Citations

Abstract Background: Based upon the association between pathologic response and disease free survival, the neoadjuvant setting is increasingly being used for drug development. NGS has identified unique and recurrent genetic alterations in breast cancer (BC) that are potentially targetable; however, the clinical implications are mostly unknown. We developed a prospective neoadjuvant study (BEAUTY) in high risk BC patients (pts) using weekly T followed by anthracycline-based chemo wherein percutaneous tumor biopsies (PTB) are obtained before/during/after chemo for NGS and PDX. Our goal is to identify novel biomarkers/pathways and develop PDX to test new therapeutic approaches. Methods: Pts underwent PTB at baseline and after 12 wks of T. Response to T was defined based upon 12 week Ki-67: responder (<15%) vs non-responder (≥15%). Pts with histologic response and absence of invasive BC at 12 wks were classified as responders. NGS was performed using PTB/blood DNA (exome) and PTB (RNA seq). MRI response was classified using RECIST criteria. NGS data were used to identify somatic copy number variants (cnvs) and expressed single nucleotide variants (eSNVs). Non-SCID mice (estrogen supplemented) were implanted ≤ 30 minutes with PTB samples. Results: Of the first 78 pts, 44 have completed T. Here we focus on 18 pts with either triple negative or luminal B BC. Clinical characteristics according to Ki-67 response are shown in Table 1. Comparison of genomic alterations in BEAUTY pts with TCGA identified a greater overlap with copy number gains (73%) compared to deletions (40%), along with similar observations of mutations in TP53, PTEN, RYR2, and AKT1 genes. Association analysis of CNVs and eSNVs between responders/non-responders identified 33 genes (predominantly located in chromosomes 1, 8, 13) and 580 eSNVs (corresponding to 497 genes) with a p < 0.05. Differential gene expression (DGE) analysis of responders/non-responders identified 198 genes with a p-value < 0.05. Integrated analysis of 539 genes (CNVs, eSNVs and DGE) identified pathways such as TGF-beta, Jak-Stat, WNT and NOTCH signalling. PDX take rate was 44% [triple negative (6/10); Luminal B (2/8)]. PDX growth rate was significantly associated with clinical baseline Ki-67 (p = 0.00014). Conclusion: This is the first prospective study to demonstrate the feasibility of using PTB to obtain both NGS data and PDX in the neoadjuvant setting. PDX take rate is associated with BC subtype and baseline Ki-67. Studies are ongoing to 1) validate genes/pathways associated with treatment response in subsequent BEAUTY pts; 2) genomically characterize and assess PDX in vivo response to T and 3) Use NGS data to prioritize new drugs/drug combinations in PDX. Funded by Mayo Clinic Center for Individualized Medicine and MC Cancer Center. Clinical CharacteristicsOverallResponders: 12 week Ki-67 < 15% (n = 9)Non-Responders: 12 week Ki-67 ≥ 15% (n = 9)Median Age495345T stage T2/T314 (78%)7 (78%)7 (78%)Node Positive8 (44%)4 (44%)4 (44%)Triple negative10 (56%)6 (67%)4 (44%)Luminal B8 (44%)3 (33%)5 (56%)Ki-67 after 12 Weeks of T Median 5% (0-11%)Median 35% (17-60%)Complete/Partial MRI Response after T 6 (67%)2 (22%) Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-08-10.

BACKGROUNDIncreased soluble human epidermal growth factor receptor 2 (sHER2) is an indicator of a poor prognosis in HER2‐positive metastatic breast cancer. In this study, the authors evaluated levels of sHER2 during treatment and at the time of disease recurrence in the adjuvant North Central Cancer Treatment Group N9831 clinical trial.METHODSThe objectives were to describe sHER2 levels during treatment and at the time of recurrence in patients who were randomized to treatment arms A (standard chemotherapy), B (standard chemotherapy with sequential trastuzumab), and C (standard chemotherapy with concurrent trastuzumab). Baseline samples were available from 2318 patients, serial samples were available from 105 patients, and recurrence samples were available from 124 patients. The cutoff sHER2 value for the assay was 15 ng/mL. Statistical methods included repeated measures linear models, Wilcoxon rank‐sum tests, and Cox regression models.RESULTSThere were differences between groups in terms of age, menopausal status, and hormone receptor status. Within treatment arms A, B, and C, patients who had baseline sHER2 levels ≥15 ng/mL had worse disease‐free survival than patients who had baseline sHER2 levels <15 ng/mL (arm A: hazard ratio, 1.81; P = .0014; arm B: hazard ratio, 2.08; P = .0015; arm C: hazard ratio, 1.96; P = .01). Among the 124 patients who experienced disease recurrence, sHER2 levels increased from baseline to the time of recurrence in arms A and B but remained unchanged in arm C. Patients who had recurrence sHER2 levels ≥15 ng/mL had a shorter survival after recurrence with a 3‐year overall survival rate of 51% compared with 77% for those who had recurrence sHER2 levels <15 ng/mL (hazard ratio, 2.36; 95% confidence interval, 1.19‐4.70; P = .01).CONCLUSIONSIn patients with early stage, HER2‐positive breast cancer, a high baseline sHER2 level was identified as a prognostic marker associated with shorter disease‐free survival, and a high sHER2 level at recurrence was predictive of shorter survival. Cancer 2013;119:2675–2682. © 2013 American Cancer Society.

BACKGROUNDData suggest that weight, and specifically body mass index (BMI), plays a role in breast cancer development and outcome. The authors hypothesized that there would be a correlation between BMI and clinical outcome in patients with early stage, human epidermal receptor 2 (HER2)‐positive breast cancer enrolled in the N9831 adjuvant trial.METHODSPatients were grouped according to baseline BMI as follows: normal (BMI <25 kg/m2), overweight (BMI ≥25 kg/m2 and <30 kg/m2), and obese (BMI ≥30 kg/m2). Disease‐free survival (DFS) was estimated using the Kaplan‐Meier method. Comparisons between treatment arms A, B, and C (chemotherapy with or without trastuzumab) were performed using a stratified Cox proportional hazards model.RESULTSAnalysis was completed on 3017 eligible patients. Obese patients were more likely to be older and postmenopausal (P < .0001 for both), to have larger tumors (P = .002), and to have positive lymph nodes (P = .004). In the pooled analysis cohort, differences in DFS among the BMI groups were statistically significant (5‐year DFS rate: 82.5%, 78.6%, and 78.5% for normal weight, overweight, and obese women, respectively; log‐rank P = .02). The adjusted hazard ratio comparing the DFS of overweight women with the DFS of normal women was 1.30 (95% confidence interval, 1.06‐1.61); and, comparing the DFS of obese women with the DFS normal women, the adjusted hazard ratio was 1.31 (95% confidence interval, 1.07‐1.59). There were no statistically significant differences in DFS by weight group for women within any trial arm.CONCLUSIONSPatients with early stage, HER2‐positive breast cancer and normal BMI had a better 5‐year DFS compared with overweight and obese women. The current results indicated that adjuvant trastuzumab improves clinical outcome regardless of BMI. Cancer 2013;119:2447‐2454. © 2013 American Cancer Society.

Abstract Background Obesity, as defined by body mass index (BMI), has been associated with increased recurrence rate, shorter DFS and increased death rates due to breast cancer (BC). Most of the studies to date have examined the relationship of BMI and DFS in patients with hormone receptor positive disease. To our knowledge, BMI and its relationship with outcome in early stage HER2 positive breast cancer has not previously been examined. The N9831 is a large phase III trial testing the role of trastuzumab in the adjuvant setting of high risk patients with early stage HER2+ BC. We hypothesized that the occurrence of overweight and obesity may correlate with outcome. Methods: This analysis presents BMI and its relation to tumor characteristics and DFS in patients (pts) enrolled in the N9831 clinical trial. Pts were categorized as normal weight, overweight or obese using the WHO BMI classification parameters of &lt; 25%, 25–29% and ≥ 30% respectively. For patient characteristics, patients were grouped into non-obese (BMI&lt; 30) and obese (≥ 30) cohorts. DFS was estimated by the Kaplan-Meier method. Comparisons between arms A (chemotherapy alone), B (chemotherapy plus sequential trastuzumab) and C (chemotherapy plus concurrent trastuzumab) were performed using the Cox proportional hazards model, stratified by BMI. Results: Analysis was completed on 3,017 eligible pts. Obese pts were more likely to be older and postmenopausal (p&lt;0.0001 for both). There was no significant association between BMI and ER/PR status (p=0.07) or histologic tumor grade (p=0.33). Obese pts were found to have significantly larger tumors ≥ 2 cm (p=0.002) and more positive lymph nodes (p=0.02). There was no significant difference in DFS within each intrinsic arm (A, B and C) between the obese and non-obese pts at 3, 5 or 7 yrs of follow up. However, pts in the non-obese group had significantly improved DFS in arm B and C compared to arm A (p=0.001 and p&lt;0.0001 respectively). Also obese pts in arm C had significantly improved DFS compared to obese pts in arm A (p=0.008). There was a trend of improved DFS in the obese group in arm B compared to arm A, but this was not statistically significant (p=0.09). Pts in the normal weight and overweight groups did significantly better in arm B (p=0.02 for both) and arm C (p=0.01 and p=0.002 respectively) compared to arm A. Conclusions: This analysis of data from the N9831 study confirms that obese pts with early stage HER2+ tumors have worse clinical outcome than pts with BMI &lt; 30%. Adjuvant trastuzumab improved clinical outcome regardless of BMI. This study supports weight loss intervention for obese women with early stage HER2+ BC. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-12-02.

Abstract Background Tumors that are negative for estrogen and progesterone receptors and do not over express HER2 are referred as “triple negative” breast cancer (TNBC). These tumors are characterized by unique molecular profiles on gene expression arrays, aggressive behavior with a high recurrence rate, an increased risk of visceral metastases, poor prognosis and lack of targeted therapies. Brostallicin is a novel synthetic compound from the class of DNA minor groove binding (MGB) anti-cancer agents. It retains activity in cancer cells resistant to alkylating agents, topoisomerase I inhibitors and is fully active against DNA-mismatch repair deficient tumor cells. Cells expressing relatively high glutathione/glutathione S-transferase (GSH/GST) levels are more susceptible to brostallicin antitumor efficacy. Cisplatin administration increases expression of GST in tumor cells leading to an increased anti-tumor efficacy of brostallicin. Trial design: Single-stage phase II study — based on the effects of cisplatin on GSH/GST levels in preclinical models, the most reasonable sequence to explore was cisplatin on Day 1 followed by brostallicin on Day 2 repeated every 21 days. Eligibility criteria: Women or men ≥18 years of age with confirmed adenocarcinoma of the breast with clinical evidence of measurable metastatic disease and triple negative subtype according to current ASCO CAP guidelines [ER/PR ≤1%; HER2 negative), who received 0–4 prior chemotherapy regimens in the metastatic setting; with adequate hematologic, renal and hepatic functions; and no active CNS metastases. Aims: To study the efficacy of the novel drug, brostallicin, as well as to serve as proof of concept of its mechanism of action in TNBC. The primary endpoint is to evaluate clinical efficacy of the combination of brostallicin and cisplatin in the treatment of patients with metastatic TNBC, as measured by progression-free survival (PFS) at 3 months with 89% power (0.10 significance level) to detect an absolute difference of 20%. Secondary endpoints include ORR by RECIST, duration of response, 6-month PFS, overall survival (OS) and adverse event profile. Tertiary endpoints include assessment of 1) GSH levels prior to the administration of cisplatin and of brostallicin; and 2) the prevalence of BCRA-1 mutation by IHC in the primary or metastatic tumor. Statistical methods: The largest 3-month PFS proportion where the proposed treatment regimen would be considered ineffective in this population was estimated at 35% based on the median PFS of 60 days in patients with metastatic TNBC enrolled in the N0234 trial (erlotinib and gemcitabine as 1st/2nd line), and the smallest 3-month PFS success proportion that may warrant subsequent studies with the proposed regimen in this patient population was estimated at 55%. The interim analysis will be reported when the 20th eligible patient has been followed for 3 months. Present accrual and target accrual: 21 patients have been accrued at the time of abstract submission (June 2011). Target accrual is 42 evaluable patients. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT3-01-14.

There is an ongoing need for development of new chemotherapeutic regimens for metastatic breast cancer [mBC], especially when tumors lack therapeutic targets such as the estrogen or progesterone receptor [ER/PR], or the human epidermal growth factor receptor-2 [HER2]. Capecitabine is an orally bioavailable fluoropyrimidine approved for monotherapy in mBC, and bevacizumab is a monoclonal antibody targeting vascular endothelial growth factor which has shown to be active in mBC and tolerable in combination with other chemotherapeutics. The combination of these two agents has been explored in multiple phase II and III clinical studies, with improvements in progression-free survival and overall response rates noted as compared to capecitabine monotherapy. However, the use of bevacizumab in combination with capecitabine and other chemotherapy agents for mBC remains beset with controversy due to safety concerns, cost issues, and pending regulatory decisions.

Purpose NCCTG (North Central Cancer Treatment Group) N9831 is the only randomized phase III trial evaluating trastuzumab added sequentially or used concurrently with chemotherapy in resected stages I to III invasive human epidermal growth factor receptor 2–positive breast cancer. Patients and Methods Patients received doxorubicin and cyclophosphamide every 3 weeks for four cycles, followed by paclitaxel weekly for 12 weeks (arm A), paclitaxel plus sequential trastuzumab weekly for 52 weeks (arm B), or paclitaxel plus concurrent trastuzumab for 12 weeks followed by trastuzumab for 40 weeks (arm C). The primary end point was disease-free survival (DFS). Results Comparison of arm A (n = 1,087) and arm B (n = 1,097), with 6-year median follow-up and 390 events, revealed 5-year DFS rates of 71.8% and 80.1%, respectively. DFS was significantly increased with trastuzumab added sequentially to paclitaxel (log-rank P < .001; arm B/arm A hazard ratio [HR], 0.69; 95% CI, 0.57 to 0.85). Comparison of arm B (n = 954) and arm C (n = 949), with 6-year median follow-up and 313 events, revealed 5-year DFS rates of 80.1% and 84.4%, respectively. There was an increase in DFS with concurrent trastuzumab and paclitaxel relative to sequential administration (arm C/arm B HR, 0.77; 99.9% CI, 0.53 to 1.11), but the P value (.02) did not cross the prespecified O'Brien-Fleming boundary (.00116) for the interim analysis. Conclusion DFS was significantly improved with 52 weeks of trastuzumab added to adjuvant chemotherapy. On the basis of a positive risk-benefit ratio, we recommend that trastuzumab be incorporated into a concurrent regimen with taxane chemotherapy as an important standard-of-care treatment alternative to a sequential regimen.

Abstract Purpose: To investigate the associations between baseline and posttreatment circulating tumor cell (CTC) gene expression and outcome of patients enrolled in four North Central Cancer Treatment Group metastatic breast cancer (MBC) trials in which specimens were shipped (at 4°C) from community-based sites to a reference laboratory (Mayo Clinic, Rochester, MN). Experimental Design: Blood was collected at treating sites from MBC patients before (baseline), during, and at the end of treatment with erlotinib + gemcitabine (N0234), sorafenib (N0336), irinotecan + cetuximab (N0436), or paclitaxel-poliglumex + capecitabine (N0437). CTCs from 10 mL of EDTA blood were enriched with CD45 depletion, 24 to 30 hours postblood collection. Reverse transcription/quantitative PCR was used to determine cytokeratin-19 (CK19) and mammaglobin (MGB1) mRNA levels in CTCs from up to 13 (N0234), 16 (N0336), 18 (N0436), and 39 (N0437) patients. The gene expressions were normalized to β2-microglobulin and calibrated to healthy blood using the 2–ΔΔCq algorithm; positivity was defined as 2 or more. Results: CK19+mRNA cells were detected in 56% to 75% and MGB1+mRNA cells in 23% to 38% of 86 patients at baseline. CK19+mRNA cells were detected in 30% to 67% and MGB1+mRNA cells in 14% to 64% of 110 postbaseline serial samples. The presence of baseline CK19+mRNA cells (P = 0.01) but not MGB1+mRNA cells (P = 0.14) was significantly associated with shorter overall survival. A decrease in MGB1+mRNA levels (baseline-week 8) seemed to be associated with clinical response (P = 0.05). Conclusions: CTC gene expression analysis conducted by a reference laboratory is feasible when blood is collected from treating sites and processed 24 to 30 hours postcollection. The presence of baseline CK19+mRNA CTCs was associated with poor prognosis; a decrease in MGB1+mRNA CTCs may help predict response to therapy of MBC patients. Clin Cancer Res; 17(22); 7183–93. ©2011 AACR.

Abstract Background: Microtubules are crucial for spindle formation during mitosis and for cellular proliferation. The antineoplastic effect of paclitaxel is mainly related to its ability to bind the beta subunit of tubulin, thus preventing tubulin chain depolarization and inducing apoptosis. Tubulins are expressed in human peripheral nerves and the binding of paclitaxel to tubulin may lead to neuropathy. Peripheral neuropathy is a common dose limiting toxicity of paclitaxel. We hypothesized that the occurrence of peripheral neuropathy may correlate with outcome (disease-free survival; DFS).Methods: This analysis sought to describe incidence of peripheral neuropathy following paclitaxel and its association to outcome (DFS) in patients who received paclitaxel (weekly x 12) in the adjuvant HER2+ intergroup trial N9831. Only eligible pts who initiated paclitaxel and did not have peripheral neuropathy at initiation of paclitaxel that were randomized to arms A (955 pts; chemotherapy alone) and C (889 pts; chemotherapy plus concurrent trastuzumab) of N9831 were included. Cox regression analysis stratified by ER/PR status and nodal status was used to compare DFS within arm between patients with and without peripheral neuropathy.Results: Out of 1844 eligible pts, 379 developed neuropathy (20.5%). For pts in arm A, those who developed neuropathy had better DFS than pts who did not (3 yr DFS: 86.2% vs 81.8%; HR 0.65; p=0.01), despite lower doses of paclitaxel in the pts with neuropathy. Grade of neuropathy did not appear to impact DFS. No statistical difference was noted for pts treated in the trastuzumab-containing arm (3 yr DFS: 92.8% vs 91.1% for pts with neuropathy vs not; HR 0.79; p=0.34). There were no differences in paclitaxel dose intensity between arms A and C.Conclusion: Patients with early stage HER2+ breast cancer who received adjuvant paclitaxel-containing chemotherapy in arm A and developed peripheral neuropathy had a better DFS than pts who did not develop neuropathy. This effect was possibly abrogated by the use of trastuzumab in Arm C. This side effect may represent effective bindings of paclitaxel to the target tubulin, lack of point mutations in tubulin at the paclitaxel binding site and/or lack of selective overexpression of β-III tubulin. This is a hypothesis generating study and additional analysis needs to be conducted from other large taxane-based trials.Partial support from Genentech and the Breast Cancer Research Foundation Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2100.