Pre-treatment peripheral blood immunophenotyping and response to neoadjuvant chemotherapy in operable breast cancer.

BACKGROUND: Tumor immune infiltration and peripheral blood immune signatures have prognostic and predictive value in breast cancer. Whether distinct peripheral blood immune phenotypes are associated with response to neoadjuvant chemotherapy (NAC) remains understudied. METHODS: Peripheral blood mononuclear cells from 126 breast cancer patients enrolled in a prospective clinical trial (NCT02022202) were analyzed using Cytometry by time-of-flight with a panel of 29 immune cell surface protein markers. Kruskal-Wallis tests or Wilcoxon rank-sum tests were used to evaluate differences in immune cell subpopulations according to breast cancer subtype and response to NAC. RESULTS: There were 122 evaluable samples: 47 (38.5%) from patients with hormone receptor-positive, 39 (32%) triple-negative (TNBC), and 36 (29.5%) HER2-positive breast cancer. The relative abundances of pre-treatment peripheral blood T, B, myeloid, NK, and unclassified cells did not differ according to breast cancer subtype. In TNBC, higher pre-treatment myeloid cells were associated with lower pathologic complete response (pCR) rates. In hormone receptor-positive breast cancer, lower pre-treatment CD8 + naïve and CD4 + effector memory cells re-expressing CD45RA (TEMRA) T cells were associated with more extensive residual disease after NAC. In HER2 + breast cancer, the peripheral blood immune phenotype did not differ according to NAC response. CONCLUSIONS: Pre-treatment peripheral blood immune cell populations (myeloid in TNBC; CD8 + naïve T cells and CD4 + TEMRA cells in luminal breast cancer) were associated with response to NAC in early-stage TNBC and hormone receptor-positive breast cancers, but not in HER2 + breast cancer. TRIAL REGISTRATION: NCT02022202 . Registered 20 December 2013.

Patient and nursing staff perspectives on automated scalp cooling (ASC) for chemotherapy-induced alopecia in breast cancer.

PURPOSE: Automated scalp cooling (ASC) is available to patients undergoing chemotherapy for breast cancer to decrease chemotherapy-induced alopecia. This study sought to elucidate patient and chemotherapy nursing perspectives on the ASC experience. METHODS: This is a survey-based study of chemotherapy nursing staff and patients with breast cancer regarding perceived efficacy, side effects, administration, support, and overall opinions of ASC. Chemotherapy nurses across a large, multi-regional tertiary healthcare system completed a one-time survey regarding their experiences in administering ASC. Breast cancer patients who utilized ASC were surveyed along with a control group who underwent alopecia-inducing chemotherapy without ASC use for comparison. RESULTS: The majority of nursing responses reported inadequate technical support, an increased burden of administering ASC compared to other clinical duties, and that they would not recommend ASC to a family member or friend. Patients who underwent ASC reported significantly less hair loss and were significantly less likely to shave their heads or wear a wig, but this did not translate into significant differences in body image or psychosocial wellbeing responses. Time investment was the most significant burden related to ASC. CONCLUSION: Patients using ASC reported significantly less hair loss compared to those not using ASC during alopecia-inducing breast cancer chemotherapy, but this did not translate to improved body image. The majority of chemotherapy nurses reported they lacked adequate support in administering ASC and would not recommend it. Enhanced nursing support may provide a means for improving the ASC experience for both nursing staff and patients.

Integration of multiomics data shows down regulation of mismatch repair and tubulin pathways in triple-negative chemotherapy-resistant breast tumors.

BACKGROUND: Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. Patients with TNBC are primarily treated with neoadjuvant chemotherapy (NAC). The response to NAC is prognostic, with reductions in overall survival and disease-free survival rates in those patients who do not achieve a pathological complete response (pCR). Based on this premise, we hypothesized that paired analysis of primary and residual TNBC tumors following NAC could identify unique biomarkers associated with post-NAC recurrence. METHODS AND RESULTS: We investigated 24 samples from 12 non-LAR TNBC patients with paired pre- and post-NAC data, including four patients with recurrence shortly after surgery (< 24 months) and eight who remained recurrence-free (> 48 months). These tumors were collected from a prospective NAC breast cancer study (BEAUTY) conducted at the Mayo Clinic. Differential expression analysis of pre-NAC biopsies showed minimal gene expression differences between early recurrent and nonrecurrent TNBC tumors; however, post-NAC samples demonstrated significant alterations in expression patterns in response to intervention. Topological-level differences associated with early recurrence were implicated in 251 gene sets, and an independent assessment of microarray gene expression data from the 9 paired non-LAR samples available in the NAC I-SPY1 trial confirmed 56 gene sets. Within these 56 gene sets, 113 genes were observed to be differentially expressed in the I-SPY1 and BEAUTY post-NAC studies. An independent (n = 392) breast cancer dataset with relapse-free survival (RFS) data was used to refine our gene list to a 17-gene signature. A threefold cross-validation analysis of the gene signature with the combined BEAUTY and I-SPY1 data yielded an average AUC of 0.88 for six machine-learning models. Due to the limited number of studies with pre- and post-NAC TNBC tumor data, further validation of the signature is needed. CONCLUSION: Analysis of multiomics data from post-NAC TNBC chemoresistant tumors showed down regulation of mismatch repair and tubulin pathways. Additionally, we identified a 17-gene signature in TNBC associated with post-NAC recurrence enriched with down-regulated immune genes.

Association of breast cancer risk, density, and stiffness: global tissue stiffness on breast MR elastography (MRE).

PURPOSE: Quantify in vivo biomechanical tissue properties in various breast densities and in average risk and high-risk women using Magnetic Resonance Imaging (MRI)/MRE and examine the association between breast biomechanical properties and cancer risk based on patient demographics and clinical data. METHODS: Patients with average risk or high-risk of breast cancer underwent 3.0 T breast MR imaging and elastography. Breast parenchymal enhancement (BPE), density (from most recent mammogram), stiffness, elasticity, and viscosity were recorded. Within each breast density group (non-dense versus dense), stiffness, elasticity, and viscosity were compared across risk groups (average versus high). Separately for stiffness, elasticity, and viscosity, a multivariable logistic regression model was used to evaluate whether the MRE parameter predicted risk status after controlling for clinical factors. RESULTS: 50 average risk and 86 high-risk patients were included. Risk groups were similar in age, density, and menopausal status. Among patients with dense breasts, mean stiffness, elasticity, and viscosity were significantly higher in high-risk patients (N = 55) compared to average risk patients (N = 34; all p < 0.001). Stiffness remained a significant predictor of risk status (OR = 4.26, 95% CI [1.96, 9.25]) even after controlling for breast density, BPE, age, and menopausal status. Similar results were seen for elasticity and viscosity. CONCLUSION: A structurally based, quantitative biomarker of tissue stiffness obtained from MRE is associated with differences in breast cancer risk in dense breasts. Tissue stiffness could provide a novel prognostic marker to help identify high-risk women with dense breasts who would benefit from increased surveillance and/or risk reduction measures.

Phase I study of liposomal irinotecan in patients with metastatic breast cancer: findings from the expansion phase.

PURPOSE: Metastatic breast cancer (mBC) remains incurable and is associated with low survival rates. This study assessed the efficacy and safety of liposomal irinotecan in heavily pretreated patients with mBC, with or without active brain metastases (BM). METHODS: Following the dose escalation phase and determination of recommended phase 2 dose, the expansion phase of this phase I, open-label, non-randomized study, assigned adult women to cohorts based on mBC subtype: cohort 1, hormone receptor +/human epidermal growth factor receptor 2-; cohort 2, triple-negative breast cancer; or cohort 3, any mBC subtype with active BM. Patients received liposomal irinotecan 50 or 70 mg/m2 free base every 2 weeks. Here, we report secondary outcomes including best overall response (BOR), objective response rate (ORR), and treatment-emergent adverse events (TEAEs). RESULTS: For non-central nervous system (non-CNS) disease across all cohorts (intent-to-treat population, N = 29), the ORR was 34.5% (95% confidence interval: 17.94-54.33), with a BOR of partial response in 10 patients (34.5%), stable disease in five (17.2%), progressive disease in 10 (34.5%); four patients were unevaluable (13.8%). The ORR for the CNS cohort was 30.0% (95% confidence interval: 6.67-65.25) using modified Response Evaluation Criteria in Solid Tumors. Common grade 3 or higher TEAEs were diarrhea (27.6%), nausea (17.2%), fatigue (13.8%), asthenia (10.3%), and hypokalemia (10.3%). Serious treatment-related TEAEs were reported in six patients (20.7%). No treatment-related TEAEs resulted in death. CONCLUSIONS: Liposomal irinotecan monotherapy demonstrated antitumor activity in heavily pretreated patients with mBC, with or without BM. The observed safety profile was consistent with that in previous studies. CLINICAL TRIAL REGISTRATION: Trial registration ID NCT01770353.

Causes of death after breast cancer diagnosis: A US population-based analysis.

BACKGROUND: The focus on noncancer causes of death in patients with breast cancer (BC) remains superficial. The objective of the current study was to assess and quantify causes of death after BC diagnosis. METHODS: In total, 754,270 women with BC in the United States who were diagnosed during 2000 through 2015 and retrieved from the Surveillance, Epidemiology, and End Results (SEER) program were studied. Standardized mortality ratios (SMRs) for causes of death were calculated. RESULTS: Of the included patients, 183,002 (24.3%) died during the follow-up period. The greatest proportion of deaths (46.2%) occurred within 1 to 5 years after diagnosis. Most deaths occurred from BC itself or from other cancers, and the number of BC deaths decreased as more years passed after diagnosis. The most common noncancer causes of death within <10 years after diagnosis were heart diseases followed by cerebrovascular diseases. However, >10 years after diagnosis, the most common noncancer causes of death were heart diseases followed by Alzheimer disease. Patients had a statistically significant higher risk of death from chronic liver diseases within 5 to 10 years after diagnosis compared with the general population (SMR, 1.23; 95% CI, 1.09-1.38) and had statistically significant higher risks of death from Alzheimer disease (SMR, 1.21; 95% CI, 1.14-1.29) and from diseases of the heart (SMR, 1.06; 95% CI, 1.02-1.09) >10 years after diagnosis. CONCLUSIONS: Although BC remains the most common cause of death after BC diagnosis, other non-BC causes of death (mainly heart and cerebrovascular diseases) represent a significant number of deaths among patients with BC. These findings provide important insight into how BC survivors should be counselled regarding future health risks.

N083E (Alliance): long-term outcomes of patients treated in a pilot phase II study of docetaxel, carboplatin, trastuzumab, and lapatinib as adjuvant therapy for early-stage HER2-positive breast cancer.

BACKGROUND: The addition of lapatinib (L) to trastuzumab (T) was previously found to be synergistic in preclinical models and in the neoadjuvant setting. Prior to the results of the ALTTO trial, this study assessed the safety and feasibility of adding L to the standard adjuvant docetaxel, carboplatin, and trastuzumab (TCH) regimen in early-stage HER2-positive breast cancer (HER2+ BC). METHODS: In this single-arm, 2-stage, phase II study, patients with stages I-III HER2+ BC received TCH plus L at 1000 mg daily for a total of 12 months. The primary endpoint was the safety and tolerability, including the rate of diarrhea. Secondary endpoints included adverse event (AE) profile using the NCI CTCAE v3.0 and cardiac safety. RESULTS: Thirty eligible patients were enrolled. Median follow-up is 5.3 years. Diarrhea was the most common AE with 50% Grade (G)1/2 and 43% G3 diarrhea. However, it was responsive to dose reduction of L (750 mg) and institution of anti-diarrheal medications. Cardiovascular AE were infrequent and no patients experienced congestive heart failure while on treatment. CONCLUSION: TCHL was a tolerable regimen at a starting L dose of 750 mg PO daily when given concurrently with chemotherapy.

Phase 1 trial of Vismodegib and Erlotinib combination in metastatic pancreatic cancer.

BACKGROUND/OBJECTIVES: Interplay between the Hedgehog (HH) and epidermal growth factor receptor (EGFR) pathways modulating the outcome of their signaling activity have been reported in various cancers including pancreatic ductal adenocarcinoma (PDAC). Therefore, simultaneous targeting of these pathways may be clinically beneficial. This Phase I study combined HH and EGFR inhibition in metastatic PDAC patients. METHODS: Combined effects of HH and EGFR inhibition using Vismodegib and Erlotinib with or without gemcitabine in metastatic solid tumors were assessed by CT. Another cohort of patients with metastatic PDAC was evaluated by FDG-PET and tumor biopsies-derived biomarkers. RESULTS: Treatment was well tolerated with the maximum tolerated dose cohort experiencing no grade 4 toxicities though 25% experienced grade 3 adverse effects. Recommended phase II dose of Vismodegib and Erlotinib were each 150 mg daily. No tumor responses were observed although 16 patients achieved stable disease for 2-7 cycles. Paired biopsy analysis before and after first cycle of therapy in PDAC patients showed reduced GLI1 mRNA, phospho-GLI1 and associated HH target genes in all cases. However, only half of the cases showed reduced levels of desmoplasia or changes in fibroblast markers. Most patients had decreased phospho-EGFR levels. CONCLUSIONS: Vismodegib and Erlotinib combination was well-tolerated although overall outcome in patients with metastatic PDAC was not significantly impacted by combination treatment. Biomarker analysis suggests direct targets inhibition without significantly affecting the stromal compartment. These findings conflict with pre-clinical mouse models, and thus warrant further investigation into how upstream inhibition of these pathways is circumvented in PDAC.

Understanding American Indian Perceptions Toward Radiation Therapy.

Many American Indian (AI) and Alaska native (AN) patients do not complete guideline-concordant cancer care for the 4 most common cancers. Our aim was to better understand AI/AN attitudes toward radiation therapy (RT). Patients eligible for this survey study were AI/AN patients with cancer at the Phoenix Indian Medical Center who either received previous RT or were recommended to receive RT. An 18-item questionnaire was administered to each of the 50 participants from October 1, 2018, through February 15, 2019. Willingness to travel for RT was compared to respondent characteristics, concerns regarding RT, and obstacles to obtain RT. Duration of RT was important to 78% of patients: 24% would consider traveling 25 miles or more for a standard course, and 48% would travel that distance for a shorter course (P < .001). The top-ranked barriers to RT were transportation, cost of treatment, and insurance compatibility. The top-ranked concerns about RT were adverse effects, cost of treatment, and fear of RT. Concerns about adverse effects were associated with the radiation team's inability to explain the treatment (P = .05). Transportation concerns were significantly associated with accessibility (P = .02), communication with the RT team (P = .02), and fear of RT (P = .04). AI/AN patients are concerned about the adverse effects of RT and the logistics of treatment, particularly costs, transportation, and insurance compatibility. Use of culturally specific education and hypofractionation regimens may increase acceptance of RT for AI/AN patients with cancer, and this hypothesis will be tested in a future educational intervention-based study.

Gauging the efficacy of neoadjuvant endocrine therapy in breast cancer patients with known axillary disease.

BACKGROUND AND OBJECTIVES: Neoadjuvant endocrine therapy (NET) for ER+ breast cancer can downstage primary tumors. We evaluated NET efficacy in node-positive patients. METHODS: Node-positive patients undergoing NET for ER+ breast cancer from 2012 to 2019 were reviewed. Primary endpoints included rates of axillary lymphadenectomy (ALND), pathologic complete response (pCR), and final nodal staging. RESULTS: Thirty-nine patients were included. Before NET, all were clinically node-positive (cN1 = 36, 94%; cN2 = 2, 5%; cN3 = 1, 3%; Stage II = 23, 59%, Stage III = 16, 41%). After NET, nine (23%) had clinically persistent axillary disease necessitating ALND. The remaining 30 (77%) underwent sentinel lymph node biopsy (SLNB). Of these, 25 (83%) were SLNB+ on frozen section, undergoing immediate ALND. Five patients were negative on frozen section: one had a confirmed axillary pCR, and four had residual nodal disease on permanent pathology. One underwent delayed ALND, and for the remaining three patients, decision was made to forgo ALND. Final overall axillary staging was: N0 (pCR) = 1, 3%, pN1mic = 1, 3%, pN1 = 20, 51%, pN2 = 12, 30%, pN3 = 5, 13%; Stage II = 16, 41%, Stage III = 23, 59%. CONCLUSIONS: While NET is reported to downstage primary tumors, downstaging of the axilla was unsuccessful in the majority of patients.

Depomedroxyprogesterone acetate therapy for hot flashes in survivors of breast cancer: no unfavorable impact on recurrence and survival.

PURPOSE: Survivors of estrogen receptor-expressing breast cancer generally do not receive estrogen-based therapy for menopausal symptoms due to concern for provoking recurrence of disease. Single-dose depomedroxyprogesterone acetate has been shown to be among the most effective non-estrogen strategies for treatment of menopausal hot flashes, but long-term evidence for safety in survivors is lacking. METHODS: We conducted an institutional review board approved, retrospective, case-control cohort study at a tertiary, academic referral center. Patients with estrogen receptor-expressing early-stage operable breast cancer who received depomedroxyprogesterone acetate for hot flashes between January 2005 and December 2012 were identified. We confirmed 75 patients who met strict inclusion criteria who were matched 1:1 with controls for age, stage of disease, HER2 status, and year of diagnosis. Overall survival, loco-regional recurrence-free survival, and progression-free survival assessments for cases were compared with controls. RESULTS: Median follow-up duration was 68.4 months in cases and 57.6 months in controls. Estimated local-regional recurrence-free survival at 10 years was 97% (95% CI, 92-100%) in cases and 98% (95% CI, 95-100%) in controls. Estimated progression-free survival at 10 years was 89% (95% CI, 80-100%) in cases and 83% (95% CI, 73-95) in controls. The majority (75%) of case patients experienced satisfactory relief of hot flashes from depomedroxyprogesterone injection. DISCUSSION: In this retrospective case-control study, we were unable to identify a detrimental effect of depomedroxyprogesterone acetate therapy for hot flashes in survivors of estrogen receptor-expressing breast cancer. Depomedroxyprogesterone acetate may be acceptable for management of hot flashes in this population.

Adaptive Randomization of Neratinib in Early Breast Cancer.

BACKGROUND: The heterogeneity of breast cancer makes identifying effective therapies challenging. The I-SPY 2 trial, a multicenter, adaptive phase 2 trial of neoadjuvant therapy for high-risk clinical stage II or III breast cancer, evaluated multiple new agents added to standard chemotherapy to assess the effects on rates of pathological complete response (i.e., absence of residual cancer in the breast or lymph nodes at the time of surgery). METHODS: We used adaptive randomization to compare standard neoadjuvant chemotherapy plus the tyrosine kinase inhibitor neratinib with control. Eligible women were categorized according to eight biomarker subtypes on the basis of human epidermal growth factor receptor 2 (HER2) status, hormone-receptor status, and risk according to a 70-gene profile. Neratinib was evaluated against control with regard to 10 biomarker signatures (prospectively defined combinations of subtypes). The primary end point was pathological complete response. Volume changes on serial magnetic resonance imaging were used to assess the likelihood of such a response in each patient. Adaptive assignment to experimental groups within each disease subtype was based on Bayesian probabilities of the superiority of the treatment over control. Enrollment in the experimental group was stopped when the 85% Bayesian predictive probability of success in a confirmatory phase 3 trial of neoadjuvant therapy reached a prespecified threshold for any biomarker signature ("graduation"). Enrollment was stopped for futility if the probability fell to below 10% for every biomarker signature. RESULTS: Neratinib reached the prespecified efficacy threshold with regard to the HER2-positive, hormone-receptor-negative signature. Among patients with HER2-positive, hormone-receptor-negative cancer, the mean estimated rate of pathological complete response was 56% (95% Bayesian probability interval [PI], 37 to 73%) among 115 patients in the neratinib group, as compared with 33% among 78 controls (95% PI, 11 to 54%). The final predictive probability of success in phase 3 testing was 79%. CONCLUSIONS: Neratinib added to standard therapy was highly likely to result in higher rates of pathological complete response than standard chemotherapy with trastuzumab among patients with HER2-positive, hormone-receptor-negative breast cancer. (Funded by QuantumLeap Healthcare Collaborative and others; I-SPY 2 TRIAL ClinicalTrials.gov number, NCT01042379.).

Adaptive Randomization of Veliparib-Carboplatin Treatment in Breast Cancer.

BACKGROUND: The genetic and clinical heterogeneity of breast cancer makes the identification of effective therapies challenging. We designed I-SPY 2, a phase 2, multicenter, adaptively randomized trial to screen multiple experimental regimens in combination with standard neoadjuvant chemotherapy for breast cancer. The goal is to match experimental regimens with responding cancer subtypes. We report results for veliparib, a poly(ADP-ribose) polymerase (PARP) inhibitor, combined with carboplatin. METHODS: In this ongoing trial, women are eligible for participation if they have stage II or III breast cancer with a tumor 2.5 cm or larger in diameter; cancers are categorized into eight biomarker subtypes on the basis of status with regard to human epidermal growth factor receptor 2 (HER2), hormone receptors, and a 70-gene assay. Patients undergo adaptive randomization within each biomarker subtype to receive regimens that have better performance than the standard therapy. Regimens are evaluated within 10 biomarker signatures (i.e., prospectively defined combinations of biomarker subtypes). Veliparib-carboplatin plus standard therapy was considered for HER2-negative tumors and was therefore evaluated in 3 signatures. The primary end point is pathological complete response. Tumor volume changes measured by magnetic resonance imaging during treatment are used to predict whether a patient will have a pathological complete response. Regimens move on from phase 2 if and when they have a high Bayesian predictive probability of success in a subsequent phase 3 neoadjuvant trial within the biomarker signature in which they performed well. RESULTS: With regard to triple-negative breast cancer, veliparib-carboplatin had an 88% predicted probability of success in a phase 3 trial. A total of 72 patients were randomly assigned to receive veliparib-carboplatin, and 44 patients were concurrently assigned to receive control therapy; at the completion of chemotherapy, the estimated rates of pathological complete response in the triple-negative population were 51% (95% Bayesian probability interval [PI], 36 to 66%) in the veliparib-carboplatin group versus 26% (95% PI, 9 to 43%) in the control group. The toxicity of veliparib-carboplatin was greater than that of the control. CONCLUSIONS: The process used in our trial showed that veliparib-carboplatin added to standard therapy resulted in higher rates of pathological complete response than standard therapy alone specifically in triple-negative breast cancer. (Funded by the QuantumLeap Healthcare Collaborative and others; I-SPY 2 TRIAL ClinicalTrials.gov number, NCT01042379.).

Contrast-Enhanced Spectral Mammography is Comparable to MRI in the Assessment of Residual Breast Cancer Following Neoadjuvant Systemic Therapy.

PURPOSE: To evaluate the performance of contrast-enhanced spectral mammography (CESM) compared to MRI in the assessment of tumor response in breast cancer patients undergoing neoadjuvant systemic therapy (NST). METHODS: The institutional review board approved this study. From September 2014 to June 2017, we identified patients with pathologically confirmed invasive breast cancer who underwent NST. All patients had both CESM and MRI performed pre- and post-NST with pathological assessment after surgical management. Size of residual malignancy on post-NST CESM and MRI was compared with surgical pathology. Lin concordance and Pearson correlation coefficient were used to assess agreement. Bland-Altman plots were used to visualize the differences between tumor size on imaging and pathology. RESULTS: Sixty-five patients were identified. Mean age was 52.7 (range 30-76) years. Type of NST included chemotherapy in 53 (82%) and endocrine therapy in 12 (18%). Mean tumor size after NST was 14.6 (range 0-105) mm for CESM and 14.2 mm (range 0-75 mm) for MRI compared with 19.6 (range 0-100) mm on final surgical pathology. Equivalence tests demonstrated that mean tumor size measured by CESM (p = 0.009) or by MRI (p = 0.01) was equivalent to the mean tumor size measured by pathology within - 1 and 1-cm range. Comparing CESM versus MRI for assessment of complete response, the sensitivity was 95% versus 95%, specificity 66.7% versus 68.9%, positive predictive value 55.9% versus 57.6%, and negative predictive value 96.7% versus 96.9% respectively. CONCLUSIONS: CESM was comparable to MRI in assessing residual malignancy after completion of NST.

The Future of Contrast-Enhanced Mammography.

OBJECTIVE: The purpose of this article is to discuss facilitators of and barriers to future implementation of contrast-enhanced mammography (CEM) in the United States. CONCLUSION: CEM provides low-energy 2D mammographic images analogous to digital mammography and contrast-enhanced recombined images that allow assessment of neovascularity similar to that offered by MRI. The utilization of CEM in the United States is currently low but could increase rapidly given the many potential indications for its clinical use.

Breast MRI phenotype and background parenchymal enhancement may predict tumor response to neoadjuvant endocrine therapy.

Neoadjuvant endocrine therapy (NET) is increasingly used for the treatment of estrogen receptor positive, HER2 negative breast cancer. We evaluated whether MRI phenotype and background parenchymal enhancement (BPE) can predict response to NET. Patients with localized breast cancer treated with NET and had a pre-treatment breast MRI were identified. Baseline MRI phenotype and BPE was interpreted by a single radiologist blinded to the results of systemic therapy. Response was defined as stable disease or reduction in tumor size on clinical and/or ultrasound examination. Of the 21 patients identified, 17 were responders; all patients with minimal/mild BPE had a response compared to 5/9 (56%) patients with moderate/marked BPE (P = 0.02). All four nonresponders had moderate/marked BPE as compared to 5/17 (29%) responders (P = 0.02). This pilot study suggests that minimal/mild BPE may be predictive of a positive response to NET. A higher degree of background enhancement was significantly predictive of negative response to NET.

Serum thymidine kinase 1 activity as a pharmacodynamic marker of cyclin-dependent kinase 4/6 inhibition in patients with early-stage breast cancer receiving neoadjuvant palbociclib.

BACKGROUND: Thymidine kinase 1 (TK1) is a cell cycle-regulated enzyme with peak expression in the S phase during DNA synthesis, and it is an attractive biomarker of cell proliferation. Serum TK1 activity has demonstrated prognostic value in patients with early-stage breast cancer. Because cyclin-dependent kinase 4/6 (CDK4/6) inhibitors prevent G1/S transition, we hypothesized that serum TK1 could be a biomarker for CDK4/6 inhibitors. We examined the drug-induced change in serum TK1 as well as its correlation with change in tumor Ki-67 levels in patients enrolled in the NeoPalAna trial (ClinicalTrials.gov identifier NCT01723774). METHODS: Patients with clinical stage II/III estrogen receptor-positive (ER+)/HER2-negative breast cancer enrolled in the NeoPalAna trial received an initial 4 weeks of anastrozole, followed by palbociclib on cycle 1, day 1 (C1D1) for four 28-day cycles, unless C1D15 tumor Ki-67 was > 10%, in which case patients went off study owing to inadequate response. Surgery occurred following 3-5 weeks of washout from the last dose of palbociclib, except in eight patients who received palbociclib (cycle 5) continuously until surgery. Serum TK1 activity was determined at baseline, C1D1, C1D15, and time of surgery, and we found that it was correlated with tumor Ki-67 and TK1 messenger RNA (mRNA) levels. RESULTS: Despite a significant drop in tumor Ki-67 with anastrozole monotherapy, there was no statistically significant change in TK1 activity. However, a striking reduction in TK1 activity was observed 2 weeks after initiation of palbociclib (C1D15), which then rose significantly with palbociclib washout. At C1D15, TK1 activity was below the detection limit (<20 DiviTum units per liter Du/L) in 92% of patients, indicating a profound effect of palbociclib. There was high concordance, at 89.8% (95% CI: 79.2% - 96.2%), between changes in serum TK1 and tumor Ki-67 in the same direction from C1D1 to C1D15 and from C1D15 to surgery time points. The sensitivity and specificity for the tumor Ki-67-based response by palbociclib-induced decrease in serum TK1 were 94.1% (95% CI 86.2% - 100%) and 84% (95% CI 69.6% -98.4%), respectively. The κ-statistic was 0.76 (p < 0.001) between TK1 and Ki-67, indicating substantial agreement. CONCLUSIONS: Serum TK1 activity is a promising pharmacodynamic marker of palbociclib in ER+ breast cancer, and its value in predicting response to CDK4/6 inhibitors warrants further investigation. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01723774. Registered on 6 November 2012.

Establishing and characterizing patient-derived xenografts using pre-chemotherapy percutaneous biopsy and post-chemotherapy surgical samples from a prospective neoadjuvant breast cancer study.

BACKGROUND: Patient-derived xenografts (PDXs) are increasingly used in cancer research as a tool to inform cancer biology and drug response. Most available breast cancer PDXs have been generated in the metastatic setting. However, in the setting of operable breast cancer, PDX models both sensitive and resistant to chemotherapy are needed for drug development and prospective data are lacking regarding the clinical and molecular characteristics associated with PDX take rate in this setting. METHODS: The Breast Cancer Genome Guided Therapy Study (BEAUTY) is a prospective neoadjuvant chemotherapy (NAC) trial of stage I-III breast cancer patients treated with neoadjuvant weekly taxane+/-trastuzumab followed by anthracycline-based chemotherapy. Using percutaneous tumor biopsies (PTB), we established and characterized PDXs from both primary (untreated) and residual (treated) tumors. Tumor take rate was defined as percent of patients with the development of at least one stably transplantable (passed at least for four generations) xenograft that was pathologically confirmed as breast cancer. RESULTS: Baseline PTB samples from 113 women were implanted with an overall take rate of 27.4% (31/113). By clinical subtype, the take rate was 51.3% (20/39) in triple negative (TN) breast cancer, 26.5% (9/34) in HER2+, 5.0% (2/40) in luminal B and 0% (0/3) in luminal A. The take rate for those with pCR did not differ from those with residual disease in TN (p = 0.999) and HER2+ (p = 0.2401) tumors. The xenografts from 28 of these 31 patients were such that at least one of the xenografts generated had the same molecular subtype as the patient. Among the 35 patients with residual tumor after NAC adequate for implantation, the take rate was 17.1%. PDX response to paclitaxel mirrored the patients' clinical response in all eight PDX tested. CONCLUSIONS: The generation of PDX models both sensitive and resistant to standard NAC is feasible and these models exhibit similar biological and drug response characteristics as the patients' primary tumors. Taken together, these models may be useful for biomarker discovery and future drug development.

Survival benefit needed to undergo chemotherapy: Patient and physician preferences.

BACKGROUND: Published studies have suggested that most patients with early stage breast cancer are willing, for modest survival benefits, to receive 6 months of adjuvant cyclophosphamide, methotrexate, and 5-fluorouracil, an older regimen that is used infrequently today. We examined preferences regarding the survival benefit needed to justify 6 months of a contemporary chemotherapy regimen. METHODS: The Eastern Cooperative Oncology Group Protocol 5103 was a phase 3 trial that randomized breast cancer patients to receive standard adjuvant doxorubicin, cyclophosphamide, and paclitaxel with either bevacizumab or placebo. Serial surveys to assess quality of life were administered to patients enrolled between January 1, 2010, and June 8, 2010. Survival benefit needed to justify 6 months of chemotherapy by patients was collected at the 18-month assessment. A parallel survey was sent to physicians who had enrolled patients in the study. RESULTS: Of 519 patients who had not withdrawn at a time point earlier than 18 months, 87.8% responded to this survey. A total of 175 physicians participated. We found considerable variation in patient preferences, particularly for modest survival benefits: for 2 months of benefit, 57% would consider 6 months of chemotherapy, whereas 96% of patients would consider 6 months of chemotherapy for 24 months. Race and education were associated with the choices. Physicians who responded were less likely to accept chemotherapy for modest benefit. CONCLUSIONS: Among patients who received contemporary adjuvant chemotherapy in a randomized controlled trial, we found substantial variation in preferences regarding benefits that justified undergoing chemotherapy. Differences between patients' and physicians' choices were also apparent. Eliciting preferences regarding risks and benefits of adjuvant chemotherapy is critical. Cancer 2017;123:2821-28. © 2017 American Cancer Society.

Does biomarker information impact breast cancer patients' preferences and physician recommendation for adjuvant chemotherapy?

PURPOSE: This study aimed to examine how biomarker information would impact patients' preferences and physicians' recommendations for adjuvant breast cancer therapy. METHODS: At the 18-month follow-up, participants in a large, double-blind randomized controlled trial of adjuvant chemotherapy with bevacizumab or placebo (E5103) were surveyed about their preferred treatment (either chemotherapy A alone or chemotherapy A+B) in two hypothetical scenarios: (1) without biomarker information; and (2) after learning that they tested positive for a "B-receptor" which modestly increased both the benefit and toxicity expected with chemotherapy A+B. We performed a cross-sectional analysis of the prospectively collected survey data and used the McNemar's test to examine changes in treatment preferences. A one-time survey of clinical investigators who enrolled patients on the trial evaluated physician recommendations in response to the same biomarker information. RESULTS: 439 patients completed both scenarios on 18-month survey. Most participants preferred A+B in both scenario 1 and 2 (77 and 76% respectively). The increase in benefit and toxicity associated with the positive biomarker information in scenario 2 led 60/439 (14%) of patients to switch their treatment preference. The corresponding physician survey revealed that most physicians chose regimen A+B in scenario 1 (77%), and moreso after the biomarker information was available in scenario 2 (84%). CONCLUSIONS: Information about a positive biomarker indicating increased benefit and toxicity from additional chemotherapy did not change many participants' preferred treatment. The majority preferred the most effective course in both scenarios. Similarly, most investigators discounted increased toxicity and valued increased benefit. Parent Trial Registration: NCT00433511.