Results of the safety run-in of gedatolisib plus talazoparib in advanced triple negative or BRCA 1/2 positive HER2 negative breast cancer

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Background: Metastatic triple negative breast cancer (TNBC) is a disease subtype with a poor prognosis, though advancements have been made in the use of targeted therapies, such as poly (ADP-ribose) polymerase inhibitors (PARPi) for those with germline BRCA 1/2 mutations. Up to 2/3 of TNBC tumors have acquired defects in homologous recombination (HR) DNA repair, yet PARPi monotherapy has been ineffective in extending survival in these patients. Phosphoinositide-3-kinase (PI3K)/mTOR pathway alterations are also common, and preclinical data supports that PI3K/mTOR inhibition may disrupt normal function of the HR complex and increase dependency on PARP enzymes for HR DNA repair. Thus, combining a PI3K/mTORi with a PARPi may result in a synergistic anti-neoplastic effect. Methods: The safety run-in portion of this study evaluated the safety and preliminary efficacy of the combination of weekly IV gedatolisib (PI3K/mTORi) and continuous daily talazoparib. Germline BRCA mutations were not required. The safety run-in was designed to determine the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D). A 3+3 design was utilized for dose escalation, with starting dose at level 1. Dose levels are as shown in the Table. Eligibility criteria included patients ≥ age 18 who had received 1-3 prior lines of therapy for advanced TNBC or advanced HER2-negative BC with a germline BRCA 1/2 mutation. Those with untreated CNS metastasis were excluded as were those type I diabetes or uncontrolled type II diabetes, due to the risk of hyperglycemia with gedatolisib. Results: A total of 14 female patients were enrolled on to the safety run-in phase of the trial. Median age was 53 (range 30-67). Most patients (79%) were Caucasian, 14% were African American, and 7% unknown. The most common adverse events (AEs) of any grade were fatigue, anemia, nausea, and oral mucositis. Grade 1 hyperglycemia was noted in about 1/3 of the cohort, with 1 grade 3 event. There were 3 patients who experienced grade 4 AEs, thrombocytopenia (2) and lymphopenia (1). There was 1 DLT of grade 3 neutropenia which occurred at dose level 1. The MTD of gedatolisib was 180 mg and MTD of talazoparib was 1 mg. In this preliminary cohort, 3 patients achieved PR and 5 patients achieved SD. Median duration of PR was 13.34 months and median duration of SD was 4.11 months. Of the 3 patients with a BRCA 1 or 2 mutation, 2 had a best response of PR and the other SD. Conclusions: The safety run-in indicated that this combination is safe and well tolerated with mostly grade 1-2 AEs. This combination therapy has moved into the phase II trial, with 2 cohorts. Cohort A includes BRCA-wildtype patients with TNBC and cohort 2 includes those with a BRCA mutation and HER2-negative disease. Clinical trial information: NCT03911973. [Table: see text]

Identification of exosome protein biomarkers in patients with advanced hormone receptor-positive breast cancer treated with palbociclib and tamoxifen

e13014

Background: The combination of a CDK4/6 inhibitor (CDK4/6i) plus endocrine therapy (ET) doubles progression free survival compared with ET alone in hormone receptor (HR)-positive, advanced breast cancer (BC), although not all patients respond and responders eventually develop resistance and disease progression. Exosomes are membrane-bound extracellular vesicles that are released from tumors for cell-to-cell transfer of lipids, proteins, and nucleic acids. Analysis of exosome cargo provides a dynamic and functional read-out of biological pathways that are activated in cancer cells. We performed deep proteomic analysis of plasma exosomes from patients receiving palbociclib/tamoxifen to identify protein networks that predict response to CDK4/6i and ET and that may contribute to drug resistance. Methods: The Big Ten Cancer Research Consortium conducted a phase II trial of palbociclib plus tamoxifen as first line therapy for patients with advanced, HR+/HER2- BC (NCT02668666). Whole blood was collected in Streck tubes from all participants at baseline and at time points during study treatment. Plasma was separated and stored at -80C within 48 hours of collection. Exosome extraction and purification was optimized for maximum proteomic coverage. Proteins were labeled with tandem mass tag 10plex and quantified with ultrasensitive mass spectrometry. Detected proteins were mapped to pathways with the Reactome Pathway Database. An unsupervised machine learning approach with modified graphic neural networks was used to determine whether differential expression of protein networks in plasma exosomes predicts treatment response. Results: We detected more than 700 exosome proteins from100 μl plasma in 16 study participants (responders, n = 11; non-responders, n = 5). Significant enrichment of exosome-specific markers was observed when comparing patient samples with healthy donor samples. Exosomal protein networks in pretreatment samples predicted treatment response with 95% sensitivity and 85% specificity in unsupervised clustering. The top weighted protein networks in the treatment response model are enriched for membrane attack complex, complement activation and lipoprotein receptor binding pathways. Conclusions: Ultrasensitive proteomic analysis combined with deep learning methods provides a detailed picture of the proteome landscape of plasma exosomes in advanced breast cancer patients and is ideally suited for serial analyses to study emergence of resistance mechanisms. This approach also demonstrated unparalleled accuracy as a predictive biomarker to identify patients unlikely to respond to CDK4/6i and ET. If results are confirmed, this novel approach could hold great promise for identifying protein biomarkers and mechanisms of resistance that emerge during anticancer therapy. Clinical trial information: NCT02668666.

A phase II, single-arm, non-randomized study of alpelisib (BYL719) in combination with continued endocrine therapy following progression on endocrine therapy in hormone receptor–positive, HER2-negative, PIK3CA-mutant metastatic breast cancer: A Big Ten Cancer Research Consortium Study (btcrc-BRE19-409)

TPS1114

Background: The PI3K pathway is frequently altered in hormone receptor positive (HR+) breast cancer (BC) and 40% of patients have PIK3CA mutations. The PI3Kα-specific inihibitor, Alpelisib, is FDA-approved in combination with fulvestrant for treatment of patients with HR+ HER2 negative (HER2-) PIK3CA mutated, advanced BC following progression on or after a non-fulvestrant endocrine therapy (ET) based regimen. We hypothesized that the benefit seen in the seminal SOLAR-1 study that compared alpelisib plus fulvestrant to placebo with fulvestrant, was due to the addition of alpelisib, rather than the change to fulvestrant, such that addition of alpelisib to ongoing ET at time of progression could lead to similar outcomes. Unlike SOLAR-1, our study continues prior ET at time of progression and requires prior CDK4/6 inhibitor therapy. Methods: We designed a phase II single arm study that tests the efficacy of adding alpelisib to ongoing ET at time of progression on ET. The primary objective is to estimate the progression–free survival (PFS) of alpelisib with continued ET (aromatase inhibitor or fulvestrant) following progression in patients with HR+ HER2-, PIK3CA mutant advanced BC. Secondary objectives are to estimate overall response rate, clinical benefit rate, duration of response, overall survival and safety/tolerability. Correlative studies include evaluation of PIK3CA activity in circulating tumor cell liquid biopsy at baseline, C1D15, C2D1, C4D1 and at progression and correlation with primary and secondary objectives. Eligibility: Men and postmenopausal female patients with histologically confirmed ER and/or PR ≥1%, HER2- metastatic or unresectable BC with PIK3CA mutation and either measurable disease or at least one predominantly lytic bone lesion. No more than two lines of ET and no chemotherapy in the metastatic setting is allowed and patients must have received treatment with a CDK4/6 inhibitor and have progressed on ET as last line of therapy. Exclusions include prior PIK3CA, mTOR or AKT inhibitors in the metastatic setting, symptomatic active CNS metastases or CNS metastases that require therapeutic interventions. Statistical Analysis. The sample size calculation is based on testing the null hypothesis that the median PFS is at most 5 months against the alternative that the PFS is greater than 5 months (based on data from SOLAR-1). An increase of at least 3 months in the median PFS will be considered a sufficient efficacy signal. A sample size of 44 subjects is required to detect an anticipated increase in the median PFS from 5 to 8 months at the one-sided 0.10 significance level with 90% power, assuming a uniform accrual period of 24 months. Clinical trial information: NCT04762979.

Molecular characterization of luminal breast tumors in African American women

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Background: Racial disparities in breast cancer (BC) mortality are attributed to later stage diagnoses and a higher incidence of triple-negative BC among African American (AA) women. In previous work, we showed that AA women with ER+ BC are more likely to develop biologically aggressive disease and are more likely to die from early stage, ER+ BC than non-Hispanic White women (Hoskins et al, JAMA Oncol, 2021). The underlying molecular drivers of this disparity are unknown. Here we report the molecular characterization of a series of luminal BC from AA women. Methods: Consecutive breast tumor specimens received in the Pathology Department underwent next generation sequencing (NGS). Unstained FFPE tissue sections were macro-dissected to isolate tumor cells, and nucleic acids were extracted using commercially available kits. DNA and RNA sequencing libraries were prepared with the Oncomine Comprehensive Assay v3 (OCAv3) (Thermo Fisher), which includes 161 driver genes and detects SNVs, CNVs, INDELs and gene fusions. Sequencing was performed on the Ion S5XL sequencer. Sequencing reads were mapped to the UCSC human genome build GRCh37/hg19 using Torrent Suite™ software (version 5.10; Thermo Fisher). Data analysis and variant calling was performed using the Ion Reporter analysis tool. Results: We identified 60 somatic driver gene alterations in luminal tumors from 35 AA patients (primary tumors, n = 26; metastatic tumors, n = 9). Recurrently altered genes identified in > 5% of tumors are listed in the Table. The most frequently altered gene was PIK3CA (42% of tumors). ESR1 gene fusions were seen in 25% of tumors. Interestingly, an equal frequency of ESR1 fusions were detected in primary (27%) and metastatic (22%) tumors, in contrast to activating mutations which are found in recurrent tumors following treatment with aromatase inhibitors. ARID1A alterations were identified in 17% of primary tumors. ARID1A encodes a subunit of the SWI/SNF chromatin remodeling complex. Alterations in ARID1A confer endocrine resistance, and are enriched in recurrent tumors in the literature. We also found a high number of CNVs in members of the FGF gene family (36% of tumors), which are also associated with resistance to endocrine therapy. An in silico analysis comparing our findings with publicly available datasets will be presented. Conclusions: This study of somatic driver gene alterations in a consecutive series of luminal breast tumors from AA patients found a higher than expected frequency of alterations in genes associated with endocrine resistance in untreated primary tumors, suggesting a partial explanation for racial disparities in survival.[Table: see text]

What accounts for the racial disparity in survival from estrogen receptor-positive, axillary node-negative breast cancer in the United States? An analysis of the SEER-Oncotype database

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Background: In a previous analysis of the SEER-Oncotype database (Hoskins, et al. JAMA Oncol, 2021), we reported that among women with estrogen receptor (ER)-positive, axillary node-negative breast cancer (BC), Black women were more likely than non-Hispanic White (White) women to have a high risk Oncotype Recurrence Score (RS), and the adjusted hazard for BC-specific death was 1.5-2.5 times higher for Black than for White women within each RS risk category. In this study we examined the role of health insurance, census tract socioeconomic status and tumor biology in the racial disparity in ER-positive BC mortality among US women. Methods: We obtained BC-specific survival data from the SEER-Oncotype database for women diagnosed with first primary, stages I-II, ER-positive, node-negative BC between 1/1/2004 -12/31/2015 who had an Oncotype Recurrence Score (RS) through Genomic Health Laboratory. The racial (Black:White) BC mortality disparity was estimated as a disparity hazard ratio (HR) from a series of Cox proportional hazards models of time to BC death. The baseline model adjusted for SEER registry and age at diagnosis (included in all models). We estimated the disparity HR after controlling for variable domains one at a time, as well as cumulatively in this order: neighborhood SES index (a composite measure including census tract education, income and poverty) and insurance (none, public, private); tumor biology (RS, PR status, tumor grade); tumor size; and treatment (surgery type, initiation of radiation and chemotherapy). Results: The analysis included 57,428 White and 6,003 Black women with node-negative, ER-positive BC (median follow-up = 54 months). The total disparity HR for BC death was 1.67 (95% CI: 1.37, 2.02). Tract SES and insurance together accounted for 21% of the disparity HR (adjusted HR 1.52, 95% CI: 1.22, 1.88); most of this was due to differences in insurance status, with tract SES accounting for 7% of the disparity when considered in isolation. Tumor biology (RS, PR status and grade) accounted for 30% of the disparity (adjusted HR = 1.41, 95% CI:1.14, 1.75); together, the domains of social determinants and tumor biology accounted for 50% of the disparity HR (adjusted HR = 1.30, 95% CI: 1.04, 1.62). Tumor size and treatment initiation each explained roughly 10% of the disparity HR when considered in isolation but did not account for any of the disparity once other factors were accounted for. Results obtained from additional methods for mediation analyses, including a method of rescaled coefficients and structural equation modeling (SEM) applied to discrete-time survival analysis will also be presented. Conclusions: In this study of node-negative, ER-positive BC, much of the BC survival disparity among US women could be explained by racial differences in measured tumor biology and social determinants of health.

Disparities within luminal breast cancer: Clinical and molecular features of African American and non-Hispanic white patients

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Background: African American breast cancer patients (AA) are diagnosed younger, have more high-risk features, and poorer clinical outcomes than non-Hispanic White patients (NHW), despite similar treatments. Although comorbidities such as obesity and metabolic syndrome may contribute to differences, ancestry-specific factors and effects of structural violence that disproportionately afflict AA individuals may influence tumor biology and outcomes. We previously reported differentially expressed genes (DEGs) associated with tumor aggressiveness in Basal tumors from AA compared with NHW (Sharma et al., 2020). Here, we compare DEGs in luminal tumors between AA and NHW. Methods: The prospective, observational FLEX study (NCT03053193) includes stage I-III breast cancer patients who receive 70-gene signature (MammaPrint/MP)/80-gene signature (BluePrint/BP) testing and consent to full transcriptome and clinical data collection. AA (n=364) and NHW (n=400, random selection) with BP luminal tumors, enrolled from 2017 to present, were included. Race/ethnicity was self-reported. AA were younger than NHW (mean, 59 vs. 62 years, p=0.001); thus, an age-matched subset (n= 360 AA, NHW) was compared. Differential gene expression analysis was performed with R limma package. Comparisons were made between AA and age-matched or randomly selected NHW in: (1) all, (2) luminal A, (3) luminal B, and (4) luminal B, obese. DEGs with FDR<0.05 were significant. Different fold change (FC) thresholds were evaluated. Results: Compared with age-matched NHW, AA were similar in menopausal status, T stage, grade, and tumor type; obesity, T2DM status, and nodal stage were significantly different ( p<0.01). Tumors from AA were more often MP high risk ( p<0.001), regardless of age matching. Luminal B AA vs. age-matched NHW comparison resulted in more DEGs (n=1070) than other comparisons; however, most were FC<2. Notably, 5/6 DEGs ( PSPH, NOTCH2NL, POLR1A, MAP1LC3P and RPS26P10) in basal tumors (Nunes et al. 2019) were also identified here. Of 9 DEGs (FC>1.7) in the luminal B age-matched comparison, 2 ( PSPH and LINC01139) were also found in the luminal B, obese subset. Consistently upregulated DEGs in AA were associated with metabolism, translation, and cellular stress response pathways. Conclusions: We found significant transcriptomic differences between luminal tumors from AA and NHW, when controlling for age, obesity, and genomic classification. A subset of DEGs in luminal B tumors were consistent with those in Basal tumors, suggesting that similar race-associated factors drive DEGs regardless of tumor subtype. DEGs that may be unique to AA luminal tumors were also found. This study suggests that some biological differences in breast tumors may result from patient ancestry or shared adverse socioeconomic exposures and underscores the need for inclusion of diverse patient groups in clinical trials. Clinical trial information: NCT03053193.

Deep proteomic analysis of plasma exosomes in patients with advanced, hormone receptor-positive breast cancer treated with palbociclib and tamoxifen

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Background: Combining a CDK4/6 inhibitor (CDK4/6i) with endocrine therapy (ET) in advanced, hormone receptor (HR)-positive, HER2-negative breast cancer (BC) doubles median progression-free survival, but eventually drug resistance and disease progression occur. For most patients, the mechanism of resistance is unknown. Exosomes are membrane-bound extracellular vesicles that contain lipids, proteins, and nucleic acids, and are released from tumors as a form of intercellular communication. Exosomes can be recovered from plasma, and analysis of their cargo provides a dynamic read-out of biological pathways that are activated in cancer cells. Proteomic analysis of plasma exosomes may provide insight into mechanisms of resistance that emerge during treatment with CDK4/6i-ET. Methods: The Big Ten Cancer Research Consortium conducted a single arm, phase II trial of palbociclib plus tamoxifen as first line therapy for advanced, HR+/HER2- BC (NCT02668666). Whole blood was collected in Streck tubes from study participants (n = 49) at baseline, at disease progression, and at time points during study treatment. Plasma was separated and stored at -80C within 48 hours of collection. Exosomes were isolated from thawed plasma using commercially available kits and ultracentrifugation. Exosome extraction and purification was optimized for protein recovery. Purified exosomes were processed for proteomic analysis and labeled with TMT10 (tandem mass tag 10plex) and quantified with the QExactive HF mass spectrometer. Ultrasensitive mass spectrometry provided deep proteomic coverage of exosomal proteins and detected various post-translational modifications (PTM). Data were analyzed with a pipeline developed in our lab using an improved SEQUEST/ProLuCID database search engine and Percolator data filtering toolchain. Exosome protein expression was determined at baseline, at best response and at the time of progression. Results: With our ultrasensitive proteomic method, we detected more than 500 exosome proteins from as little as 100 ng of purified exosomes. A significant enrichment of exosome specific markers was observed when comparing patient samples with healthy donor samples. Enrichment of surface glycoproteins (e.g. CD44) was seen in BC patient samples, as in previous reports. Ultrasensitive proteomics also detected PTM including phosphorylation, methylation, oxidation, deamidation, and glycosylation. Differential proteomic and PTM profiles comparing samples collected from responding patients at baseline vs. at progression will be presented. Conclusions: Our innovative method provided an unparalleled portrait of the proteomic landscape of plasma exosomes during treatment with CDK4/6i-ET. This powerful approach may provide novel insights into mechanisms of resistance that emerge during treatment. This study was funded by Pfizer. Clinical trial information: NCT02668666 .

A single-arm phase II trial of palbociclib in combination with tamoxifen as first-line therapy for metastatic hormone receptor-positive breast cancer

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Background: Palbociclib is a CDK4/6 inhibitor used to treat metastatic hormone receptor-positive (HR+) breast cancer (MBC) in combination with endocrine therapy. Tamoxifen is an effective treatment for HR+ MBC, with different toxicity profile compared with aromatase inhibitors (AI) and fulvestrant. Preclinical data demonstrated synergy for the combination of tamoxifen and palbociclib, being effective in a model of acquired tamoxifen resistance. Methods: We conducted an open-label, single-arm, multicenter phase II trial of palbociclib in combination with tamoxifen in patients with HR+/HER2 - advanced BC, with no prior therapy for MBC. Ovarian suppression was recommended for pre-menopausal women, but not required. Primary objective was progression free survival. Secondary objectives: objective response rate (CR or PR) based on RECIST 1.1 or MDA Criteria (for patients with bone only disease); safety and tolerability (using CTCAE v4); clinical benefit rate (CR, PR or SD lasting min 24 weeks); 2-year overall survival. Correlative objectives: proteomic analysis of plasma exosomes to identify mechanisms of primary and secondary resistance to tamoxifen/palbociclib. Results: Between 6/30/2016 and 7/02/2019, we enrolled 49 patients (47 evaluable): 23 pts with de-novo metastatic disease and 24 pts with recurrent BC (12 pts were on adjuvant treatment with AI at time of recurrence and 12 pts on surveillance). As of 1/5/21 data cut-off, 7 pts were still on treatment. Median follow-up time was 24 months (range 8-42). Median age was 60 (range 39-82). The median PFS was 14.6 months with 95% CI (7-41) for pts with de-novo MBC and 6 months (2-12) for pts with recurrent BC. The ORR was 30% overall, 39% for pts with de novo MBC, 21% for pts with recurrent BC. CBR was 64% overall, 78% for pts with de novo MBC and 50% for pts with recurrent BC. CBR was 65% for white pts and 55% for African American pts. Best response per RECIST1.1: 14 pts (34%) had PR, 18 pts (44%) had SD, 9 pts (22%) had PD. All 6 pts with bone only disease had SD. The most common drug related grade ≥ 3 AE was neutropenia (51%), transient and manageable by dose modifications, no cases of febrile neutropenia. Four patients developed thromboembolic events (1 grade 2, 2 grade 3, 1 grade 4). One patient died while on treatment from PD. Conclusions: The combination of palbociclib and tamoxifen showed tolerable, expected safety profile. This may be an alternative approach for selected patients in first line treatment of HR+ MBC, especially those who are intolerant to AI, although this small study indicates a lower PFS. Clinical trial information: 02668666 .[Table: see text]

Phase I study of procaspase activating compound -1 (PAC-1) in combination with temozolomide (TMZ) for the treatment of recurrent malignant glioma

TPS3164

Background: The caspase family of cysteine proteases play key roles in the initiation and execution of apoptosis. The activation of procaspase-3 to caspase-3 is critical in both the intrinsic and extrinsic apoptotic cascades. Procaspase-3 levels are elevated in many cancers, including glioblastoma (GBM). As a result, caspase-3 levels are abnormally low in these tumors; thus they avoid apoptosis. PAC-1 is a small molecule that directly activates procaspase-3 and induces apoptosis of cancer cells. PAC-1 has activity against a wide range of cancer cell lines, and in animal models of cancer. PAC-1 crosses the blood brain barrier and has been shown to synergize with TMZ in both canine malignant glioma and meningioma that arise spontaneously. Methods: This Phase I dose escalation study uses a modified- Fibonacci 3+3 design to determine the MTD of PAC-1 when combined with TMZ in patients with recurrent malignant gliomas: anaplastic astrocytoma (AA) and GBM (open to enrollment). Here, we focus on component 2 of the study. Primary objectives: to establish MTD of PAC-1 when combined with a fixed dose of TMZ, tolerability, and toxicity using CTCAE v.4. Secondary and correlative objectives: pharmacokinetics, pharmacodynamics, preliminary anti-tumor activity correlation with procaspase-3 expression in tumor tissue, radiographic response using the Response Assessment in Neuro-Oncology (RANO) criteria, and neurocognitive function using a validated test battery. Inclusion criteria: diagnosis of recurrent high grade glioma (AA or GBM), ECOG PS 0-2, adequate organ function. Exclusion criteria: received prior cytotoxic therapy in the last 3-6 weeks (duration based on prior therapy) or uncontrolled chronic illness. Administration and design, Component 2: PAC-1, orally administered, is dosed at 375-650 mg daily (up to 3 dose levels) on days 1-21 of each 28-day cycle. A fixed dose of TMZ, (150 mg/m2), is administered orally, days 8 -12 of each cycle. The study is currently enrolling patients for Component 2. Clinical trial information: NCT02355535.

Abstract OT3-05-10: A single arm phase II study of palbociclib in combination with tamoxifen as first line therapy for metastatic hormone receptor positive breast cancer

Background: Hormone receptor positive breast cancer is the most commonly diagnosed subset of breast cancer (60-65%). Endocrine therapy is effective for this subset of breast cancer, in both the adjuvant and metastatic settings. Despite advances in endocrine therapy, many patients relapse during or after completing adjuvant therapy and metastatic breast cancer remains incurable. Palbociclib is a reversible, oral, small molecule inhibitor of cyclin dependent kinases 4 and 6 (CDK4/6). CDK4 and CDK6 together with cyclin D have important roles in regulation of the G1/S transition via regulation of the phosphorylation state of retinoblastomaprotein (Rb). Palbociclib showed significantly improved progression-free survival taken together with endocrine agents in treatment of metastatic breast cancer. Preclinical data showed that in combination with tamoxifen, palbociclib had synergistic growth inhibitory activity as well as efficacy in a model of acquired tamoxifen resistance. Combining palbociclib with tamoxifen in first line treatment of metastatic hormone receptor positive breast cancer may offers an appealing alternative to other endocrine combinations. Methods: This is a non-randomized, open-label, single-arm, multicenter, phase II study of palbociclib in combination with tamoxifen in patients with hormone receptor positive/HER2 negative advanced breast cancer. The primary objective is to determine the objective response rate (complete or partial response) based on RECIST 1.1 or MDA Criteria (for patients with bone only disease). Secondary objectives are: safety and tolerability, progression-free survival, clinical benefit rate, 2-year overall survival. Correlative objectives will explore alterations in circulating tumor DNA and changes in gene expression pattern at the time of progression. Eligibility criteria: women or men with diagnosis of hormone receptor positive/ HER2 negative locally advanced or metastatic breast cancer, not amenable to curative surgery; no prior systemic anti-cancer therapy for advanced hormone receptor positive breast cancer; adequate organ function; pre and post menopausal women are allowed. Drug administration: palbociclib dose will be 125 mg orally once daily on days 1-21 of each 28-day cycle; tamoxifen dose will be 20 mg orally once daily for every day of the 28-day cycle. As of June 2017, the study enrolled 10/71 patients and it is still open to enrollment. NCT 02668666; ocdanciu@uic.edu

Citation Format: Danciu OC, Hoskins K, Tamkus D, Truica C, Blaes A, Green L, Liu L, Toppmeyer D, Wisinski K. A single arm phase II study of palbociclib in combination with tamoxifen as first line therapy for metastatic hormone receptor positive breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT3-05-10.

Supportive oncology and survivorship care: Initial impact of the Coleman Supportive Oncology Collaborative

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Background: The Institute of Medicine (IOM) and Commission on Cancer (CoC) recommend supportive oncology and survivorship care. The Coleman Supportive Oncology Collaborative (CSOC) aims to improve quality of supportive care and survivorship in Chicago. Methods: CSOC includes 35 institutions (cancer centers, support and hospice), structured in two design teams (Distress & Survivorship and Palliative). Participants identified opportunities and gaps in supportive and survivorship care in an iterative development of: screening tools, follow-up processes, provider training, and quality metrics to assess CSOC impact. Six process improvement sites (2 safety-net, 3 academic & 1 public) reviewed patient charts at baseline and Q1 2015, compared by Fisher’s exact test. Results: Eight metrics contained patient data at the 2 time points; improvements were seen in 6/8 metrics. Conclusions: CSOC successfully developed supportive oncology, survivorship screening, and care processes aligned with IOM and CoC standards. Significant improvements were shown after implementation in diverse settings. Ongoing work will continue to evaluate the impact of the CSOC on patient care. [Table: see text]

Measuring the impact of provider education to referral rate in survivorship care

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Background: There will be an estimated 19 million cancer survivors by 2024. Survivors are often lost to follow-up after active treatment due to poor coordination of care between clinical oncologist and primary care providers. Lack of awareness of survivor needs including insufficient monitoring of late effects after oncologic care contribute to poor care coordination. While cancer centers have gradually introduced survivorship care, it remains challenging for some providers to refer their patients to a survivorship visit once their cancer treatment is completed. Continuing education is known to improve provider knowledge and may lead to an increased number of patients referred to survivorship. Methods: Survivorship starts when completing the initial treatment (surgery, chemotherapy or radiation therapy). The project will implement the review of an education module regarding survivorship through the National Comprehensive Cancer Network (NCCN) education website by breast cancer (BC) medical oncologists and their fellows in training at a cancer center in the Midwest. Providers are to complete “Comprehensive Care for Cancer Survivors”, a free continuing education module, on the NCCN continuing education website. Pre intervention data was retrospectively collected, including all BC cases from June 2016 to August 2016. Post intervention data will be prospectively collected over 1 month. Pre and post intervention referral rates will be compared using descriptive statistical methods. Results: A baseline 3 months review of 349 encounters noted 22 of 28 (78.6%) BC survivors were referred to the breast cancer survivorship visit. Results for this project are ongoing, and will include the analysis of referral rates by medical oncologists or fellows during the 1 month post completion of the NCCN education module. These results will be compared to the previous 3 months Conclusions: While data collection is pending, we hope to show that providers who have completed formal education regarding survivorship are more likely to refer breast cancer survivors to a survivorship visit. If the project is effective it will help increase the number of cancer patients seen in the BC survivorship clinic and improve the health outcome of BC survivors.

Supportive Oncology Collaborative: Initial impact of supportive oncology screening and care

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Background: The Institute of Medicine (IOM) 2013 report recommends supportive oncology care from diagnosis through survivorship, to end of life. The Coleman Supportive Oncology Collaborative (CSOC) developed a city-wide plan to improve supportive oncology. Metrics derived from the Commission on Cancer (CoC), ASCO Quality Oncology Practice Initiative (ASCO-QOPI) and National Quality Forum (NQF) were used to assess the CSOC impact. Methods: Medical records of consecutive cancer patients from 6 practice improvement cancer centers in Chicago (3 academic, 2 safety-net, 1 public) were reviewed for 2 periods: 2014 (n = 843) and Q1 of 2015 (n = 313). Descriptive statistics assessed differences in quality metrics. Results: Significant improvement was achieved in 6 of 8 core supportive oncology metrics (see table). Conclusions: Consolidated metrics are feasible to assess supportive oncology quality. Early data indicate improvement and effectiveness of the collaborative approach. [Table: see text]

Abstract P4-10-02: Cancer team approach for implementing survivorship care plans in the breast cancer survivorship clinic

Background: Recommendations from the Institute of Medicine are that cancer patients receive individualized survivorship care plan (SCP) and treatment summary. SCP includes guidelines for monitoring and maintaining health and is a communication tool shared with families and health care providers. Offering SCP and treatment summary to cancer survivors remains challenging due to time and resource limitations, inadequate reimbursement and survivor access.

Methods: Survivorship starts when completing the initial treatment (surgery, chemotherapy or radiation therapy). A team of medical oncologists, nurse practitioner and patient navigator created a process of pre-screening and identifying breast cancer (BC) survivors. SCP and treatment summary were pre-populated, individualized for each patient, then finalized and discussed with the patients during their medical oncology clinic visit. Pre intervention data was retrospectively collected, including all BC cases from March 2014 to March 2015. Post intervention data was prospectively collected over eight weeks. Pre and post intervention SCP completion rates were compared with chi square analysis.

Results: A baseline one year review of 1124 encounters noted 23 of 90 (25%) BC survivors received SCP. Ninety-six encounters occurred during the 8 week pilot period. Sixteen (16.6%) cases met the definition of BC survivor. During the pilot period, 15 out of 16 (93.7%) survivors received the SCP and treatment summary (p &lt;0.0001). After the pilot period, 96.4% of BC survivors were seen in the BC survivorship clinic.

Conclusions: We successfully piloted the implementation of SCP for BC survivors. Our team found that using clinic visit screening and pre-identifying patients that transition into the survivorship program resulted in improvement of compliance with survivorship measures. In BC survivorship clinic we address specific survivorship issues and review SCP and treatment summary.

Citation Format: Danciu OC, Bharadwaj SN, Hoskins K. Cancer team approach for implementing survivorship care plans in the breast cancer survivorship clinic. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-10-02.

Cancer team approach for prescreening and identifying breast cancer survivors as part of survivorship care plan implementation

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Background: Recommendations from the Institute of Medicine are that cancer patients receive individualized survivorship care plan (SCP)and treatment summary.SCP includes guidelines for monitoring and maintaining health and is a communication tool shared with families and health care providers. Offering SCP and treatment summary to cancer survivors remains challenging due to time and resource limitations, inadequate reimbursement and survivor access. Methods: Survivorship starts when completing the initial treatment (surgery, chemotherapy or radiation therapy). A team of medical oncologists, nurse practitioner and patient navigator created a process of pre-screening and identifying breast cancer (BC) survivors. SCP and treatment summary were pre-populated, individualized for each patient, then finalized and discussed with the patients during their medical oncology clinic visit.Pre intervention data was retrospectively collected, including all BC cases from March 2014 to March 2015. Post intervention data was prospectively collected over eight weeks. Pre and post intervention SCP completion rates were compared with chi square analysis. Results: A baseline one year review of 1124 encounters noted 23 of 90 (25%) BC survivors received SCP. Ninety-six encounters occurred during the 8 week pilot period. Sixteen (16.6%) cases met the definition of BC survivor. During the pilot period, 15 out of 16 (93.7%) survivors received the SCP and treatment summary (p < 0.0001). Conclusions: We successfully piloted the implementation of SCP for BC survivors. Our team found that using clinic visit screening and pre-identifying patients that transition into the survivorship program resulted in improvement of compliance with survivorship measures. We plan to open a BC survivorship clinic to address survivorship issues and to review SCP and treatment summary.

Estrogen receptor-positive, progesterone receptor-negative tumors: Pathology and outcome correlations from a single-center cohort

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Background: Estrogen receptor (ER) + progesterone receptor (PR) - tumors are a distinct subset of breast cancers characterized by aggressive behavior and tamoxifen resistance in spite of being ER+. We sought to describe the characteristics of the patients treated for this type of breast cancer at a large, urban, academic center, compare them with ER+PR+ patients and evaluate the outcomes achieved with the current modern treatments and establish the predictors of worse outcomes. Methods: All patients with the diagnosis of breast cancer who underwent a biopsy at our center between January 1st, 2005 and December 31st 2010 were included into a database. We compared ER+/PR- with ER+/PR+ patients. Demographic data, comorbidities, obstetric data, pathology data, type of treatment and outcome data were collected retrospectively through extensive electronic medical records review. The study was approved by the local IRB. Standard statistical methods were used and a p value <0.05 was considered significant. Results: We found 101 ER+/PR- and 150 ER+/PR+ breast cancer patients. Baseline characteristics, pathology data, treatment and outcomes are shown in the table. Within the ER+/PR- group the degree of Ki67 expression was directly associated with recurrence rate (p 0.0039). Conclusions: ER+/PR- breast cancer is an aggressive type with high recurrence rate and mortality, that affects mainly postmenopausal women. This subtype is associated more frequently with p53 and Ki67 overexpression, and the later levels appear useful in predicting recurrence in this subtype of breast cancer. Novel treament paradigms guided by molecular studies are currently being implemented. [Table: see text]