Northfelt, Donald W.

e18518 Background: Initiatives enhancing equitable oncologic care are an increasingly emphasized priority. Our study aims to identify aspects of breast cancer (BC) care in which differences exist based on insurance coverage status. Methods: We performed a retrospective, case control study consisting of 39 Hispanic ethnicity uninsured patients (UP) with newly diagnosed BC at federally qualified health centers and 119 insured patients (IP) diagnosed at Mayo Clinic Arizona (MCA). Patients were matched 3:1 for age, stage, year of diagnosis, ER and HER2 status. Demographic information, clinical variables, and zip code level specific socioeconomic information were compared. Continuous variables were compared by Wilcoxon rank-sum test and categorical variables by chi-square test. All patients ultimately received their cancer treatment at MCA. Results: Similar treatment patterns with chemotherapy, surgery, and radiation treatment were observed between groups. Primary language was Spanish for 94% of UP and English for 97.5% of IP. The majority of UP were of Hispanic ethnicity (97.4%); IP were 83.2% non-Hispanic White, 9.2% Hispanic, 3.4% African American. Zip code level information reflected more unemployment with a median of 10.6% versus 6.9% p ˂ 0.001, percent of high school or lower (53.0 % v 23.2 %, p ˂ 0.001), and lower income for UP (33733.5 v 64728.0 p values ˂ 0.001). UP BMI was significantly higher (30.6 V 24.7, p=0.005), with presence of more co-morbidities; diabetes (28.2% v 5.0%, p ˂ 0.001), hypertension (35.9 % v 20.2%, p= 0.046), dyslipidemia (28.2% v 12.6%, p = 0.023), metabolic syndrome (p 23.7% v 8.5, p= 0.013), and tobacco use (17.9% v 2.5%, p ˂ 0.001). IP had higher alcohol use (52.9% v 5.3%, p ˂ 0.001). Genetics consultation was performed for 62.2% IP versus 35.9% UP (p=0.004), lower acceptance of oncology nutrition consultation for UP (29.4% vs 7.4%, p= 0.024) Median time from abnormal mammogram to biopsy (25.5 days vs. 14 days, p=0.056), and interval from diagnosis to treatment (62 days vs. 39 days) (p=0.001) were less favorable for UP compared to IP. Conclusions: In comparing the status of UP (primarily Hispanic, Spanish-speaking) and IP (primarily non-Hispanic White, English-speaking) with newly diagnosed BC we identified greater prevalence of co-morbidities and adverse social determinants of health in the former group. We identified access to genetic counseling services, access to oncology nutrition consultation, and timeliness of diagnostic biopsy and initiation of treatment as disparate features in the care pathway. These observations can allow development of tailored interventions to achieve greater equity in delivery of BC care.

520 Background: Systemic inflammation may contribute to cancer progression (PMC2803035), including recurrence of early breast cancer (PMC4828958). We hypothesized that inflammatory cytokines and/or chemokines may be associated with distant recurrence (DR). Methods: We performed a case:control study in women with stage II-III Her2-negative breast cancer, all of whom had surgery and adjuvant chemotherapy (doxorubicin/cyclophosphamide, then weekly paclitaxel) with/without bevacizumab, plus endocrine therapy if ER-positive (PMC6118403). Propensity score matching was used to identify approximately 250 case:control pairs (with/without DR). Serum samples obtained before adjuvant chemotherapy were analyzed using the MSD V-Plex Human Cytokine 36-Plex Kit for detection of human cytokines and chemokines involved in the Th1/Th2 pathway, chemotaxis, the Th17 pathway, angiogenesis, and immune system regulation. Conditional logistic regression analysis, with models fit via maximum likelihood, were used to estimate hazard ratios (HRs) and test for associations. Due to skewed nature of cytokines, HRs are reported on log base 2 scale. If adjusted for multiple testing including 36 markers, a p value of < 0.0014 would be required for statistical significance. Results: A total 249 matched pairs (498 patients) were identified. Covariates used for propensity score matching included age, menopausal status (post 54% vs. pre/peri 46%), ER/PR status (one/both pos 64% vs. both neg 36%) tumor size ( < = 2cm 17%, > 2-5cm 67%, > 5cm 16%) nodal status (neg 15%,1-3+ 32%, 4+ 53%), and grade (low 3%, int. 31%, high 66%). The only biomarker associated with a significantly increased DR risk when adjusted for multiple testing was the proinflammatory cytokine IL-6 (HR 1.37, 95% confidence intervals [CI] 1.15, 1.65, p = 0.0006). Others associated with a 2-sided p value < 0.05 included the chemokine MDC(macrophage-derived chemokine/CCL22) (1.90, 95% CI 1.17, 3.1, p = 0.0098), the T helper cell inflammatory cytokine IL-17A (HR 1.36, 95% CI 1.10, 1.67, p = 0.0052), and the cytokine VEGF-A (HR 1.13 for, 95% CI 1.01, 1.27, p = 0.037). There was no statistical interaction between VEGF-A and bevacizumab benefit. The median and mean value for IL-6 was 0.95 and 7.5 pg/ml (range 0.04-2761.24 pg/ml). Conclusions: This analysis provides level 1B evidence indicating that higher levels of the cytokine IL-6 at diagnosis are associated with a significantly higher DR risk in high-risk stage II-III breast cancer despite optimal adjuvant systemic therapy. This provides a foundation for confirmatory validation of IL-6 as a prognostic biomarker, and potentially as a predictive biomarker for testing therapeutic interventions targeting the IL-6/JAK/STAT3 pathway. Supported by NCI U10CA180820,180794,180821; UG1CA189859,232760,233290, 233196; Komen Foundation; Breast Cancer Research Foundation. Clinical trial information: NCT00433511.

Abstract Background: Cyclin dependent 4/6 kinase inhibitors (CDK4/6i) and endocrine therapy (ET) have improved progression-free survival (PFS) and overall survival in hormone-receptor (HR)-positive metastatic breast cancer (MBC), but progression of disease is inevitable. Serum thymidine kinase-1 (TK1) is a secreted marker of proliferation that is prognostic in patients (pts) with HR-positive, HER2-negative MBC and may be predictive of ET and CDK 4/6i response. PROMISE (NCT0281902) is a prospective study enrolling women with HR-positive MBC starting palbociclib (Pb) + letrozole (L) (1st line) or Pb + fulvestrant (2nd line). We undertook a comprehensive “omic” assessment of blood, tumor, urine and the fecal microbiome in order to identify novel genomic variants and pathways associated with an early decline in TK1 (measured after 2 months) and PFS. Additionally, patient derived xenografts/organoids were generated at baseline and progression to test new therapeutic approaches to overcome resistance to CDK4/6i and ET. We report the initial association between the baseline genomic landscape and baseline TK1 levels. Methods: FFPE tumor biopsies were obtained for DNA/RNA sequencing (TempusTM) and blood samples for TK1 (Divitum® assay, Biovica) were collected pretreatment (pre-Pb) and after 2 cycles of Pb + ET (post-Pb2). Both whole-exome (exome capture) sequencing (WES) and RNA-Seq used the Integrated DNA Technologies xGen Exome Research Panel v1.0 capture kit. TK1+ disease was defined as &gt; 200 Du/L and TK1- disease as below limit of detection up to 200 Du/L. We tested the association between genomic and transcriptomic characteristics with baseline TK1 data in pretreatment samples where both WES and RNA-seq and TK1 was available. The data were analyzed using bioinformatics pipelines for somatic and germline mutations and copy number alterations. The current analysis focuses on baseline 1st-line pre-Pb omics data in conjunction with baseline TK1 levels. The database was locked for analysis on 5/29/2020. Results: Thirty-three pts (median age: 59 yrs.) were evaluable, with paired samples for TK1 in 32. Six pts had TK1+ disease pre-Pb and post-Pb2. Twenty-two pts had TK1- disease pre-Pb and post-Pb2. Four pts had a decrease in TK1 after 2 cycles of treatment that altered the classification from TK1+ to TK1-. Both baseline RNA seq and serum TK1 (n=16) were available for 4 TK1+ and 12 TK1- pts. In this group, 476 genes were differentially regulated (398 upregulated; 78 downregulated). Pathway analysis demonstrated enrichment in complement and coagulation cascade pathway, PPAR signaling pathway, and metabolism-related pathways related to up-regulation of CYP and UGT gene families. Further testing for the association of WES data with baseline TK1+ (n=8) and TK1- (n=16) disease demonstrated somatic copy number variations on chromosomes 6, 11, 12 and 15. CDK4 copy number gains were observed in 3/8 TK1+ pts and 0/16 TK1- pts. We also observed that somatic mutations (LOH, copy number and/or SNV/INDELs) were more prevalent in the TK1+ compared to the TK1- pre-Pb group in several cancer-associated genes (FAS [p=0.06] PTEN, PIK3CB, NAB2, SOX9 and FAT1 [p=0.08], TP53, and MAP2K4 [p=0.22]). Conversely, we also noted that 6/7 pts with GATA3 mutations had TK1- disease (p=0.23). Conclusions: Using a comprehensive “omics” approach, our data suggest that a secreted biomarker of proliferation (TK1) obtained prior to initiating CDK4/6i and ET for the first line treatment of HR+ MBC is associated with established and novel genes and pathways associated with prognosis of pts receiving ET and CDK 4/6i. Analysis of on-treatment (after 2 cycles) tumor RNA seq and its association with change in TK1 as well as data from the 2nd-line cohort will be presented at the meeting. Citation Format: Ciara C O Sullivan, Krishna R Kalari, Vera J Suman, Peter T Vedell, Ann Moyer, Abraham D Eyman Casey, Jason Sinnwell, Xiaojia Tang, Kevin Thompson, Alvaro Moreno-Aspitia, Donald W Northfelt, Minetta C Liu, Tufia C Haddad, Saranya Chumsri, Prema Peethambaram, Kathryn J Ruddy, Karthik V Giridhar, Roberto A Leon-Ferre, Adrian Nordmark, Mattias Bergqvist, Brendan P McMenomy, Richard M Weinshilboum, Liewei Wang, Matthew P Goetz. Novel genomic variants and pathways associated with baseline serum thymidine kinase 1 levels in HR-positive HER2-negative MBC patients commencing palbociclib and letrozole [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 PS5-24.

Abstract Background: Contrast-enhanced mammography (CEM) is an emerging breast imaging technique utilizing iodinated contrast to highlight areas of neovascularity. The role of CEM in patients with breast implants has not yet been characterized. We report our clinical experience of CEM in patients with breast augmentation surgery to better understand the potential diagnostic utility and limitations of CEM in the setting of breast implants. Materials and Methods: A HIPPA compliant, IRB exempt single-institution review of prospective CEM cases who had “breast implants” in their report between 01/2015 and 03/2020. Medical records were reviewed to supplement database information. Results: Forty-six patients were included with a mean age of 52 years (range 33-72). Clinical indications included: high risk research screen 3 (6%), diagnostic evaluation for abnormal imaging 24 (52%), further evaluation of newly diagnosed breast cancer 12 (26%) or assessment of neoadjuvant treatment response 7 (15%). Thirty patients had malignant lesions. Histology was invasive ductal carcinoma (90%), invasive lobular carcinoma (7%), and ductal carcinoma in situ (3%). CEM identified the index cancer and extent of disease in 28/30 (93%) of malignant cases. In two patients (7%), the malignant lesion was not included in the field-of-view due to its location. One of these lesions was a far medial mass within the breast which was detected by ultrasound alone. The other false negative CEM was a palpable axillary mass negative on both mammogram (MG) and MRI but seen by ultrasound. Twenty-three (50%) underwent additional breast MRI of which 20 had an already diagnosed cancer. the findings on CEM were concordant with MR imaging for the index lesion in 19/20 (95%) cases (kappa=0.86; p &lt;0.001). Six additional lesions were found by CEM and confirmed by MRI. Of these lesions, 33% were found to be malignant and changed the surgical procedure. Four were only seen on CEM (no MRI comparison was available) and 75% were found to be malignant. One was only seen on MRI and was benign. One additional lesion was only seen as an asymmetry on MG without CEM or MRI correlate. This was benign on both the biopsy and surgical pathology. Conclusions: CEM appears to be a valuable breast imaging modality for diagnostic evaluations and surgical staging, including patients with breast implants. Due to technical artifacts and positioning limitations for posterior lesions, we recommend performing CEM with implant displaced views. Breast centers that use CEM, should be aware of field of view as a potential limitation when evaluating extent of disease in patients with breast augmentation. Citation Format: Molly Carnahan, Barbara Pockaj, Victor Pizzitola, Marina Giurescu, Roxanne Lorans, William Eversman, Richard Sharpe, Patricia Cronin, Donald Northfelt, Karen Anderson, Brenda Ernst, Bhavika Patel. Experience of contrast-enhanced mammography in patients with breast augmentation surgery [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 PS3-23.

Abstract Objective and Rationale: To investigate the utility of screening Contrast Enhanced Mammography (CEM) imaging as a supplemental screening tool in women at elevated risk for breast cancer. Materials and Methods: This prospective, single institution, IRB approved observational study was conducted in asymptomatic women 35 years of age or older who were deemed at elevated risk of breast cancer, defined as IBIS v.8.0 lifetime risk of breast cancer score &gt;15% or a prior personal history of breast cancer. Enrollment started in January 2019 and is on-going. An interim data analysis was performed. Women were invited to undergo supplemental CEM screening within 180 days of negative (BI-RADS 1 or 2) conventional 2D/3D screening mammography (MG). Patients with prior screening MBI, ultrasound or MR imaging within 12 months were excluded from study participation. Outcome measures were supplemental cancer detection rates, sensitivity, specificity, positive predictive value, and negative predictive value of CEM, along with their 95% confidence intervals, as well as the biologic profiles of MG-occult, CEM detected cancers. Results: A total of 351 women were enrolled in this prospective study over a 20-month period. To date, we have 1 year follow up on 106 cases with negative follow-up MG. Average age of the participants was 56 years ± 9.44 (standard deviation); 11 patients had screening 2D MG, 333 had combined 3-D and 2-D screening MG; 309 dense and 37 non-dense breasts based on ACR BI-RADS categories. CEM depicted 8 additional breast cancers (table 1), which were otherwise MG occult, for an overall supplemental cancer detection rate of 22.7 per 1000 patients, 95% CI (9.9, 44.3). 1 false negative cancer on CEM imaging which was further detected on MR imaging only. Biopsy revealed 16 benign changes (16/28=57%), 4 high-risk lesions (4/28=14%), and 8 breast cancers (8/28=29%) (table 2). CEM imaging screening offered high specificity (0.942, 95% CI (0.917, 0.967), high NPV 0.997, 95% CI (0.991, 1.000) and moderate PPV (0.286, 95% CI (0.118, 0.453) and sensitivity (0.889, 95% CI (0.684, 1.000)). Size of CEM detected cancers ranged from 7 to 57 mm. Conclusion: This pilot trial demonstrates a supplemental cancer detection rate of 22.7 per 1000 during prevalence round of CEM screening in women at an elevated risk for breast cancer. These initial results are comparable to results reported for high-risk surveillance MR imaging. Larger, multi-institutional high-risk CEM trials are needed for those patients who are not otherwise undergoing regular supplemental surveillance MR imaging. Citation Format: Bhavika K. Patel, Victor Pizzitola, Donald Northfelt, Karen Anderson, Marina Giurescu, Gina Mazza, Roxanne Lorans, William Eversman, Richard Sharpe, Juliana Kling, Denise Millstine, Ernst Brenda, Patricia Cronin, Heidi Apsey, Jennifer Palmieri, Barbara Pockaj, Michele Halyard. Supplemental contrast enhanced mammography screening of women with elevated risk of 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 PS2-41.

Abstract Introduction: The immune microenvironment of high-risk HR+ breast cancer (BC) is poorly understood. BEAUTY is a prospective neoadjuvant chemotherapy (NAC) study of stage I-III BC patients treated with neoadjuvant weekly taxane followed by anthracycline-based chemotherapy. Among clinical luminal B BC (St. Gallen criteria) from BEAUTY, we used high-plex digital spatial profiling (DSP) to characterize the intra-epithelial tumor and stromal immune landscapes to 1) assess the impact of NAC on these landscapes and 2) identify immune biomarkers predictive of response to NAC. Methods: The tissue set included FFPE sections of resected tumors from 35 patients (median 51y; range: 21-71y) with clinically-defined luminal B BC (ER &gt; 10%/grade 2/Ki67 ≥ 15% or ER &gt; 10%/grade 3), and 16 paired pre-NAC biopsies. Nanostring GeoMX DSP was used to quantitate 58 immune and BC biomarker proteins in intra-epithelial, cytokeratin-positive tumor segments and adjacent stromal (cytokeratin-negative/SYTO13 (nuclear stain)-positive) segments. Data were normalized using the geometric mean of two negative controls (RbIgG and MsIgG1). A general linear model with negative binomial identified differentially-expressed (DE) proteins in pre/post-NAC tumors. Based on DE protein data and biologic function, a targeted protein subset (N=19) was evaluated in pre-NAC biopsies for associations between protein abundance and residual cancer burden (RCB) class (0-II vs. III) (Wilcoxon-rank sum test: p-value &lt; 0.025 considered significant) or RCB ‘breast only’ index (Spearman correlation). Results: Comparing tumor segments in pre-NAC specimens, intra-epithelial segments were predictably enriched in cytokeratin, ER, PR and Ki-67, but also CD127 and NY-ESO-1; whereas stromal segments were enriched in proteins associated with T cell subsets (e.g. CD3, CD4, CD8), macrophages (CD68 and CD163), antigen presentation/dendritic cells (CD11c, HLA-DR) and immune checkpoint proteins (PD-L1, PD-L2, B7-H3, TIM-3, VISTA) among others. While NAC did not alter the spatial distribution of proteins (intra-epithelial vs. stromal segments), it markedly attenuated the immune landscape, with decreased abundance of functionally-diverse immune proteins (e.g. CD45, CD3, CD4, CD127, granzyme B, CTLA4; STING, B7-H3, CD11c, and CD68, log2FC: 0.27-1.52 p &lt; 0.05), including low abundance proteins PD-1, PD-L1, PD-L2, CD20, and OX40L (log 2FC: 0.15-1.16, p &lt; 0.05). Both PR and Ki-67 decreased in post-NAC tumors whereas ER was not significantly altered (p &lt; 0.05). CD8, CD14, CD163, HLA-DR, IDO-1 and TIM-3 were not significantly altered by NAC. In the pre-NAC biopsies (which had subsequent residual tumor burdens of RCB class 0 or I (n=1 each), II (n=6), and III (n=8), and median RCB ‘breast only’ index of 3.39 (range: 0.00-38.02), 19 proteins were used for RCB analysis (CD3, CD4, CD8, CD14, CD34, CD44, CD45, CD68, CD127, CD163, CTLA4, granzyme B, STING, B7-H3, fibronectin, Ki-67, HLA-DR, SMA and TIM3). Among them, stromal CD127 was significantly higher in RCB class III than RCB class 0-II (p=0.021) and RCB ‘breast only’ index was positively correlated with intra-epithelial granzyme B (rho = 0.61; p=0.012), and negatively correlated with intra-epithelial Ki-67 (rho= -0.71; p=0.0022). Conclusion: In this series of clinical luminal B BC, NAC markedly attenuated the tumoral immune landscapes with a small set of “NAC-resistant” immune proteins. Among a targeted set, stromal CD127 was significantly higher in RCB III, and RCB breast-only index was positively correlated with intra-epithelial granzyme B. These data provide insight into the impact of NAC on HR+ BC, and identify potential immune biomarkers to predict response to neoadjuvant chemotherapy. Citation Format: Jodi M Carter, Judy C Boughey, Jun He, Vera J Suman, Xue Wang, Jennifer M Kachergus, Krishna R Kalari, Liewei Wang, Richard Weinshilboum, Ann M Moyer, Sarah A McLaughlin, Alvaro Moreno-Aspitia, Donald W Northfelt, Richard J Gray, James N Ingle, E. Aubrey Thompson, Matthew P Goetz. Neoadjuvant chemotherapy selectively alters spatially-defined immune landscapes in clinical luminal B HR+/HER2- breast cancers: Analysis of the breast cancer genome guided therapy study (BEAUTY) [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 PD7-05.

Abstract Background: Patient derived xenografts are a standard tool used to study cancer biology and evaluate drug response phenotypes. It is well known that PDX take rate is associated with more aggressive clinical features [higher grade, biologic subtype (e.g. TNBC vs luminal)]. Previous data from a small retrospective cohort of patients (pts) with no prior chemo (n=24) suggested that primary breast tumor PDX take rate was associated with reduced overall survival. (Derose Nat Med. 2011) However, whether take rate is prognostic in newly diagnosed pts receiving standard of care neoadjuvant chemotherapy (NAC) is unknown. From the prospective BEAUTY clinical trial of pts treated with NAC in which PDX was attempted from pre-NAC as well as after chemo (post-NAC), we recently reported no difference in take rate comparing pts with or without a pathologic complete response (pCR) (Yu Breast Canc Res 2018). Herein we report the association between PDX take rate and recurrence from tumor samples implanted pre-NAC as well as post-NAC (time of surgery). Methods: The BEAUTY study is a prospective NAC study which enrolled breast cancer pts (Stage I-III; n=140) treated with neoadjuvant weekly taxane +/-trastuzumab followed by anthracycline-based chemotherapy. Percutaneous tumor biopsies were obtained prior to NAC and tumor samples from residual disease at surgery were additionally used to establish PDXs. Tumor take rate was defined as percent of pts with the development of at least one stably transplantable (passed at least for four generations) xenograft that was pathologically confirmed as breast cancer. Time to breast cancer recurrence was defined as the time from surgery to documentation of a local, regional, or distant recurrence. Gray’s test was used to assess whether the cumulative incidence (CI) of a breast cancer recurrence differs with respect to either pre-NAC PDX take or post-NAC PDX take. Results: Of 140 pts enrolled in the BEAUTY study, tumor tissue for PDX from the pre-NAC tumor was available for implantation in 113. As previously published, PDX take rate from pre-NAC tumor was 27.4% (31/113), and varied according to tumor clinical subtype [51.3% (20/39) in triple negative breast cancer (TNBC), 26.5% (9/34) in HER2+, 5.0% (2/40) in Luminal]. With median follow up of 5.7 years (range: 3 months to 6.75 years), 17 pts developed local, regional or distant disease relapse (4 of whom had a PDX established pre-NAC). The cumulative incidence of breast cancer relapse after surgery was not found to differ according to pre-NAC PDX take (5 yr CI rate: 13.6% no take; 13.4% take; p=0.8911). In pts with TNBC, the group with the highest take rate, there was also no significant difference in incidence of BC recurrence between those without PDX take and those with PDX take (5 yr CI rate: 21.4% vs 16.2% p=0.7314). PDXs were established from residual tissue from surgery (post-NAC) in 6 of 34 pts (17.6%), [specifically, TNBC: 5/9; Her2+: 1/8; and Luminal: 0/17]. Nine of these 34 pts developed a local, regional or distant recurrence. There was a tendency for pts who had a PDX established from their residual disease to have a higher incidence of a breast event (p=0.1092). The 5 year cumulative incidence of a breast event was 19.6% for pts whose post-NAC PDX did not take and 50.0% for pts whose post-NAC PDX took. Discussion: In pts receiving NAC for breast cancer, we observed no significant difference between establishment of a pre-NAC PDX and breast cancer relapse. In contrast, post-NAC PDX take rate (from residual tumor obtained from the breast at surgery) was associated with a tendency to have a higher incidence of a breast cancer event. PDXs remain a valuable tool for the evaluation of tumor biology and development of new therapeutics, especially those models established from pts with chemotherapy resistance. Citation Format: Judy C. Boughey, Vera J. Suman, Jia Yu, Katelyn Santo, Jason P. Sinnwell, Jodi M. Carter, Krishna R. Kalari, Xiaojia Tang, Sarah A. McLaughlin, Alvaro Moreno Aspitia, John A. Copland, III, Donald W. Northfelt, Richard J. Gray, Katie N. Hunt, Amy Lynn Conners, Richard Weinshilboum, Liewei Wang, Matthew P. Goetz. Association between patient derived xenograft (PDX) take rate and breast cancer recurrence in the prospective breast cancer genome guided therapy study (BEAUTY) [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 PD7-04.

Abstract Background Inhibition of PD-L1 with atezolizumab combined with chemotherapy has shown acceptable safety and improved survival in patients with metastatic PD-L1 positive triple negative breast cancer (TNBC). Patients with TNBC who do not achieve a pathological complete response (pCR) to neoadjuvant chemotherapy have a high risk of disease recurrence and death. This randomized, open-label, phase 2 trial evaluates neoadjuvant carboplatin and paclitaxel with or without atezolizumab in patients with previously untreated clinical stages II and III TNBC. Methods Women aged ≥18 years with clinical stage T2-T4c, any N, M0 primary tumor by AJCC 7th edition staging TNBC; ECOG PS 0-2; and no prior systemic therapy for the indexed breast cancer were eligible. Patients were randomized in a 1:2 ratio to carboplatin AUC5 q 3 weeks x 4 + paclitaxel 80 mg/m2 q week x 12 (Arm A), or carboplatin AUC5 q 3 weeks x 4 + paclitaxel 80 mg/m2 q week x 12 + atezolizumab 1200 mg q3 weeks x 4 (Arm B). Surgery was 3-6 weeks following neoadjuvant chemotherapy. Adjuvant dose-dense doxorubicin and cyclophosphamide was administered q2 weeks with growth factor support to all patients as per routine care. pCR and tumor infiltrating lymphocyte (TIL) percentages are the co-primary endpoints. pCR-evaluable population includes all eligible women who have been randomized and received at least one dose of combination therapy, while the TIL-evaluable population includes all eligible women who have evaluable TIL percentage after one cycle of therapy. A sample size of 67 (22 in Arm A, and 45 in Arm B) provided 80% power at 1-sided alpha = 0.10 to detect a minimum of 15% difference in TIL and 29% improvement (40% vs. 69%) in pCR, respectively. Herein, we report pCR results in the per protocol modified intent-to-treat population (mITT), which includes all eligible patients who were randomized and received at least one dose of combination therapy. Results Sixty-seven patients were randomized between 8/2017 and 9/2019. Six patients randomized to Arm A withdrew consent; 2 of these received protocol therapy but are excluded from the mITT analyses as they are not evaluable because definitive pathology reports are not available. Median follow up is 6 months (range 0.3 - 12.6 months). Median age is 52 years (range 25 - 78). Forty-three (64.2%) were Caucasian and thirteen (19.4%) were African American. Twenty-five (37.3%) were pre-menopausal. 67.2% and 32.8% had stages II and III disease respectively. Nine (13.4%) had a germline mutation in either BRCA1 or BRCA2. In the mITT population, 3 of 16 patients achieved pCR in Arm A - 18.8% (95% CI 4.0%- 45.6%), versus 25 of 45 patients in Arm B - 55.6% (95% CI 40.0%-70.4%); p value 0.018. pCR in those with BRCA mutations was 50% and 80% in Arm A and Arm B, respectively. Treatment delays were observed in 9 patients (40.9%) in Arm A, and 20 (44.4%) in Arm B; dose reductions occurred in 4 patients (18.1%) in Arm A, and in 6 (13.3%) in Arm B. There were 4 SAEs in Arm A and 10 in Arm B. One patient in Arm B had grade 3 adrenal insufficiency. One patient in Arm B died from recurrent disease during the follow-up period. Conclusions: The addition of atezolizumab to neoadjuvant carboplatin and paclitaxel resulted in an increased pCR rate in patients with clinical stages II and III TNBC. However, the pCR in the control Arm A was lower than expected, possibly due to the absence of neoadjuvant anthracyclines. The high pCR rate observed in the experimental arm of this study is similar to that observed in other neoadjuvant trials utilizing anthracyclines, taxanes, and carboplatin in TNBC. Clinical trial information: NCT02883062. Citation Format: Foluso O Ademuyiwa, Feng Gao, Ina Chen, Donald W Northfelt, Robert Wesolowski, Mili Arora, Adam Brufsky, Claire Dees, Cesar A Santa-Maria, Roisin M Connolly, Jeremy Force, Alvaro Moreno-Aspitia, Sarah Larson, Elad Sharon, William Gillanders. Nci 10013 - A randomized phase 2 study of neoadjuvant carboplatin and paclitaxel, with or without atezolizumab in triple negative breast cancer (TNBC) [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 PD14-09.

Abstract Background: Hereditary factors play a key role in the risk of developing breast cancers. Identification of a germline predisposition can have important implications for treatment decisions, risk-reducing interventions, cancer screening, and testing for family members. Aim: To determine the prevalence of pathogenic or likely pathogenic germline mutations (P/LP) using a “universal” testing approach and uptake of no-cost cascade family testing in patients with breast cancer. Methods: We undertook a prospective multi-site study of germline genetic alterations among breast cancer patients receiving care at Mayo Clinic cancer centers in Rochester, MN; Eau Claire, WI; Jacksonville, FL and Phoenix, AZ between April 1, 2018 and March 31, 2020. Patients with a new or active breast cancer diagnosis (all stages) irrespective of cancer family history were tested with a &gt;80-gene next generation sequencing panel.Results: Of 390 patients, the median age was 58 years (SD 12.3), 1% were male, 85% were white and 28% had advanced (stage 3-4) disease. P/LP were found in 12.1% (n=47) of patients, including 29 in moderate and high penetrance cancer susceptibility genes. 13 (3.3%) patients had mutations in BRCA1 or 2, while 33 (8.4%) had mutations in BRCAness (ATM, BAP1, BARD1, BLM, BRCA1, BRCA2, BRIP1, CHEK2, NBN, PALB2, RAD50, RAD51C, RAD51D, WRN) associated genes. Of the P/LP findings the most frequent aberrations were in BRCA2 (13.5%), BRCA1 (11.5%), CHEK2 (11.5%), MUTYH (11.5%), and WRN (9.6%). Variants of uncertain significance were found in 209 (53.6%) including 26 (6.6%) with concurrent P/LP and VUS. 37 (9.4%) patients had mutations associated with published management recommendations, precision therapies and/or clinical trial eligibility. 10 (2.6%) patients had P/LP that would not have met current screening guidelines, including 4 with moderate or high penetrance mutations. Patients with younger age of diagnosis were less likely than patients with older age of diagnosis to have a P/LP mutation (OR= 0.47, 95%CI: 0.25-0.90 p = 0.020). Only 10 (21%) patients with P/LP had family members undergo familial site- specific testing at no cost.Conclusions: In this prospective multi-center study of unselected breast cancer patients, universal multi-gene panel testing found that 1 in 8 patients harbor P/LP germline variants. Current guidelines were able to identify the majority of patients with P/LP mutations. Familial site specific testing is greatly under-utilized even when cost is not a barrier. Multigene panels impact cancer patient care by identifying precision medicine treatment interventions, and guiding long-term medical management and preventive surveillance. Citation Format: Brenda Ernst, Natalie Ertz-Archambault, Deborah J Rhodes, Donald W Northfelt, Myra Wick, Douglas L Riegert-Johnson, Scott Okuno, Katie Kunze, Michael Golafshar, Cindy M Azevedo, PLS Uson Junior, ED Esplin, Robert Nussbaum, Margaret Klint, Sarah Mantia, Megan Hager, Keith Stewart, Niloy Jewel Samadder. Universal genetic testing in breast cancer patients: A multi-center prospective study [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 PD10-05.

Introduction: Serum folate (SF), vitamin B12 (B12), and iron deficiency (def) are common causes of nutritional anemias (NA). These deficiencies are usually multifactorial, with nutritional and non-nutritional causes playing a role. SF, B12, and iron levels are usually ordered in the setting of anemia, and malnutrition with or without neurologic symptoms. Clinical evidence suggests that these def have a strong dietary component and socioeconomic status (SES). The relationship of NA and area-based SES in the US has not been studied. We aimed to determine the relationship of SES with the prevalence of NA. Methods: We performed a cross-sectional analysis of adult patients with SF, B12 and iron levels at Mayo Clinic Arizona and Florida between 2010 and 2018. Race was classified using the NIH criteria. Normal laboratory values were determined according to our lab reference and the US NHANES III. SF levels (mcg/Lt) were defined as deficient &lt;4, normal ≥4.0, and excess ≥20. B12 levels (ng/L) as deficient &lt;150, borderline 150-400, normal &gt;400-900, and excess ≥900. Iron def was determined by ferritin levels (mcg/L) as low &lt;24, normal 24-336, elevated &gt;336 for men, low &lt;11, normal 11-307, elevated &gt;307 for women. Area-Level SES indicators: Median Household income (MHI), unemployment rate (UR), median gross rent month (MGRM), % uninsured, median house value (MHV), % high school; were geocoded by zip code using the 2014 American Community Survey. Demographics and clinical variables were compared between groups by chi-square test for frequency data or Kruskal Wallis rank-sum test for continuous variables. Results: 202,046 samples from 128,084 patients were analyzed. In the sample-level analysis, there were statistically significant associations between SES and SF def; all SES indicators except UR for B12 def; and no differences for iron def, except % uninsured (Table 1). There was no statistically significant interaction between race and SES for SF def and iron def. Race was a statistically significant modifier between B12 def and MHI (p&lt;0.001), % uninsured (p=0.002), and MHV (p=0.007). Asian and Other race had an increase in odds of B12 def with increasing MHI (Asian OR=1.11 , Other OR=1.18); white race had a decrease in odds of B12 def with increasing MHI (OR=0.95 for a $10,000 increase in MHI). Conclusions: We show significant relationships between SES and NA in the US. Differences were observed between SF def and all the SES indicators without race interactions. There were significant interactions between B12 def, race and SES for pts of White, Asian and Other race. There were no differences between SES and race for iron def. These relationships confirm that NA are related to area-level SES and other social determinants of health. Research regarding the causes of these disparities on a population level are needed. Disclosures No relevant conflicts of interest to declare.