: 1.09-1.16, p&amp;lt; 0.001), the subgroup of breast cancer patients for which a survival reduction would be least expected due to its early stage and least accepted due to its large population size and potential increased cost of healthcare. Materials and Methods: We conducted an IRB-approved quality improvement initiative among patients with Medicare Advantage at a large integrated healthcare organization in Nevada to assess the ability of an innovative digital health platform to reduce the time interval between positive core needle biopsy to initiation of breast cancer treatment compared to a historical cohort of Medicare Advantage patients diagnosed and treated at the same facility over the preceding 6-month period. The study was restricted to women evaluated at a single contracted breast imaging center for inconclusive (Bi-RADS 0) and suspicious (BI-RADS 4 &amp; 5) mammograms, ultrasound, and/or breast MRI. Time to treatment (TTT) calculations were limited to the subset of patients diagnosed with in situ and invasive breast cancer by core needle biopsy. The primary goal was to reduce the historical TTT by greater than 50%. A secondary goal was to reduce TTT to &amp;lt; 30 days, well below the interval where overall survival would be adversely affected. Results: Between September 2021 and April 2022, 552 patients with BI-RADS 0, 4, and 5 breast imaging were enrolled in the quality improvement initiative and managed on the XpediteMD digital health platform. 208 patients were designated as BI-RADS 4 or 5 (i.e., suspicious imaging findings), all of whom ultimately underwent a diagnostic core needle biopsy. Of these, 75 patients were found to have invasive or in situ breast cancer and were subsequently referred to surgery or medical oncology where treatment was initiated. Among these patients, average TTT was 32 days with use of the digital health platform compared to 74 days in the historical cohort, a statistically significant 57% reduction in TTT, exceeding the 50% TTT goal. Although the study did not meet the target goal of average TTT &amp;lt; 30 days from needle biopsy to initiation of treatment, failure to achieve this goal was largely attributable to 3 patients who elected to delay cancer therapy for personal or health reasons. Excluding these 3 patients would have yielded an average TTT of 28.75 days, which is within our &amp;lt; 30-day goal. Conclusions: This quality improvement initiative demonstrated the successful deployment of a novel digital health platform which achieved a 57% reduction in the time interval from a positive core needle biopsy to performance of breast cancer surgery or initiation of systemic therapy. By reducing TTT to 32 days, the initiative eliminated any delay in initiation of cancer therapy that could have compromised patients’ overall survival. Citation Format: Dennis R. Holmes, Riya Pulicharam. Reducing Delays of Breast Cancer Care Using An Innovative Digital Health Platform [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 P1-05-02.

87 (PB-087) Poster - The role of axillary staging in patients with Ductal Carcinoma In Situ (DCIS) on diagnostic tissue biopsy

Background: There is an inherent risk of overestimating the risk of coexisting invasive disease in patients with DCIS on a diagnostic core needle biopsy. This results in a potential escalation of surgical intervention with the introduction of a diagnostic SLNB for the synchronous staging of the axilla which may result in additional morbidity. Patients with pure low-grade DCIS (LG DCIS) do not benefit from SLNB at the time of their primary surgery as the incidence of upgrade to microinvasion/ invasion is very low.

A Novel Risk Score (P-score) Based on a Three-Gene Signature, for Estimating the Risk of Prostate Cancer-Specific Mortality.

PurposeTo develop and validate a risk score (P-score) algorithm which includes previously described three-gene signature and clinicopathological parameters to predict the risk of death from prostate cancer (PCa) in a retrospective cohort.Patients and MethodsA total of 591 PCa patients diagnosed between 2003 and 2008 in Stockholm, Sweden, with a median clinical follow-up time of 7.6 years (1–11 years) were included in this study. Expression of a three-gene signature (IGFBP3, F3, VGLL3) was measured in formalin-fixed paraffin-embedded material from diagnostic core needle biopsies (CNB) of these patients. A point-based scoring system based on a Fine-Gray competing risk model was used to establish the P-score based on the three-gene signature combined with PSA value, Gleason score and tumor stage at diagnosis. The endpoint was PCa-specific mortality, while other causes of death were treated as a competing risk. Out of the 591 patients, 315 patients (estimation cohort) were selected to develop the P-score. The P-score was subsequently validated in an independent validation cohort of 276 patients.ResultsThe P-score was established ranging from the integers 0 to 15. Each one-unit increase was associated with a hazard ratio of 1.39 (95% confidence interval: 1.27–1.51, p < 0.001). The P-score was validated and performed better in predicting PCa-specific mortality than both D’Amico (0.76 vs 0.70) and NCCN (0.76 vs 0.71) by using the concordance index for competing risk. Similar improvement patterns are shown by time-dependent area under the curve. As demonstrated by cumulative incidence function, both P-score and gene signature stratified PCa patients into significantly different risk groups.ConclusionWe developed the P-score, a risk stratification system for newly diagnosed PCa patients by integrating a three-gene signature measured in CNB tissue. The P-score could provide valuable decision support to distinguish PCa patients with favorable and unfavorable outcomes and hence improve treatment decisions.

Abstract P2-08-11: How reliable are biomarkers assessed on a core needle biopsy? A study of paired core needle biopsies and surgical specimens in early breast cancer

Abstract Background: The conventional biomarkers estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), Ki67, and Nottingham histologic grade (NHG) are used to classify breast cancer into its molecular subtypes, determine prognosis, and guide treatment. A preoperative core needle biopsy (CNB) is used to confirm the diagnosis and invasiveness of a breast lesion and forms the basis for characterizing the tumor in the case of neoadjuvant primary treatment, emphasizing the importance of obtaining reliable biomarker assessment from a diagnostic CNB. Aim: The aim of this study was to determine the similarity between biomarker status assessed on a CNB compared to a medically untreated surgical specimen. Methods: Paired CNB and surgical specimens from 267 patients that were part of the prospective Sweden Cancerome Analysis Network- Breast (SCAN-B) cohort were studied. The concordance for the five biomarkers: ER, PgR, Ki67, HER2 and molecular subtype, between paired CNB and surgical specimen were investigated using immunohistochemistry (IHC) and gene expression-based analytical methods (GEX). IHC data were collected from patient medical records and gene expression was measured by RNA sequencing. Cohen’s kappa and Mcnemar’s test were used to compare the concordance of biomarkers.Results: Moderate to very good levels of concordance were observed between the biomarker status obtained on a CNB compared with the paired surgical specimen for IHC (κappa range 0.474-0.917) and GEX (κappa range 0.528-0.776), respectively. However, a significant drift from low to high Ki67 status and from negative to positive HER2 status between the CNB and surgical specimen was observed when using IHC and GEX, respectively (McNemar p &amp;lt; 0.05 for both comparisons). Moderate to good concordance levels of biomarker status were generally obtained when comparing GEX and IHC status measured from the same type of sample (κappa range 0.484-0.649) except for Ki67 which consistently displayed poor concordance levels between IHC and GEX for both CNB and surgical specimen comparisons (κappa range 0.158-0.198). Notably, a significant shift from positive to negative ER status and high to low Ki67 status was observed when comparing IHC with GEX classification (McNemar p &amp;lt;0.001 for both comparisons). Conclusion: The tissue sampling and the method of biomarker analysis may affect the results of biomarker status and ultimately affect treatment decisions. The implications of using a preoperative CNB to determine biomarker status, prognosis, and treatment choice should be taken into consideration in neoadjuvant treatment settings. Citation Format: Hani Saghir, Srinivas Veerla, Martin Malmberg, Lisa Rydén, Anna Ehinger, Lao Saal, Johan Vallon-Christersson, Åke Borg, Cecilia Hegardt, Ingrid Hedenfalk, Susanne Dieroff-Hay, Christer Larsson, Niklas Loman, Siker Kimbung. How reliable are biomarkers assessed on a core needle biopsy? A study of paired core needle biopsies and surgical specimens in early breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-08-11.

Abstract P4-07-11: Prognostic significance of changes in tumor infiltrating lymphocytes and neutrophil-to-lymphocyte ratio after neoadjuvant chemotherapy in early breast cancer patients

Abstract Introduction. There are still 30-40% of patients with early breast cancer (BC) that relapse after neoadjuvant chemotherapy (NAC). New prognostic biomarkers are needed. Current evidence shows that both markers of antitumor local and systemic immune response, such as tumor infiltrating lymphocytes (TIL) and neutrophil-to-lymphocyte ratio (NLR) have prognostic value in early BC. Most works have evaluated baseline levels, but their variation after NAC might be related to treatment resistance and should be explored.The aim of this study was to simultaneously investigate the prognostic significance of the pre-post-NAC variation of TIL and NLR in patients with early BC.Methods. Retrospective, single-center cohort of 121 patients with early BC treated with NAC between 2001 and 2010. Pre- and post-NAC TIL (CD3+) were assessed by tumor tissue microarrays performed in both diagnostic core-needle biopsy and surgical excision specimens, respectively. Pre- and post-NAC NLR were calculated based on blood tests collected within 1 month of cancer diagnosis and at the moment of surgery, respectively. The change on TIL and NLR after NAC was estimated by calculating the absolute difference of post- and pre- values of these parameters (Δpost-pre). We examined the association between the absolute difference of TIL and NLR (both divided into deciles) and survival outcomes by Cox regression. To represent in Kaplan-Meier curves the combined effect of the change of TIL and NLR in OS, we divided patients into 4 groups, depending on the sign of Δpost-pre values of TIL and NLR: 1) no TIL nor NLR increment after NAC (ΔTIL &amp; ΔNRLpost-pre≤0); 2) no TIL but NLR increment (ΔTILpost-pre≤0, ΔNRLpost-pre&amp;gt;0); 3) TIL but no NLR increment (ΔTILpost-pre&amp;gt;0, ΔNRLpost-pre≤0); and 4) TIL and NLR increment following NAC (ΔTIL &amp; ΔNRLpost-pre&amp;gt;0).Results. 47 (40%) out of 121 patients had pre- and post-NAC values of both NLR and TIL. Patients’ baseline characteristics are shown in Table 1. The median follow-up of this group was 11.5 years (IQR: 10.5 - 12.5 years). At the final follow-up date, overall survival (OS) was 87.2 %. In the univariable analysis, the increase in TIL and NLR after NAC among deciles showed a negative prognostic value for OS (TIL: HR 1.54, 95%CI 1.05-2.26, p=0.026; HR 1.32 95%CI 0.98-1.79, p=0.070). In the multivariable analysis, adjusted by cancer staging after NAC, both the increase of TIL and NLR after NAC among deciles add independent predictive value (TIL: HR 1.53, 95%CI 1.00-2.34, p=0.049; RNL: HR 1.42 95%CI 0.95-2.12, p=0.09).The subpopulation of patients with no TIL increment after NAC (Groups 1&amp;2, N=23) showed the best prognosis, with no deaths at 10 years. Among patients with TIL increment (Groups 3&amp;4, N=22), those with no NLR increment (Group 3, N=5) showed an intermediate prognosis (20% deaths at 10 years), whereas patients with concurrent NLR increment (Group 4, N=17) had the lowest OS (29.4% deaths at 10 years). Differences observed between groups were statistically significant (Log Rank p=0.042).Conclusion. The integrated characterization of TIL and NLR variations after NAC identifies different prognostic subgroups in early BC patients. In our cohort, both the increment of TIL and/or NLR after NAC are associated to a worse prognosis. Future validation of these findings in large, multicenter cohorts might allow treatment optimization by means of new strategies such as immunotherapy. Table 1.Patients’ baseline characteristicsN=47Age (median, range)56 (21, 78)Menstrual statusPostmenopausal25 (53,2%)Premenopausal22 (46,8%)Histologic subtypeInvasive ductal carcinoma42 (91,5%)Other subtypes4 (8,5%)Histologic gradeGrade 12 (4,3%)Grade 218 (38,3%)Grade 323 (48,9%)Unknown4 (8,6%)cTcT221 (44,7%)cT324 (51,1%)cT4a-d2 (4,2%)cNcN018 (38,3%)cN114 (29,8%)cN26 (12,8%)cN39 (19,1%)Molecular subtypeHR+ HER2-22 (46,8%)HER2+ HR+8 (17,0%)HER2+ HR-6 (12,8%)Triple negative10 (21,3%)Breast surgeryConservative26 (55,3%)Mastectomy21 (44,7%)Axillary surgerySentinel lymph node biopsy12 (25,5%)Axillary lymph node dissection35 (74,5%)Relapse typeMetastasis7 (14,9%)Local/contralateral1 (0,83%)Deaths6 (12,8%) Citation Format: Esmeralda Garcia-Torralba, Beatriz Álvarez-Abril, Carlos Bravo-Pérez, Esther Navarro Manzano, Pilar de la Morena Barrio, Alejandra Ivars Rubio, Elisa García-Garre, Gema Marín Zafra, Francisco Ayala de la Peña, Elena García-Martínez. Prognostic significance of changes in tumor infiltrating lymphocytes and neutrophil-to-lymphocyte ratio after neoadjuvant chemotherapy in early breast cancer patients [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-07-11.

Abstract P1-08-26: Morphologic characterization of tumor-infiltrating lymphocytes and its relation with pathological response in a series of breast cancer patients treated with primary chemotherapy

Abstract Introduction: Tumor-Infiltrating Lymphocytes (TILS) is a well-known predictor of response to primary chemotherapy1,2 and a prognostic factor for improved survival in different breast cancer subtypes3. We present data on the association of the level of TILs and morphologic characteristics of such infiltrate with pCR. Material and methods: A series of 477 breast cancer patients (479 tumors) treated with primary chemotherapy at Catalan Institut of Oncolgy - H.U. Bellvitge between January 2009 and December 2016. Chemotherapy consisted on anthracyclines and taxanes (plus trastuzumab if Her-2 positive disease). Levels of percentage of TILs using hematoxylin-eosin-stained sections of diagnostic core-needle biopsy were evaluated according to international guidelines in a prospectively defined retrospective analysis. Characterization of TILS consisted on identification of plasma cells, intraepithelial infiltrate vs stromal infiltrate and homogeneous vs heterogeneous infiltrate. A sub-classification using levels of TILS and heterogeneity was done for statistical purposes. Levels of TILS and their morphological characteristics were examined for their associations with pCR adjusted for predictive clinic-pathological factors, by univariate and multivariate logistic regression, statistical significance set at 0.05. A ROC curve was performed to look for a cut-point of TILs to predict PCR. Results: The mean value of TILs was 23.79% (SD, 24%). TILs were significantly higher in ductal carcinomas (39.1% vs 0%, p=0.007), grade 3 (55.2 vs 17.7%p&amp;lt;0.001), ki 67 &amp;gt;30 (48.8% vs 24.5%, p&amp;lt;0.001), HER2 (56.6%) and triple negative tumors (TNBC)(56.6%) vs luminal (20%), p&amp;lt;0.001). The level of TILS was set in 20% to predict pCR by a ROC curve (S=62.3% E=71%). Characterization of TILs found plasma cells in 41.1% of the samples, intraepithelial infiltrate in 11.2% and homogeneous infiltrate in 60.1%. Homogeneously high infiltrate was found in 20% of the samples. In the univariate analysis pCR was higher in samples with TILs &amp;gt; 20% (15.2% vs 41.5%, OR: 3.96 [95%CI, 2.57-6.10]; P &amp;lt; 0.001); plasma cells (OR 6.61 [95%CI, 1.51-28.8]; P=0.01), intraepithelial TILS (OR: 10.34 [95%CI, 2.22-48.01]; P =0.003), homogeneous high infiltrate (OR: 13.6 [95%CI, 3.04-60.77]; P =0.001). In luminal tumors, TILs over 20% predicted pCR (OR 12.3 [95%CI, 4.0-37.7]; P &amp;lt; 0.001) as well as in TNBC (OR 4.32 [95%CI, 1.77-10.53]; P=0 .001) but not in those cases with HER2 positive tumors (luminalB HER2 + HER2) (OR 1.65 [95%CI, 0.88-3.07]; P=0.118). In the multivariate analyses, levels of TILs &amp;gt; 20% were associated with higher pCR rates (adjusted odds ratio, 2.44 [95%CI, 1.48-4.01]; P &amp;lt; .001). Conclusions: The presence of TILs over 20% at diagnosis is an independent, positive, predictive marker of pCR in early breast cancer treated with neoadjuvant chemotherapy. Interestingly, the predictive information added by TILs &amp;gt;20% was higher in luminal and triple negative tumors compared to HER2 positive cases. Careful morphological characterization of TILS may add valuable predictive information and can be done in current pathologic laboratories with a well-trained breast cancer pathologist.

Discordance of Histological Grade between Diagnostic Core-Needle Biopsy and Resection Specimen for Retroperitoneal Leiomyosarcomas

Background: Diagnostic core-needle biopsy (DCNB) allows to identify the histological subtype of soft-tissue sarcoma in retroperitoneal sarcomas (RPS) with reasonable accuracy and safety. This allows for treatment tailored to different histologic subtypes of RPS, including neoadjuvant therapy. The discrepancy between the histological grade between DCNB and the resection specimen for retroperitoneal Leiomyosarcomas (RPLMS) has been highlighted before. The histological grade on DCNB is an important tool to select patients for preoperative therapy.

Abstract PS5-31: Molecular markers of response to s-equol, a novel oral estrogen receptor (ER) beta agonist for triple negative breast cancer

Abstract Introduction: Patients with TNBC breast cancer have inferior treatment outcomes compared to other breast cancer subtypes and targeted therapies are lacking. S-equol is a novel oral Estrogen Receptor (ER) Beta agonist with preclinical data showing suppression of TNBC cellular proliferation, and recently presented data showed a decrease in Ki-67 in patients treated with S-equol. This abstract will present the molecular markers that correlate with Ki-67 change in patients with TNBC treated with neoadjuvant S-equol. Methods: We conducted a neoadjuvant window trial that enrolled 39 patients with confirmed TNBC on diagnostic core needle biopsy. Cohort A (20 patients) received a daily dose of 50 mg PO twice daily and Cohort B (19 patients) received a higher dose of 150 mg twice daily. Paired biopsies were evaluable for 36 patients. Both cohorts were treated for a duration of 10-21 days. Primary outcome was change from pre- to post-treatment Ki-67 evaluated by paired t-test and that data was previously published. Secondary endpoints include: Tumor infiltrating lymphocytes in intratumoral and peritumoral (stromal) locations using CD3 (pan T cell) and CD8 (cytotoxic T cell) immunohistochemistry, density of lymphocytes per high power field (40x) for both locations in pre-treatment and post-treatment specimens, Cyclin-D1 protein expression in pre-treatment and post-treatment biopsies as percentage of total tumor cells in pre-treatment and post-treatment specimens, and total estrogen receptor-beta protein expression using immunohistochemistry qualitatively and quantitatively using All-red score in pre-treatment and post-treatment specimens.Results: The primary outcome of Ki-67 decrease of at least 20% from baseline was observed in 28% of the patients. This is a placeholder abstract and an updated abstract with the correlative molecular markers as outlined above will be provided. Conclusion: S-equol is a novel well tolerated oral ER-Beta agonist with inhibition of proliferation in patients with TNBC as measured by a decrease in Ki-67. RNA-seq data, also previously presented, supports potential immune activation during this short period of drug exposure. Future studies aim to evaluate S-equol as an immune activating agent for combination with immunotherapies such as checkpoint inhibitors in TNBC. The pending molecular predictors of response will inform future therapeutic clinical trials for this novel therapy. Citation Format: Kate Lathrop, Virginia Kaklamani, Andrew Brenner, Rong Li, Alia Nazarullah, Sarah Hackman, Courtney Thomas, Jonathan Gelfond, Marisa Rodriguez, Richard Elledge. Molecular markers of response to s-equol, a novel oral estrogen receptor (ER) beta agonist for triple negative breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS5-31.

Abstract PS11-35: Mipra, a window of opportunity study evaluating mifepristone treatment for postmenopausal breast cancer patients with higher levels of progesterone receptor isoform a than b

Abstract Background: Different antiprogestins have been clinically evaluated in gynecological andbreast cancers. Mifepristone (MFP), as well as onapristone and telapristone acetate, showedpartial responses in breast cancer clinical trials. Preclinical data indicates that antiprogestinsinhibit cell proliferation of luminal breast carcinomas expressing higher levels of progesteronereceptor isoform A (PRA) than those of isoform B (PRB) evaluated by western blots (WB). Thus,we designed a pre-surgical window trial to determine the therapeutic effects of oral MFP oncell proliferation and on differential gene expression in 20 breast cancer patients selected bytheir high PRA/PRB isoform ratio.Methods. MIPRA is an open-label, one-arm, prospective interventional study (NCT02651844).We interviewed 140 naive breast cancer patients and 133 accepted to participate. Four coreultrasound-guided biopsies were performed, two were formalin-fixed for diagnosis, ER, PR,HER2, and Ki67 evaluation and two were snap-frozen for WB and molecular studies. Patientsthat met the inclusion criteria, with ER+, PRA/PRB&amp;gt;1.5 and total PR ≥50% determined by WBand immunohistochemistry (IHC), respectively, were included for MFP treatment. Plasma wasobtained before and after treatment for future studies. Patients were treated with oral MFP(200 mg/day) for 14 days before surgery which was performed on day 15. Clinical examinationwas performed at days 7 and 14 to register possible adverse effects and to measure tumorsize. During surgery, samples were formalin-fixed for IHC studies, and others were snap-frozenfor further molecular studies. One patient had a bilateral breast cancer, and both tumorsmatched with the inclusion criteria and were included. The primary endpoint was Ki67labeling, comparing diagnostic core needle biopsy to post-therapy surgical specimens.Considering previous studies performed with tamoxifen, we pre-specified that 30% of relativereduction in Ki67 would be considered as a positive response. Differences in Ki67 expressionwere quantitated by an expert pathologist counting at least ten 40x fields per slide. Theseresults are currently being validated by a second pathologist. One patient, with a core biopsywith less than 500 total cells, was excluded. Ongoing experiments include secondary and otherendpoints: comparison of apoptotic, proliferative and hormone receptor markers by IHC,measurement of MFP plasma levels and, RNAseq analysis in samples pre- and post-treatment. Ki67 changes from baseline were tested with paired Wilcoxon matched-pairssigned-rank test.Results: The median (range) Ki67 value of biopsies was 11.87% (2.70- 34.56) and for surgicalspecimens was 6.45% (0.48-23.77). A 45.67% of decrease in the median % Ki67 (41.63%comparing the arithmetic mean values and 50.83% comparing the geometric mean values) wasregistered in all surgical specimens compared to baseline (p= 0.003). Using the pre-specifiedresponse parameter (30% relative reduction in Ki67), we identified 15/20 (75%) responders.Considering only responsive tumors, a 49.87% decrease in the median % Ki67 (50.83%,arithmetic mean; 62.34% geometric mean) was observed (p&amp;lt;0.0001) between baseline andsurgical specimens. In those cases with the highest response, the decrease in Ki-67 wasaccompanied by a decrease in tumor volume (ultrasound measurements).Conclusion: Our results show that MFP treatment may be effective in patients showing a highPRA/PRB ratio. The magnitude of the inhibition was similar or higher to that reported fortamoxifen in ER+ breast cancer patients in short-term treatment studies. Ongoing analysis willdetermine if there are changes in other markers that may help to further define MFP-responsive patients. Citation Format: Andres Elia, Silvia I Vanzulli, Hugo Gass, Caroline A Lamb, Victoria T Fabris, Paula Martinez Vazquez, Javier Burruchaga, Eunice Spengler, Ines Caillet Bois, Alejandra Castets, Silvia Lovisi, Marcos Liguori, Gabriela Pataccini, M Florencia Abascal, Virginia Novaro, Gabriela Acosta Haab, Alfredo Molinolo, Paola Rojas, Claudia Lanari. Mipra, a window of opportunity study evaluating mifepristone treatment for postmenopausal breast cancer patients with higher levels of progesterone receptor isoform a than b [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS11-35.

Encysted Papillary Carcinoma of the Breast (EPC): A Follow-up Study to Investigate the Role of Sentinel Lymph Node Biopsy

Background: Encysted papillary carcinoma (EPC) is a rare breast neoplasm that mainly affects postmenopausal women. The purpose of this study was to examine whether a sentinel node biopsy would be deemed necessary in patients with a diagnosis of EPC and to determine if evidence of invasiveness can be diagnosed on a core needle biopsy with sufficient confidence to guide decision making for upfront axillary SLNB.Methods: The available data of patients with EPC of the breast were reviewed at a tertiary breast cancer unit over a period of 10 years (2009-2019) and the concordance between core needle biopsy and final histology was assessed. We also carried out a detailed review of the available literature to inform best practice guidance for management of the axilla. Results: During the study, a total of 37 EPC patients were identified, of whom 10 were excluded as they declined further treatment, providing us a study sample of 27 patients. The median age at diagnosis was 72 years (range 47-97) and the vast majority of patients (96%) were Estrogen Receptor (ER) positive. Of the 27 patients treated, 17 (63%) underwent a diagnostic axillary Sentinel Lymph Node Biopsy (SLNB). On the final histology, 13/27 (48%) proved to have invasive disease. A total of 5 (18%) patients had evidence of metastasis in the axillary nodes, of whom only 7% had macro-metastatic disease that warranted further axillary treatment. None of the treated patients had evidence of recurrence or distant metastatic disease, to date (median of 5 years of follow up).Conclusions: Encysted papillary carcinoma is associated with a low incidence of axillary node involvement. SLNB should only be carried out when there is evidence of invasive cancer. An algorithm was developed to help guide management of the axilla in cases diagnosed with EPC on diagnostic core needle biopsy.

Upgrade at excisional biopsy after a core needle biopsy diagnosis of classic lobular carcinoma in situ

BackgroundManagement of patients with classic lobular carcinoma in situ diagnosed on core needle biopsy remains controversial, in part because of clinicopathologic overlap with atypical lobular hyperplasia. Although atypical lobular hyperplasia on core needle biopsy is observed because of its low upgrade rate (~1%), consensus is lacking for lobular carcinoma in situ. Therefore, we evaluated lobular carcinoma in situ upgrade rates. MethodsWith institutional review board approval, we identified 90 patients (from October 2008 to December 2019) with lobular carcinoma in situ on core needle biopsy as their highest-risk lesion. We excluded patients with concurrent ipsilateral cancer. Variables associated with upgrade were assessed with logistic regression. ResultsOf the 90 patients, 81 (90%), median age 55 y, underwent surgical excision. Indications for diagnostic core needle biopsy included mammographic calcifications (48, 53.3%), mass/distortion (28, 31.1%), and non-mass enhancement (12, 13.3%). Final surgical pathology upgraded 11 of 81 patients (13.6%, 95% CI: 7.8%–22.7%) to cancer: invasive lobular (n = 7), invasive ductal (n = 1), and ductal carcinoma in situ/pleomorphic lobular carcinoma in situ (n = 3). Only 1 patient with invasive cancer was node-positive. Concurrent contralateral cancer (OR 4.41, 95% CI: 1.06–17.38, P = .04) and larger lesion size (OR 1.78 per 1 cm, 95% CI: 1.19–2.95, P = .005) predicted upgrade. ConclusionOur data suggest that, unlike atypical lobular hyperplasia, lobular carcinoma in situ identified on core needle biopsy should be surgically excised. The high proportion of upgrades to early stage invasive lobular carcinoma underscores the value of this approach.

Novel estrogen receptor beta agonist S-equol decreases tumor proliferation in patients with triple negative breast cancer (TNBC).

560 Background: Patients with TNBC breast cancer have inferior treatment outcomes compared to other breast cancer subtypes and targeted therapies are lacking. S-equol is a novel oral Estrogen Receptor (ER) Beta agonist with preclinical data showing suppression of TNBC cellular proliferation. We therefore conducted an early phase window of opportunity trial to evaluate the impact of S-equol on Ki-67 change in patients with TNBC. Methods: This neoadjuvant window trial enrolled 39 patients with confirmed TNBC on diagnostic core needle biopsy. Cohort A (20 patients) received a daily dose of 50 mg daily and Cohort B (19 patients) received a higher dose of 150 mg daily. Paired biopsies were evaluable for 36 patients. Both cohorts were treated for a duration of 10-21 days. Primary outcome was change from pre- to post-treatment Ki-67 evaluated by paired t-test. All tests were 2-sided with a significance level of 0.05. Statistics were conducted within an accountable data analysis process in R (ADAPR). Secondary outcomes included toxicity and correlative biomarkers. Results: The mean (SD) pre-treatment was 68% (21.99) and post-treatment 59% (20.62). The average decrease in Ki-67 was 8% (P = 0.00206, 95% CI -13.46 to -3.26). A Ki-67 decrease of at least 20% from baseline was observed in 28% of the patients. S-equol was well tolerated with the most common toxicities being nausea, constipation, diarrhea, and headache. All toxicities were grade one. Treatment compliance was greater than 95%. Planned correlative studies included RNA-seq. A total of 161 genes are differentially expressed with fold change &gt; = 2 and p value &lt; 0.05. The top genes of the differential expression list include BMP5, S100A7, FABP7, SCGB2A2, CH507-338C24.1, and DUSP1. Gene Set Enrichment Analysis (GSEA) indicates that top enriched gene modules are related to interferon function and immune response, most of which are downregulated in the post-treatment group. Conclusions: S-equol is a novel well tolerated oral ER-Beta agonist with inhibition of proliferation in patients with TNBC as measured by a decrease in Ki-67. RNA-seq data supports potential immune activation during this short period of drug exposure. Future studies aim to evaluate S-equol as an immune activating agent for combination with immunotherapies such as checkpoint inhibitors in TNBC. Clinical trial information: NCT02352025 .

Abstract OT1-01-03: Impact of RANKL inhibition on tumor microenvironment of early-stage breast cancer, a pre-surgical trial

Abstract BACKGROUND: Receptor activator of NF-kB (RANK) and its ligand (RANKL) have a well-established role in osteoclast-driven bone remodeling, however RANK/RANKL expression can also be seen on mammary epithelial cells and immune cells (IC). In breast cancer (BC) mouse models, RANKL is a paracrine effector of the mitogenic activity of progesterone and inhibition of RANKL can attenuate development of BC as well as the incidence of metastases. Pre-clinical evidence demonstrates that RANKL exerts effects on IC such as regulatory T cells (Tregs) and tumor associated macrophages (TAMs) within the tumor microenvironment (TME), thereby promoting tumor progression and metastases. Clinical studies also support a deleterious role for these IC subsets specifically in breast cancer, with high density of either Tregs or TAMs associated with increased risk for distant recurrence. Despite this preclinical support for targeting the RANK/RANKL pathway, clinical trials in early stage BC have had discordant results regarding the clinical benefit of denosumab (RANKL antagonist). As such, it is of significant clinical relevance to identify a drug response signature following treatment as this may suggest biomarkers predictive of benefit from adjuvant denosumab. This window-of-opportunity study was designed to evaluate the pharmacodynamic biomarkers of RANKL inhibition, as well as denosumab’s impact on the TME in paired tumor specimens from patients with BC following treatment with denosumab. Defining the immunomodulatory effects of denosumab may additionally provide biologic rationale for synergistic combination with specific immunotherapy agents. TRIAL DESIGN: This study is a single-arm open label Phase 0 (pre-surgical/window of opportunity) trial. Following diagnostic core needle biopsy, patients receive one dose of denosumab 120 mg given subcutaneously prior to surgical resection. ELIGIBILITY CRITERIA: ≥18 years of age with histologically-confirmed invasive BC &amp;gt;1 cm by radiographic or clinical criteria with available tissue from the core biopsy and planned surgery. Patients are ineligible for this study if neoadjuvant therapy is being considered. STUDY OBJECTIVES: The primary objective is to identify pharmacodynamics markers of RANKL inhibition in early BC. Planned analyses include protein and transcriptomic analyses of known targets of RANKL and compare treatment effect in both RANK/RANKL+ and RANK/RANKL- BC. As a secondary objective, the effect of RANKL inhibition on host immune response will be assessed by comparing pre-treatment biopsy specimens and surgical excision specimens from patients treated with denosumab and untreated controls matched for BC subtype and menopausal status. Planned analyses include RANK/RANKL expression on IC subsets, enumeration of tumor infiltrating lymphocytes by H&amp;E, immunophenotype by immunohistochemistry (e.g. cytotoxic T lymphocytes, Tregs, TAMs) and expression of immune related genes (nanoString Pancancer Immune Panel). STATISTICAL METHODS: As RANK/RANKL protein expression is expected in 25-30% of BC, we plan to enroll 35 subjects to ensure at least 10 subjects with RANK/RANKL+ tumors will be included in our study cohort. With 10 subjects with tumors with high RANK/RANKL expression at baseline, a change from baseline of a single gene of &amp;gt;|1.7| standard deviations between subjects with and without RANK/RANKL expression is detectable based on a 2-sided two sample t-test with power of 80% and false discovery rate of 10%. Differential gene expression analysis will be performed comparing denosumab treated patients with RANK/RANKL+ vs. RANK/RANKL- BC, and between treated patients and untreated controls. PRESENT ACCRUAL: 29 of the planned 35 patients have been enrolled to date. Citation Format: Douglas Kanter Marks, Deborah Axelrod, Maryann Kwa, Nancy Tray, Karen Hiotis, Amber Guth, Yelena Novik, James Speyer, Victor Ty, Adriana Heguy, Judith Goldberg, Farbod Darvishian, Sylvia Adams. Impact of RANKL inhibition on tumor microenvironment of early-stage breast cancer, a pre-surgical trial [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT1-01-03.

Abstract P1-10-15: BRCA1 alterations with additional defects in DNA damage repair genes may confer chemoresistance to BRCA-like breast cancers treated with neoadjuvant chemotherapy

Abstract The BRCA-like phenotype is a feature that some sporadic breast cancers share with those occurring in germinal BRCA1- or BRCA2-mutation carriers. Since tumors with the phenotype have defects in the DNA damage repair pathway, which may increase sensitivity to drugs such as DNA cross-linking agents and PARP inhibitors, a method to identify this phenotype is important. The prediction of chemoresistance, which frequently develops in these tumors, is also crucial for improving therapy. We examined genomic aberrations and BRCA1 promoter methylation in tumors of 73 breast cancer (20 HR-/HER2- and 53 HR+/HER2-) patients, who underwent diagnostic core-needle biopsy and received neoadjuvant chemotherapy with anthracycline, cyclophosphamide, and taxane, using SNP array CGH and quantitative PCR. They had a tumor size of T1, T2, T3, or T4, a lymph node status of N0, N1, N2, or N3, and no distant metastasis (M0) at diagnosis, and were enrolled as subjects in this study. The methylation and/or loss or UPD of BRCA1 (termed BRCA1 alterations) and the loss or UPD of BRCA2 (termed BRCA2 alterations) were detected in 27 (37%) and 21 (29%), respectively, out of 73 tumors. Tumors with BRCA1 or BRCA2 alterations were associated with a higher number of genomic aberrations (P&amp;lt;0.001 and P&amp;lt;0.001) and higher percentage of TP53 alterations (the loss or UPD and/or mutations) than those without (P&amp;lt;0.001 and P&amp;lt;0.001). Overall survival (OS) rates were similar between patients with or without BRCA1 or BRCA2 alterations. However, when 27 patients with BRCA1-altered tumors were classified into those with or without the loss or UPD of PALB2, PAGR1, RAD51B, FANCM, MLL4 or ERCC1/2 in tumors, patients with additional defects in DNA damage repair genes had worse OS (P=0.037, 0.045, 0.038, 0.044, 0.041, or 0.019) than those without. These defects may confer chemoresistance and predict poor outcomes in patients with BRCA1-altered breast cancer. Citation Format: Mamoru Takada, Yasuhiko Kaneko, Masayuki Haruta, Shigenori Nagai, Kenichi Inoue, Katsunori Toduka, Masafumi Kurozumi, Hiroyuki Takei, Seishi Ogawa, Takeshi Nagashima, Takafumi Sangai, Hiroshi Fujimoto, Junta Sakakibara, Ryotaro Teranaka. BRCA1 alterations with additional defects in DNA damage repair genes may confer chemoresistance to BRCA-like breast cancers treated with neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-10-15.

Abstract P5-04-02: Progesterone receptor (PR) antagonism by telapristone acetate (TPA): A randomized, placebo-controlled phase IIB pre-surgical window trial in women with stage 0-II breast cancer

Abstract Background: In vitro and preclinical data indicate that TPA, a selective PR modulator, has activity against hormone-sensitive early breast cancer. We conducted a pre-surgical window trial of oral TPA in Stage 0-II breast cancer to assess the effect of TPA on suppression of cell proliferation (Ki67), and on differential gene expression in responsive and non-responsive tumors. Methods: We enrolled 70 pre and postmenopausal women into a 1:1 randomized, double-blind, placebo-controlled trial of oral TPA 12mg (Repros Therapeutics Inc.) for 2-10 weeks. The primary endpoint was Ki67 labelling, comparing diagnostic core needle biopsy to post-therapy surgical specimens. Ki67 changes were quantitated by dual immunohistochemistry (Ki67/pan-cytokeratin) and image analysis (Aperio ImageScope and Definiens Tissue Studio®). RNA-sequencing (using RNA extracted from the paraffin blocks) was performed with Illumina TruSeq RNA Coding Access method. Differential gene expression pre-post therapy was assessed, followed by Gene Set Enrichment Analysis for pathway analysis. Ki67 changes from baseline were tested with Paired signed-rank test. For gene expression analysis, p values were calculated by Wald test and adjusted for multiple comparisons by Benjamini-Hochberg method (adjusted p &amp;lt;0.05 and 2-fold gene expression cut-off). Results: Among 61 evaluable women, (29 placebo and 32 TPA) 97% of tumors were ER or PR positive and 91% were ER and PR positive (balanced across arms). A significant 6% decrease in mean %Ki67 was seen in the TPA arm (p= 0.003). When stratified by menopause, the significance held in premenopausal women (n= 22, p= 0.03) but not in postmenopausal women (n=10, p= 0.08). However, a Ki67 decrease (4%) was also observed in placebo group (p = 0.04); this was non-significant after pre- postmenopausal stratification. Overall, differential gene expression analysis showed no significant modulation of genes in either group. Using a pre-specified response parameter (50% relative reduction in Ki67), we identified 12/32 (38%) “responders” in the TPA, and 9/29 (31%) in the placebo arm. In sub-group analysis of these responders, we found 103 genes to be significantly modulated by treatment in the TPA “responders”, but saw no significant change in any gene expression in placebo “responders”. Gene set enrichment analysis for the 103 genes showed that TPA blocked the progression of cell cycle genes (PTTG1, PLK1, UBE2C, HIST1H3F, PSMD3, and etc.) and suppressed PGR and ERBB2 expression. In a pre-planned pooled analysis, these results will be combined with NCT02314156, reported in SABCS abstract 851790. Conclusions: An anti-proliferative (Ki67) signal of TPA was observed in early stage breast cancer patients, but interpretation was limited by placebo group changes. The TPA group demonstrated differential suppression of proliferation-related genes among Ki67 responders, but the placebo group did not. Ongoing analysis will examine signatures related to stemness, metastasis, and immune suppression (potentially better endpoints in trials targeting P signaling). These analyses may help us select the right population and the right biomarkers for future trials. Citation Format: Lee O, Sullivan ME, Xu Y, Shidfar A, Ivancic D, Zeng Z, Singhal H, Helenowski I, Jovanovic B, Hansen N, Bethke K, Gann P, Gradishar WJ, Clare SE, Khan SA. Progesterone receptor (PR) antagonism by telapristone acetate (TPA): A randomized, placebo-controlled phase IIB pre-surgical window trial in women with stage 0-II breast cancer [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 P5-04-02.

Abstract OT1-04-01: A phase IIB pre-surgical trial of oral tamoxifen (TAM) versus transdermal 4-hydroxytamoxifen (4-OHT) in women with DCIS of the breast

Abstract Background Ductal carcinoma in situ (DCIS) is diagnosed in 60,000 women annually in the US. TAM is proven to reduce risk of local recurrence and new primary breast cancer in women with estrogen receptor (ER) positive DCIS. However, acceptance of TAM has been low, primarily because of toxicity related to systemic exposure. Local delivery to the breast is an attractive alternative since low systemic levels could minimize toxicity. 4-OHT is an active metabolite of TAM. When formulated as a gel and applied to the breast skin, it is well tolerated, and results in 4-OHT breast tissue drug levels comparable oral TAM. In small pilot studies, its anti-proliferative effects on invasive breast tumors and DCIS are also similar to oral TAM [Lee O, et al. PMID 25028506]. The goal of our study is to validate these results in preparation for a Phase III trial of 4-OHT gel in comparison to oral TAM. Methods We are conducting a randomized, double-blinded, placebo-controlled, Phase IIB pre-surgical trial to demonstrate that daily application of 4-OHT gel will result in a reduction in the Ki-67 labeling index of DCIS lesions that is not inferior to that seen in women receiving daily oral TAM 20 mg daily. Ki-67 of the base-line diagnostic core needle biopsy will be compared to that of the therapeutic surgical excision sample after oral TAM or 4-OHT gel for 8 ± 2 weeks. Secondary endpoints include changes in Oncotype DCIS-Score, IHC markers (CD68, COX2, p16), hormone levels, coagulation markers, drug concentration in the plasma and breast tissue, the fraction of women with no residual DCIS in the surgical sample, and experienced symptoms. 100 women (assuming 20% non-evaluable samples or compliance issues) with DCIS (10% ER-positive) will be enrolled across six institutions into two intervention arms: oral TAM 20 mg daily, placebo gel and 4-OHT gel 4mg daily (2mg/breast), placebo capsule. All participants will be evaluable for toxicity from their first dose. All samples from all participants who receive drug will be evaluated and included in the primary analysis, which will be based on intent to treat principle. To date 15 of 100 participants have been enrolled across six institutions including: Northwestern University in Chicago, IL, St. Elizabeth Healthcare in Edgewood, KY, Duke University Medical Center in Durham, NC, Cleveland Clinic in Cleveland, OH, Memorial Sloan Kettering Cancer Center in New York, NY, and Mayo Clinic in Rochester, MN. Since study open, 69 potential participants have been contacted, 52 did not consent for screening, 17consented for screening, 2 are pending consent, and 15 have started study intervention. The most common reasons potential participants chose not to consent are wanting to schedule surgery as soon as possible, attitudes toward medical research, and current use of a prohibited concomitant medication such as a potent inhibitor of tamoxifen metabolism or exogenous sex steroid. Funding Source: NCI Contract # HHSN2612201200035I. Citation Format: Benante KA, Xu Y, Tull MB, Segura AJ, Alber KM, Kalinichenko K, Hou L, Jovanovic B, Perloff M, Heckman-Stoddard B, Dimond E, Khan SA. A phase IIB pre-surgical trial of oral tamoxifen (TAM) versus transdermal 4-hydroxytamoxifen (4-OHT) in women with DCIS of the breast [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 OT1-04-01.

Cutting Healthcare Costs with Hematoma-Directed Ultrasound-Guided Breast Lumpectomy.

Localization of nonpalpable breast lesions for breast-conserving surgery (BCS) remains highly variable and includes needle/wire localization (NL), radioactive seed localization, radar localization, and hematoma-directed ultrasound-guided (HUG) lumpectomy. The superiority of HUG lumpectomy over NL has been demonstrated repeatedly in terms of safety, accuracy, low positive margin rates, cosmesis, and patient satisfaction. In this study, we evaluate the cost effectiveness of HUG lumpectomy over NL for nonpalpable breast lesions. We performed a retrospective review of 569 patients who underwent lumpectomy at the University of Arkansas for Medical Sciences from May 2014 through December 2017. Lumpectomies were stratified by localization technique, i.e. NL versus HUG. A cost-savings estimate was determined for the HUG localization technique, and a total amount of dollars saved over the study period was calculated. Overall, 569 lumpectomies were performed: 501 (88.0%) via HUG and 68 (12.0%) via NL. Intraoperative ultrasound was used in 566 operations (99.5%). Of the lumpectomies performed by HUG, 190 lesions (33.4%) were visible only on mammogram or breast magnetic resonance imaging prior to diagnostic core needle biopsy (CNB). Cost estimates comparing HUG with NL demonstrated a cost savings of $497.00 per procedure, the cost of preoperative needle localization by a radiologist, and a total of $94,430.00 for the study period. In utilizing HUG lumpectomy, the initial CNB serves as the diagnostic and localization procedure, thus saving time and a painful second procedure on the day of operation. HUG lumpectomy is safe, accurate, reduces healthcare costs, and results in a better patient experience for the surgical removal of nonpalpable breast lesions.