Treatment with trastuzumab for 1 year after adjuvant chemotherapy in patients with HER2-positive early breast cancer: a 4-year follow-up of a randomised controlled trial

Trastuzumab cardiotoxicity: from clinical trials to experimental studies

Epidermal growth factor receptor-2 (HER-2) is overexpressed in 20 to 25% of human breast cancers, which is associated with aggressive tumour growth and poor prognosis. Trastuzumab (Herceptin®) is a humanized monoclonal antibody directed against HER-2, the first highly selective form of therapy targeting HER-2 overexpressing tumours. Although initial trials indicated high efficacy and a favourable safety profile of the drug, the first large, randomized trial prompted a retrospective analysis of cardiac dysfunction in earlier trials utilizing trastuzumab. There has been ongoing debate on the cardiac safety of trastuzumab ever since, initiating numerous clinical and preclinical investigations to better understand the background of trastuzumab cardiotoxicity and evaluate its effects on patient morbidity. Here, we have given a comprehensive overview of our current knowledge on the cardiotoxicity of trastuzumab, primarily focusing on data from clinical trials and highlighting the main molecular mechanisms proposed.

LINKED ARTICLES

This article is part of a themed section on New Insights into Cardiotoxicity Caused by Chemotherapeutic Agents. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.21/issuetoc.

Immunotherapy for breast cancer: past, present, and future

Immunotherapy has shown promise in many solid tumors including melanoma and non-small cell lung cancer with an evolving role in breast cancer. Immunotherapy encompasses a wide range of therapies including immune checkpoint inhibition, monoclonal antibodies, bispecific antibodies, vaccinations, antibody-drug conjugates, and identifying other emerging interventions targeting the tumor microenvironment. Increasing efficacy of these treatments in breast cancer patients requires identification of better biomarkers to guide patient selection; recognizing when to initiate these therapies in multi-modality treatment plans; establishing novel assays to monitor immune-mediated responses; and creating combined systemic therapy options incorporating conventional treatments such as chemotherapy and endocrine therapy. This review will focus on the current role and future directions of many of these immunotherapies in breast cancer, as well as highlighting clinical trials that are investigating several of these active issues.

Neoadjuvant and Adjuvant Therapies for Breast Cancer

Breast cancer remains the most common cancer in women in the United States, the second most common cause of cancer death, and the main cause of death in women ages 45 to 55 years. Molecular analyses have shown that breast cancer is divided into several subtypes (luminal A, luminal B, human epidermal growth factor receptor 2 [HER2] enriched, and basal-like), based on microarray techniques. Patients diagnosed as having breast cancer may undergo adjuvant or neoadjuvant chemotherapy, depending on the tumor size, hormone receptor, HER2/neu status, and desire for breast preservation. Patients with positive estrogen and/or progesterone receptor status benefit from treatment with selective estrogen receptor modulators such as tamoxifen or aromatase inhibitors, based on menopausal status and risk of recurrence. HER2-targeted agents such as trastuzumab and pertuzumab are used in combination with chemotherapy in patients with HER2/neu breast cancer. Triple-negative breast cancer is a unique subtype that lacks specific targets, and its treatment primarily includes chemotherapy. This article reviews the current clinical approaches to the management of patients diagnosed as having breast cancer treated with neoadjuvant and/or adjuvant chemotherapy.

Herceptin® (trastuzumab) in HER2-positive early breast cancer: protocol for a systematic review and cumulative network meta-analysis

BACKGROUND

Human epidermal growth factor receptor 2-positive (HER2+) breast cancer is an aggressive disease that makes up about 20% of all invasive breast cancers. HER2+ breast cancer is associated with poor prognosis and high mortality rates, but the development of HER2-targeted therapies, such as originator trastuzumab (Herceptin®), has substantially improved patient survival. Numerous clinical trials and reviews have investigated the efficacy of HER2-targeted therapies over the past few decades; however, no study has specifically investigated the vast body of evidence on trastuzumab in comparison to chemotherapy regimens, endocrine therapies, and other targeted therapies. This systematic review and cumulative network meta-analysis (NMA) will synthesize available evidence to evaluate the survival benefit conferred by the addition of originator trastuzumab to standard chemotherapy and to compare the most widely used trastuzumab regimens in patients with HER2+ early breast cancer, based on results from randomized controlled trials (RCTs) and comparative observational studies.

METHODS/DESIGN

A systematic search of Embase, MEDLINE®, and the Cochrane Library has been designed by an experienced medical information specialist and peer reviewed by another senior information specialist. RCTs and comparative observational studies of patients with HER2+ early breast cancer indexed from 1990 onwards will be eligible for inclusion. Two investigators will independently assess studies for inclusion and use standardized data extraction templates to collect data on study and patient characteristics. The primary outcome of interest is overall survival. Bayesian cumulative NMA methods will be used to quantify the evolution of publicly available evidence using both fixed and random effects models.

DISCUSSION

This study will evaluate survival trends associated with originator trastuzumab in patients with HER2+ early breast cancer. As originator trastuzumab has been researched in both clinical and real-world settings for close to 20 years, a cumulative NMA is likely to show improved precision around the parameter estimates for trastuzumab now compared with when the drug was initially launched in the USA in 1998. A better understanding of the evolution of publicly available comparative evidence for originator trastuzumab will further inform treatment for patients with HER2+ early breast cancer, providing benefit to patients, health professionals, and researchers.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017055763 https://www.crd.york.ac.uk/PROSPERO.

Therapeutic Implications of the Molecular and Immune Landscape of Triple-Negative Breast Cancer

Treatment and management of breast cancer imposes a heavy burden on public health care, and incidence rates continue to increase. Breast cancer is the most common female neoplasia and primary cause of death among women worldwide. The recognition of breast cancer as a complex and heterogeneous disease, comprising different molecular entities, was a landmark in our understanding of this malignancy. Valuing the impact of the molecular characteristics on tumor behavior enabled a better assessment of a patient's prognosis and increased the predictive power to therapeutic response and clinical outcome. Molecular heterogeneity is also prominent in the triple-negative breast cancer subtype, and is reflected by the distinct prognostic and patient's sensitivity to treatment, being chemotherapy the only systemic treatment currently available. From a therapeutic perspective, gene expression profiling of triple-negative tumors has notably contributed to the exploration of new druggable targets and brought to light the need to align these patients to the various therapies according to their triple-negative subtype. Additionally, the higher amount of tumor infiltrating lymphocytes, and the prevalence of an increased expression of PD-1 receptor and its ligand, PD-L1, in triple-negative tumors, created a new treatment opportunity with immune checkpoint inhibitors. This manuscript addresses the current knowledge on the molecular and immune profiles of breast cancer, and its impact on the development of targeted therapies, with a particular emphasis on the triple-negative subtype.

Impact of repeat HER2 testing after initial equivocal HER2 FISH results using 2013 ASCO/CAP guidelines

PURPOSE

The updated 2013 American Society of Clinical Oncology/College of American Pathologists guideline recommendations for human epidermal growth factor receptor 2 (HER2) testing have made some major changes in HER2 fluorescence in situ hybridization (FISH) interpretation criteria with additional FISH equivocal cases. Repeat HER2 testing is recommended after initial HER2 FISH equivocal results; however, little is known about its impact on final HER2 status. The aim of this study is to investigate whether reflex test clarifies HER2 status, and to characterize clinicopathological features of the newly defined HER2 equivocal group.

METHODS

A total of 886 consecutive cases of primary invasive breast cancer conducted with dual-probe HER2 FISH testing between November 2013 and December 2015 were reviewed. HER2 immunohistochemistry (IHC) and FISH testing were performed on a different tissue block or a new specimen after initial HER2 FISH equivocal results.

RESULTS

Compared to 2007 guideline, 85 (9.6%) cases changed their category by using 2013 guideline. The major change of the 85 cases is that 57 (6.4%) cases in HER2 FISH-negative category changed to equivocal, and the equivocal category cases increased from 36 to 67. HER2 FISH equivocal was significantly associated with HER2 IHC equivocal (2+) and chromosome 17 polysomy (P < 0.01). Repeat testing by IHC and FISH clarified HER2 status in 33 and 42% of HER2 equivocal cases, respectively. Overall 32 (48%) initial HER2 equivocal cases stayed HER2 equivocal after repeat FISH and or IHC testing. These tumors were ER/PR+, with high KI-67 index.

CONCLUSION

New guidelines classify more HER2 FISH equivocal cases. Repeat HER2 testing clarifies HER2 status in about 50% of initial HER2 FISH equivocal cases. In addition, HER2 equivocal cases merit further study as there is limited information about prognosis and optimal treatment strategy for this population.

DUSP4 is associated with increased resistance against anti-HER2 therapy in breast cancer

The majority of patients develop resistance against suppression of HER2-signaling mediated by trastuzumab in HER2 positive breast cancer (BC). HER2 overexpression activates multiple signaling pathways, including the mitogen-activated protein kinase (MAPK) cascade. MAPK phosphatases (MKPs) are essential regulators of MAPKs and participate in many facets of cellular regulation, including proliferation and apoptosis. We aimed to identify whether differential MKPs are associated with resistance to targeted therapy in patients previously treated with trastuzumab. Using gene chip data of 88 HER2-positive, trastuzumab treated BC patients, candidate MKPs were identified by Receiver Operator Characteristics analysis performed in R. Genes were ranked using their achieved area under the curve (AUC) values and were further restricted to markers significantly associated with worse survival. Functional significance of the two strongest predictive markers was evaluated in vitro by gene silencing in HER2 overexpressing, trastuzumab resistant BC cell lines SKTR and JIMT-1. The strongest predictive MKPs were DUSP4/MKP-2 (AUC=0.75, p=0.0096) and DUSP6/MKP-3 (AUC=0.77, p=5.29E-05). Higher expression for these correlated to worse survival (DUSP4: HR=2.05, p=0.009 and DUSP6: HR=2, p=0.0015). Silencing of DUSP4 had significant sensitization effects – viability of DUSP4 siRNA transfected, trastuzumab treated cells decreased significantly compared to scramble-siRNA transfected controls (SKTR: p=0.016; JIMT-1: p=0.016). In contrast, simultaneous treatment with DUSP6 siRNA and trastuzumab did not alter cell proliferation. Our findings suggest that DUSP4 may represent a new potential target to overcome trastuzumab resistance.

Evaluation of the clinical benefits of adjuvant capecitabine monotherapy in elderly women with breast cancer: A retrospective study

Capecitabine is orally administered and may be safely and conveniently used in patients with cancer. The antitumor activity of capecitabine in breast cancer was mostly demonstrated in the salvage therapy setting, whereas the effect of adjuvant capecitabine monotherapy in breast cancer remains unclear. The aim of the present study was to evaluate adjuvant capecitabine monotherapy in elderly women with breast cancer. A total of 251 patients were enrolled and survival was compared between elderly breast cancer patients who received adjuvant capecitabine monotherapy and those who received no chemotherapy. Cancer-specific and disease-free survival curves were compared using log-rank tests and survival curves were calculated using the Kaplan-Meier method. Multivariate analyses were conducted using Cox's proportional hazard regression model. There was no significant difference between the clinicopathological characteristics, including age, tumor size, lymph node status, histological grade and hormone status, between patients in the two groups. The breast cancer-specific survival rate was 89.3% in the capecitabine monotherapy group vs. 81.3% in the no chemotherapy group; the difference was not statistically significant (P=0.128). The disease-free survival rate was 81.7% in the capecitabine monotherapy group vs. 65.3% in the no chemotherapy group. Kaplan-Meier analysis indicated a longer disease-free survival in the capecitabine monotherapy group (P=0.015). On Cox regression analysis, capecitabine monotherapy was found to be associated with the disease-free survival rate (P=0.014, hazard ratio=0.500) but not with the cancer-specific survival rate (P=0.181). The adverse events of capecitabine monotherapy were recorded and there was no chemotherapy interruption due to severe adverse reactions. Therefore, adjuvant capecitabine monotherapy in elderly women with breast cancer is a safe and effective option, as well as a viable alternative for elderly breast cancer patients who refuse standard adjuvant therapy.

Estimating efficacy in trials with selective crossover

When one arm in a trial has a worse early endpoint such as recurrence, a data-monitoring committee might recommend that all participants are offered the apparently superior treatment. The resultant crossover makes it difficult to measure differences between arms thereafter, including for longer-term endpoints such as mortality and disease-specific mortality. In this paper, we consider estimators of the efficacy of treatment on those who would not cross over if randomised to the apparently inferior arm. Binomial and proportional hazards maximum likelihood estimators are developed. The binomial estimator is applied to analysis of a breast cancer treatment trial and compared with intention-to-treat and inverse probability weighting estimators. Full and partial likelihood proportional-hazard model estimators are assessed through computer simulations, where they had similar bias and variance. The new efficacy estimators extend those for all-or-none compliance to this important problem. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Emerging treatments for HER2-positive early-stage breast cancer: focus on neratinib

Over the last decades, a better understanding of breast cancer heterogeneity provided tools for a biologically based personalization of anticancer treatments. In particular, the overexpression of the human epidermal growth factor receptor 2 (HER2) by tumor cells provided a specific target in these HER2-positive tumors. The development of the monoclonal antibody trastuzumab, and its approval in 1998 for the treatment of patients with metastatic disease, radically changed the natural history of this aggressive subtype of breast cancer. These findings provided strong support for the continuous research in targeting the HER2 pathway and implementing the development of new anti-HER2 targeted agents. Besides trastuzumab, a series of other anti-HER2 agents have been developed and are currently being explored for the treatment of breast cancer patients, including those diagnosed with early-stage disease. Among these agents, neratinib, an oral tyrosine kinase inhibitor that irreversibly inhibits HER1, HER2, and HER4 at the intracellular level, has shown promising results, including when administered to patients previously exposed to trastuzumab-based treatment. This article aims to review the available data on the role of the HER2 pathway in breast cancer and on the different targeted agents that have been studied or are currently under development for the treatment of patients with early-stage HER2-positive disease with a particular focus on neratinib.

The role of neratinib in HER2-driven breast cancer

Up to 25% of patients with early-stage HER2+ breast cancer relapse despite adjuvant trastuzumab-based regimens and virtually all patients with metastatic disease eventually die from resistance to existing treatment options. In addition, recent studies indicate that activating HER2 mutations without gene amplification could drive tumor growth in a subset of HER2-negative breast cancer that is not currently eligible for HER2-targeted agents. Neratinib is an irreversible HER kinase inhibitor with activity as extended adjuvant therapy following standard trastuzumab-based adjuvant treatment in a Phase III trial. Phase II trials of neratinib demonstrate promising activity in combination with cytotoxic agents in trastuzumab resistant metastatic HER2+ breast cancer, and either as monotherapy or in combination with fulvestrant for HER2-mutated breast cancers. We anticipate a potential role for neratinib in the therapy of these patient populations.

HER2-positive breast cancer

Anti-HER2 treatment for HER2-positive breast cancer has changed the natural biology of this disease. This Series article reviews the main achievements so far in the treatment of both metastatic and early HER2-positive breast cancer. The success of neoadjuvant therapy in HER2-positive early breast cancer is especially acknowledged, as pertuzumab has been approved on the basis of a higher proportion of patients achieving a pathological complete response with pertuzumab and trastuzumab than with trastuzumab alone in a neoadjuvant study. Event-free survival after the confirmatory adjuvant trial completed recruitment was numerically better with pertuzumab plus trastuzumab than with trastuzumab alone. With survival rates of almost 5 years in women with metastatic HER2-positive breast cancer and 75% of patients achieving a pathological complete response, new treatments in the past decade have clearly improved the prognosis of HER2-positive breast cancer. Despite these achievements, however, the persisting high toll of deaths resulting from HER2-positive breast cancer calls for continued, intensive clinical research of newer therapies and combinations.

Superimposable outcomes for sequential and concomitant administration of adjuvant trastuzumab in HER2-positive breast cancer: Results from the SIGNAL/PHARE prospective cohort

AIM

Adjuvant clinical trials in early human epidermal growth factor receptor 2 (HER2)-positive breast cancer have assessed either sequential or concomitant incorporation of trastuzumab with chemotherapy; only the North Central Cancer Treatment Group (NCCTG)-N9831 trial prospectively compared both modalities. In routine trastuzumab has been incorporated into a concurrent regimen with taxane chemotherapy instead of sequential modality on the basis of a positive risk-benefit ratio. This present study assessed sequential versus concomitant administration of adjuvant trastuzumab.

METHODS

A population combining patients from Protocol for Herceptin^® as Adjuvant therapy with Reduced Exposure (PHARE) a randomised phase III clinical trial (NCT00381901) and SIGNAL (RECF1098) a prospective study specifically designed for Genome-wide Association Studies (GWAS) analyses was studied. In this cohort with 58 months of median follow-up, the comparison in the HER2-positive group of adjuvant trastuzumab and chemotherapy modalities was based on a propensity score methodology. Treatment modalities were based on physician's choice and comparisons adjustment were made by a propensity score methodology. Overall Survival (OS) and Disease-Free Survival (DFS) were estimated using the Kaplan-Meier method, and comparisons between groups were based on the log rank test.

RESULTS

The SIGNAL/PHARE cohort included 11,728 breast cancer cases treated in adjuvant setting; some 5502 of them with HER2-positive tumour: 34.5% (1897/5502) were treated by sequential and 65.5% (3605/5502) by concomitant modality of administration for taxane-chemotherapy and trastuzumab. The adjusted comparison found similar OS (HR = 1.01; 95% CI: 0.86-1.19) and similar DFS (HR = 1.08; 95% CI: 0.96-1.21).

CONCLUSION

These results suggest that the sequential administration of trastuzumab given after the completion of adjuvant chemotherapy might be as valid as the concomitant administration of trastuzumab and taxane chemotherapy in the adjuvant setting.

Abel E, Heinrich G, Schueller K, Schneeweiss A, Fasching P, Beckmann MW, Scholz C, Friedl TWP, Friese K, Pantel K, Fehm T, Janni W, Rack B. The HER2 phenotype of circulating tumor cells in HER2-positive early breast cancer: A translational research project of a prospective randomized phase III trial

BACKGROUND

HER2 is one of the predominant therapeutic targets in breast cancer. The metastatic selection process may lead to discrepancies between the HER2 status of the primary tumor and circulating tumor cells (CTCs). This study analyzed the HER2 status of CTCs in patients with HER2-positive primary breast cancer at the time of diagnosis. Aim of the study was to assess potential discordance of HER2 status between primary tumor and CTCs, as this may have important implications for the use of HER2-targeted therapy.

METHODS

The number and HER2 status of CTCs out of 30ml peripheral blood were assessed in 642 patients using the CellSearch System (Janssen Diagnostics, USA). The cutoff for CTC positivity was the presence of at least 1 CTC, and the cutoff for HER2 positivity of CTCs was the presence of at least 1 CTC with a strong HER2 staining.

RESULTS

258 (40.2%) of the 642 patients were positive for CTCs (median 2; range 1-1,689). 149 (57.8%) of these 258 patients had at least 1 CTC with strong HER2 staining. The presence of HER2-positive CTCs was not associated with tumor size (p = 0.335), histopathological grading (p = 0.976), hormone receptor status (ER: p = 0.626, PR: p = 0.263) or axillary lymph node involvement (p = 0.430). Overall, 83 (32.2%) of the CTC-positive patients exclusively had CTCs with strong HER2 staining, whereas 31 (12.0%) had only CTCs with negative HER2 staining. Within-sample variation in the HER2 status of CTCs was found in 86 (57.8%) of the 149 patients with more than 1 CTC.

CONCLUSION

This study demonstrated that discordance between the HER2 expression of CTCs and that of the primary tumor frequently occurs in early breast cancer. Future follow-up evaluation will assess whether this discrepancy may contribute to trastuzumab resistance.

Switching between intravenous and subcutaneous trastuzumab: Safety results from the PrefHer trial

AIM

To assess the safety and tolerability of switching between subcutaneous (SC) and intravenous (IV) trastuzumab in the PrefHer study (NCT01401166).

PATIENTS AND METHODS

Patients with HER2-positive early breast cancer completed (neo)adjuvant chemotherapy and were randomised to receive four cycles of SC trastuzumab, via single-use injection device (SID; Cohort 1) or hand-held syringe (Cohort 2), followed by four cycles of IV, or vice versa (the crossover period presented here) as part of their 18 standard cycles of adjuvant trastuzumab treatment. Adverse events (AEs) were reported using standard criteria.

RESULTS

Overall, fewer AEs were reported during the IV treatment periods, regardless of administration sequence (IV→SC or SC→IV). Differences in AEs between the SC and IV periods were partly due to variances in grade 1 and 2 local injection site reactions (ISRs) and systemic administration-related reactions (ARRs) and these occurred mainly during SC treatment, as expected. When ISRs and ARRs were excluded, rates of AEs were higher during the first treatment period, compared with the second, in both treatment sequences; otherwise there was no clear pattern in the type of AEs reported. Rates of clinically important events, including grade ≥3 AEs, serious AEs, AEs leading to study drug discontinuation and cardiac AEs, were low and similar between treatment arms (<5%). There were no grade 4 or 5 AEs. No new safety signals for trastuzumab were observed.

CONCLUSIONS

PrefHer revealed that switching from IV to SC trastuzumab (hand-held syringe or SID) or vice versa did not impact the known safety profile of trastuzumab.

Delivering safer immunotherapies for cancer

Cancer immunotherapy is now a powerful clinical reality, with a steady progression of new drug approvals and a massive pipeline of additional treatments in clinical and preclinical development. However, modulation of the immune system can be a double-edged sword: Drugs that activate immune effectors are prone to serious non-specific systemic inflammation and autoimmune side effects. Drug delivery technologies have an important role to play in harnessing the power of immune therapeutics while avoiding on-target/off-tumor toxicities. Here we review mechanisms of toxicity for clinically-relevant immunotherapeutics, and discuss approaches based in drug delivery technology to enhance the safety and potency of these treatments. These include strategies to merge drug delivery with adoptive cellular therapies, targeting immunotherapies to tumors or select immune cells, and localizing therapeutics intratumorally. Rational design employing lessons learned from the drug delivery and nanomedicine fields has the potential to facilitate immunotherapy reaching its full potential.

Association between obesity and trastuzumab-related cardiac toxicity in elderly patients with breast cancer

Purpose

Trastuzumab can improve the prognosis for patients with breast cancer, but its related cardiac toxicity is concerning. This study aimed to identify the risk factors associated with trastuzumab-related cardiac toxicity in elderly patients with HER2-positive breast cancer.

Patients and methods

A total of 133 elderly (≥ 65 years) patients who were diagnosed with breast cancer between June 1, 2007, and January 31, 2016, and received trastuzumab treatment were retrospectively reviewed. Cardiac events were defined as: (1) LVEF reduction of >10% from baseline echocardiography, (2) reduction of LVEF to <50%, and (3) signs and symptoms of heart failure as defined by the Common Terminology Criteria for Adverse Events (CTCAE) accompanied by a decrease in the LVEF. Univariate and multivariate regression analyses were used to determine the contribution of different clinical variables to trastuzumab-related cardiac events.

Results

The median age of the cohort was 71.0 years (range, 65–81 years). The median follow-up period for measurement of left ventricular ejection fraction was 11.0 months (range, 2–71 months). Fifteen patients (11.2%) experienced cardiac events during the follow-up. Multivariate regression analysis revealed that obesity (odd ratio[OR], 4.706; 95% CI, 1.984-10.147; P = 0.002) was a statistically significant risk factor associated with cardiac events.

Conclusion

Obesity is an independent risk factor for trastuzumab-related cardiac toxicity in elderly patients with breast cancer, receiving trastuzumab. Further studies are needed to establish the independent predictive value of obesity on cardiotoxicity in these patients.

Differences in subtype distribution between screen-detected and symptomatic invasive breast cancer and their impact on survival

PURPOSE

Stage shift is considered a major reason for more favorable outcomes in patients with screen-detected breast cancer. However, even after adjusting for clinical stage, unresolved issues concerning the reasons for a survival benefit associated with screening programs remain. This study aims to evaluate differences in subtype distribution and outcomes among patients with screen-detected and symptomatic invasive breast cancer and assess whether variations in subtype distribution could explain differences in prognosis.

METHODS

Survival analysis was performed to estimate the likelihood of distant recurrence and death in 1132 patients. Subtypes were defined as luminal A [estrogen receptor (ER)+ and/or progesterone receptor (PR)+, human epidermal growth factor receptor 2 (HER2)-, and Ki67 low], luminal B (HER2-) (ER+ and/or PR+, HER2-, and Ki67 high), luminal B (HER2+) (ER+ and/or PR+ and HER2+), HER2 overexpressing (ER-, PR-, and HER2+), and triple negative (ER-, PR-, and HER2-).

RESULTS

Screen-detected cancers had favorable clinicopathological characteristics, such as smaller tumor size and a lower frequency of lymph node involvement. Women with screen-detected cancers had a survival advantage. Subtype distribution differed significantly among women with screen-detected and symptomatic cancer. Screen-detected cancers were more likely to be luminal A and less likely to be HER2 overexpressing or triple negative cancer compared with symptomatic cancers (luminal A 61.3 vs. 44.2%, HER2 overexpressing 4.0 vs. 8.0%, triple negative 8.0 vs. 15.9%). Node status, mode of detection, and subtype were independent prognostic factors in the multivariate analysis.

CONCLUSIONS

Differences in subtype distribution between screen-detected and symptomatic cancer could partially explain differences in outcomes.

Efficacy of neratinib in the treatment of HER2/neu-amplified epithelial ovarian carcinoma in vitro and in vivo

Epithelial ovarian carcinoma is the most lethal of gynecologic malignancies. There is a need to optimize the currently available treatment strategies and to urgently develop novel therapeutic agents against chemotherapy-resistant disease. The objective of our study was to evaluate neratinib's preclinical efficacy in treating HER2-amplified ovarian cancer. Neratinib's efficacy in treating HER2-amplified ovarian cancer was studied in vitro utilizing six primary tumor cell lines with differential HER2/neu expression. Flow cytometry was utilized to assess IC₅₀, cell signaling changes, and cell cycle distribution. Neratinib's in vivo efficacy was evaluated in HER2-amplified epithelial ovarian carcinoma xenografts. Three of six (50%) ovarian cancer cell lines were HER2/neu-amplified. Neratinib showed significantly higher efficacy in treating HER2/neu-amplified cell lines when compared to the non-HER2/neu-amplified tumor cell lines (mean ± SEM IC₅₀:0.010 μM ± 0.0003 vs. 0.076 μM ± 0.005 p < 0.0001). Neratinib treatment significantly decreased the phosphorylation of the transcription factor S6, leading to arrest of the cell cycle in G0/G1 phase. Neratinib prolonged survival in mice harboring HER2-amplified epithelial ovarian carcinoma xenografts (p = 0.003). Neratinib inhibits proliferation, signaling, cell cycle progression and tumor growth of HER2-amplified epithelial ovarian carcinoma in vitro. Neratinib inhibits xenograft growth and improves overall survival in HER2/neu-amplified ovarian cancer in vivo. Clinical trials are warranted.

Cost and cost-effectiveness of adjuvant trastuzumab in the real world setting: A study of the Southeast Netherlands Breast Cancer Consortium

Background

We assessed the real world costs and cost-effectiveness of the addition of trastuzumab in HER2 positive early breast cancer compared to chemotherapy alone in the Dutch daily practice as opposed to the results based on trial data and based on a subset of patients that were treated according to the guidelines.

Patients and Methods

In a cohort study, we included all patients with stage I-III invasive breast cancer treated with curative intent in 5 Dutch hospitals between 2005 and 2007 (n=2684).We assessed three scenarios: a real-world scenario, a trial scenario and a guideline scenario, with costs and effectiveness based on either the cohort study, the published trials or the guidelines. Incremental cost-effectiveness ratios (ICERs) and cost-effectiveness acceptability curves (CEACs) were constructed.

Results

Costs were €243,216 and €239,657 for trastuzumab and no trastuzumab for the real world scenario, €224,443 and €218,948 for the guideline scenario and €253,666 and €265,116 for the trial scenario. The QALYs were 0.827, 0.861, 0.993 for the real world, guideline and trial scenario. The corresponding ICERs were €4,304, €6,382 and dominance, respectively. CEACs showed that the probability that trastuzumab is cost-effective is ≥99% in each scenario.

Conclusion

Adjuvant trastuzumab in the real world can be considered cost-effective.

11 years' follow-up of trastuzumab after adjuvant chemotherapy in HER2-positive early breast cancer: final analysis of the HERceptin Adjuvant (HERA) trial

BACKGROUND

Clinical trials have shown that trastuzumab, a recombinant monoclonal antibody against HER2 receptor, significantly improves overall survival and disease-free survival in women with HER2-positive early breast cancer, but long-term follow-up data are needed. We report the results of comparing observation with two durations of trastuzumab treatment at a median follow-up of 11 years, for patients enrolled in the HERA (HERceptin Adjuvant) trial.

METHODS

HERA (BIG 1-01) is an international, multicentre, open-label, phase 3 randomised trial of 5102 women with HER2-positive early breast cancer, who were enrolled from hospitals in 39 countries between Dec 7, 2001, and June 20, 2005. After completion of all primary therapy (including, surgery, chemotherapy, and radiotherapy as indicated), patients were randomly assigned (1:1:1) to receive trastuzumab for 1 year (once at 8 mg/kg of bodyweight intravenously, then 6 mg/kg once every 3 weeks) or for 2 years (with the same dose schedule), or to the observation group. Primary endpoint is disease-free survival, and analyses are in the intention-to-treat population. Hazard ratios (HRs) were estimated from Cox models, and survival curves were estimated by the Kaplan-Meier method. Comparison of 2 years versus 1 year of trastuzumab is based on 366-day landmark analyses. This study is registered with ClinicalTrials.gov (NCT00045032).

FINDINGS

Of the 5102 women randomly assigned in the HERA trial, three patients had no evidence of having provided written informed consent to participate. We followed up the intention-to-treat population of 5099 patients (1697 in observation, 1702 in 1-year trastuzumab, and 1700 in 2-years trastuzumab groups). After a median follow-up of 11 years (IQR 10·09-11·53), random assignment to 1 year of trastuzumab significantly reduced the risk of a disease-free survival event (HR 0·76, 95% CI 0·68-0·86) and death (0·74, 0·64-0·86) compared with observation. 2 years of adjuvant trastuzumab did not improve disease free-survival outcomes compared with 1 year of this drug (HR 1·02, 95% CI 0·89-1·17). Estimates of 10-year disease-free survival were 63% for observation, 69% for 1 year of trastuzumab, and 69% for 2 years of trastuzumab. 884 (52%) patients assigned to the observation group selectively crossed over to receive trastuzumab. Cardiac toxicity remained low in all groups and occurred mostly during the treatment phase. The incidence of secondary cardiac endpoints was 122 (7·3%) in the 2-years trastuzumab group, 74 (4·4%) in the 1-year trastuzumab group, and 15 (0·9%) in the observation group.

INTERPRETATION

1 year of adjuvant trastuzumab after chemotherapy for patients with HER2-positive early breast cancer significantly improves long-term disease-free survival, compared with observation. 2 years of trastuzumab had no additional benefit.

FUNDING

F Hoffmann-La Roche (Roche).

Are there patients with T1 to T2, lymph node-negative breast cancer who are "high-risk" for locoregional disease recurrence?

BACKGROUND

Indications for postmastectomy radiotherapy (PMRT) in patients with T1 to T2, lymph node-negative (N0) breast cancer with "high-risk" features are controversial. The European Organization for Research and Treatment of Cancer (EORTC) 22922 and National Cancer Institute of Canada Clinical Trials Group MA20 trials reporting improved 10-year disease-free survival with lymph node irradiation included patients with high-risk N0 disease, but, to the authors' knowledge, benefits in patients receiving modern systemic therapy are uncertain.

METHODS

The authors retrospectively identified patients with T1 to T2N0 disease who were treated with mastectomy from January 2006 through December 2011. High-risk features included age <40 years, multifocality/multicentricity, lymphovascular invasion, medial/central tumor location, and high nuclear grade.

RESULTS

Among 672 eligible patients, only 15 received PMRT and were excluded. Of the remaining 657 patients, 187 (28%) had 1 high-risk feature and 449 patients (68%) had ≥ 2 high-risk features. A total of 36 patients with unknown tumor grade were excluded from risk analysis. Approximately 98% of patients underwent sentinel lymph node biopsy alone and 86% received adjuvant systemic therapy. At a median of 5.6 years of follow-up, the locoregional disease recurrence (LRR) rate was 4.7% (31 patients). Increasing tumor size was found to be associated with LRR (hazard ratio, 1.70; P = .006), whereas other high-risk features were not (all P > .05). Receipt of systemic therapy decreased the LRR rate (hazard ratio, 0.40; P = .03). Although crude LRR rates increased from 3.8% to 9.4% with 1 versus ≥ 4 high-risk features, the number of risk factors was not found to be significantly associated with LRR (P = .54).

CONCLUSIONS

In the current study, a low crude LRR rate (4.7%) was observed in a large unselected cohort of patients with T1 to T2N0 breast cancer with high-risk features who were treated with mastectomy and systemic therapy without PMRT. Although increasing tumor size and the omission of systemic therapy were found to be predictive, other features did not confer a higher LRR risk either independently or together, and do not by themselves mandate the use of PMRT in this patient population. Cancer 2017;123:2626-33. © 2017 American Cancer Society.

HER2 Pro1170Ala polymorphism is associated with decreased survival rate in HER2-negative breast cancer

The Pro1170Ala polymorphism is one of the most common polymorphisms of human epidermal growth factor receptor 2 (HER2) and may affect the clinical outcome in breast cancer. Therefore, in the present study, the incidence of the HER2 Pro1170Ala polymorphism was determined in 3,305 female patients with operable primary breast cancer using a DNA-sequencing assay, and the potential association with survival was investigated. Of these 3,305 patients, 29% (955/3,305) were homozygous for the Pro/Pro genotype, 51% (1,679/3,305) were heterozygous for the Pro/Ala genotype and 20% (671/3,305) were homozygous for the Ala/Ala genotype. The frequency of this polymorphism conformed to the Hardy-Weinberg equilibrium (P=0.175). No significant association between the HER2 Pro1170Ala polymorphism and recurrence-free survival (RFS) or distant recurrence-free survival (DRFS) was identified in the entire cohort of 3,305 patients. HER2 status was available for 3,170/3,305 patients; no significant association between the HER2 Pro1170Ala polymorphism and survival was identified in HER2-positive patients (n=728). However, among the HER2-negative patients (n=2,442), those with the Pro/Ala or Ala/Ala genotype had a significantly decreased RFS [unadjusted hazard ratio (HR), 1.45; 95% confidence interval (CI), 1.03-2.04; P=0.033] and DRFS (unadjusted HR, 1.65; 95% CI, 1.11-2.44; P=0.012) compared with those with the Pro/Pro genotype. Multivariate analysis revealed that the Pro/Ala or Ala/Ala genotype was an independent unfavorable factor for DRFS (adjusted HR, 1.63; 95% CI, 1.05-2.53; P=0.029) in the subgroup of HER2-negative patients. The results of the present study suggest that patients with HER2-negative breast cancer with the HER2 Pro1170Ala polymorphism variant exhibit a decreased survival outcome.

Trastuzumab infusion reactions in breast cancer. Should we routinely observe after the first dose?

Trastuzumab (Herceptin) is used in neoadjuvant, adjuvant and metastatic breast cancer. Infusion reactions are a common side effect most of which are mild and easily managed, anaphylaxis occurs rarely. The summary of product characteristics recommends observation for 6 hours after the commencement of the first administration; we wanted to evaluate this practice. We assessed first administrations of trastuzumab infusions retrospectively to determine both rate and timing of reactions. Medical and nursing notes of 94 patients who had been prescribed intravenous trastuzumab in 2012 were reviewed; 2 additional patients did not have records available. Fourteen patients received palliative, 73 adjuvant and 7 neoadjuvant trastuzumab.r. Two (2%) had a reaction to trastuzumab occurring at 70 and 80 min from infusion commencement. We did not observe a reaction in the 4.5 hours after the 90 min infusion was complete. We recommend discharge with verbal and written advice immediately after uncomplicated first administration.

Multi-arm Cost-Effectiveness Analysis (CEA) comparing different durations of adjuvant trastuzumab in early breast cancer, from the English NHS payer perspective

BACKGROUND

Trastuzumab improves survival in HER2+ breast cancer patients, with some evidence of adverse cardiac side effects. Current recommendations are to give adjuvant trastuzumab for one year or until recurrence, although trastuzumab treatment for only 9 or 10 weeks has shown similar survival rates to 12-month treatment. We present here a multi-arm joint analysis examining the relative cost-effectiveness of different durations of adjuvant trastuzumab.

METHODS AND FINDINGS

Network meta-analysis (NMA) was used to examine which trials' data to include in the cost-effectiveness analysis (CEA). A network using FinHer (9 weeks vs. zero) and BCIRG006 (12 months vs. zero) trials offered the only jointly randomisable network so these trials were used in the CEA. The 3-arm CEA compared costs and quality-adjusted life-years (QALYs) associated with zero, 9-week and 12-month adjuvant trastuzumab durations in early breast cancer, using a decision tree followed by a Markov model that extrapolated the results to a lifetime time horizon. Pairwise incremental cost-effectiveness ratios (ICERs) were also calculated for each pair of regimens and used in budget impact analysis, and the Bucher method was used to check face validity of the findings. Addition of the PHARE trial (6 months vs. 12 months) to the network, in order to create a 4-arm CEA including the 6-month regimen, was not possible as late randomisation in this trial resulted in recruitment of a different patient population as evidenced by the NMA findings. The CEA results suggest that 9 weeks' trastuzumab is cost-saving and leads to more QALYs than 12 months', i.e. the former dominates the latter. The cost-effectiveness acceptability frontier (CEAF) favours zero trastuzumab at willingness-to-pay levels below £2,500/QALY and treatment for 9 weeks above this threshold. The combination of the NMA and Bucher investigations suggests that the 9-week duration is as efficacious as the 12-month duration for distant-disease-free survival and overall survival, and safer in terms of fewer adverse cardiac events.

CONCLUSIONS

Our CEA results suggest that 9-week trastuzumab dominates 12-month trastuzumab in cost-effectiveness terms at conventional thresholds of willingness to pay for a QALY, and the 9-week regimen is also suggested to be as clinically effective as the 12-month regimen according to the NMA and Bucher analyses. This finding agrees with the results of the E2198 head-to-head study that compared 10 weeks' with 14 months' trastuzumab and found no significant difference. Appropriate trial design and reporting is critical if results are to be synthesisable with existing evidence, as selection bias can lead to recruitment of a different patient population from existing trials. Our analysis was not based on head-to-head trials' data, so the results should be viewed with caution. Short-duration trials would benefit from recruiting larger numbers of participants to reduce uncertainty in the synthesised results.

Well-differentiated invasive breast cancers with equivocal HER2 immunohistochemistry: what is the yield of routine reflex in-situ hybridization testing?

AIMS

The 2013 American Society of Clinical Oncology and the College of American Pathologists (ASCO/CAP) HER2 guidelines recommend testing all invasive breast cancers for HER2, typically with immunohistochemistry (IHC) followed by in-situ hybridization (ISH) when IHC is equivocal. As well-differentiated breast cancers are rarely HER2-positive, we assessed the value of routine reflex HER2 ISH testing for this subset of breast cancers.

METHODS AND RESULTS

We collected HER2 IHC 2+ cases and fluorescence in-situ hybridization (FISH) data from primary breast cancers with well-differentiated tumour types (grade 1 ductal carcinomas, classic lobular carcinomas, tubular, cribriform and pure mucinous carcinomas) at our centre from 2010 to 2015. Haematoxylin and eosin (H&E) and IHC slides were reviewed to confirm tumour type, grade and IHC score based on ASCO/CAP 2013 guidelines and their recent revisions. Of 4633 invasive carcinomas, 1133 had a well-differentiated tumour type; 177 of these were HER2 IHC equivocal, three of which were low-level amplified by FISH (0.3% of all well-differentiated tumours). One amplified case was classic invasive lobular carcinoma and two were invasive ductal carcinomas, grade 1. One amplified case had chromosome 17 monosomy, and one was rescored as HER2 IHC 1+ upon review. 'Basolateral' staining was noted in one amplified case and in 65 of 174 (37.4%) non-amplified cases. This incomplete membranous staining pattern was observed in the majority of invasive ductal carcinomas that were rescored as 1+ according to the revised 2013 guidelines.

CONCLUSIONS

The rate of HER2 amplification among well-differentiated breast cancers is very low. Basolateral staining in well-differentiated tumours may be overinterpreted as HER2 IHC 2+, but is rarely associated with HER2 amplification.

Publishing interim results of randomised clinical trials in peer-reviewed journals

BACKGROUND

Interim analyses of randomised controlled trials are sometimes published before the final results are available. In several cases, the treatment effects were noticeably different after patient recruitment and follow-up completed. We therefore conducted a literature review of peer-reviewed journals to compare the reported treatment effects between interim and final publications and to examine the magnitude of the difference.

METHODS

We performed an electronic search of MEDLINE from 1990 to 2014 (keywords: 'clinical trial' OR 'clinical study' AND 'random*' AND 'interim' OR 'preliminary'), and we manually identified the corresponding final publication. Where the electronic search produced a final report in which the abstract cited interim results, we found the interim publication. We also manually searched every randomised controlled trial in eight journals, covering a range of impact factors and general medical and specialist publications (1996-2014). All paired articles were checked to ensure that the same comparison between interventions was available in both.

RESULTS

In all, 63 studies are included in our review, and the same quantitative comparison was available in 58 of these. The final treatment effects were smaller than the interim ones in 39 (67%) trials and the same size or larger in 19 (33%). There was a marked reduction, defined as a ≥20% decrease in the size of the treatment effect from interim to final analysis, in 11 (19%) trials compared to a marked increase in 3 (5%), p = 0.057. The magnitude of percentage change was larger in trials where commercial support was reported, and increased as the proportion of final events at the interim report decreased in trials where commercial support was reported (interaction p = 0.023). There was no evidence of a difference between trials that stopped recruitment at the interim analysis where this was reported as being pre-specified versus those that were not pre-specified (interaction p = 0.87).

CONCLUSION

Published interim trial results were more likely to be associated with larger treatment effects than those based on the final report. Publishing interim results should be discouraged, in order to have reliable estimates of treatment effects for clinical decision-making, regulatory authority reviews and health economic analyses. Our work should be expanded to include conference publications and manual searches of additional journal publications.

HER-2 Positive Breast Cancer - a Mini-Review

Breast cancer is one of among all cancers with increased incidence, high mortality rate, and high economic and social costs. The the most common type of cancer among females worldwide, breast cancer is actually the uncontrolled proliferation of cells which attain malignancy. Recently it has shown that breast cancer contributes 11% among all types of cancer diagnosed globally on an annual basis and it is one of the leading causes of death among women. The human epidermal growth factor receptor 2 (HER-2) is a receptor tyrosine-protein kinase erbB-2 normally involved in the proliferation and division of breast cells. In some abnormal cases the HER2 gene does not work correctly and makes too many copies of itself. HER2-positive (HER2+) breast cancers constitute an aggressive type of breast cancer and tend to grow faster and are more likely to spread. However, therapies that specifically target HER2, such as Herceptin® (traztuzumab), are very effective. HER2 targeted therapies, has significantly improved the therapeutic outcome for patients with HER2 positive breast cancer.

A phase-I study of lapatinib in combination with foretinib, a c-MET, AXL and vascular endothelial growth factor receptor inhibitor, in human epidermal growth factor receptor 2 (HER-2)-positive metastatic breast cancer

BACKGROUND

The mechanisms of resistance to anti-human epidermal growth factor receptor 2 (HER 2) therapies are unclear but may include the tyrosine-protein kinase Met (c-Met), vascular endothelial growth factor (VEGF) and AXL pathways. Foretinib is an inhibitor of c-Met, VEGF receptor 2 (VEGFR-2), platelet-derived growth factor receptor beta (PDGFRB), AXL, Fms-like tyrosine kinase 3 (FLT3), angiopoiten receptor (TIE-2), RET and RON kinases. This phase Ib study sought to establish the associated toxicities, pharmacokinetics (PK) and recommended phase II doses (RP2D) of foretinib and lapatinib in a cohort of HER-2-positive patients with metastatic breast cancer (MBC).

METHODS

Women with HER-2 positive MBC, Performance status (PS 0-2), and no limit on number of prior chemotherapies or lines of anti-HER-2 therapies were enrolled. A 3 + 3 dose escalation design was utilized. Four dose levels were intended with starting doses of foretinib 30 mg and lapatinib 750 mg orally once a day (OD) on a 4-weekly cycle. Assessment of c-MET status from the primary archival tissue was performed.

RESULTS

We enrolled 19 patients, all evaluable for toxicity assessment and for response evaluation. Median age was 60 years (34-86 years), 95% were PS 0-1, 53% were estrogen receptor-positive and 95% had at least one prior anti-HER-2-based regimen. The fourth dose level was reached (foretinib 45 mg/lapatinib 1250 mg) with dose-limiting toxicities of grade-3 diarrhea and fatigue. There was only one grade-4 non-hematological toxicity across all dose levels. There were no PK interactions between the agents. A median of two cycles was delivered across the dose levels (range 1-20) with associated progression-free survival of 3.2 months (95% CI 1.61-4.34 months). By immunohistochemical assessment with a specified cutoff, none of the 17 samples tested were classified as positive for c-Met.

CONCLUSIONS

The RP2D of the combined foretinib and lapatinib is 45 mg and 1000 mg PO OD, respectively. Limited activity was seen with this combination in a predominantly unselected cohort of HER-2-positive patients with MBC.

Early dissemination seeds metastasis in breast cancer

Accumulating data suggest that metastatic dissemination often occurs early during tumour formation but the mechanisms of early metastatic spread have not yet been addressed. Here, we studied metastasis in a HER2-driven mouse breast cancer model and found that progesterone-induced signalling triggered migration of cancer cells from early lesions shortly after HER2 activation, but promoted proliferation in advanced primary tumour cells. The switch from migration to proliferation was regulated by elevated HER2 expression and increased tumour cell density involving miRNA-mediated progesterone receptor (PGR) down-regulation and was reversible. Cells from early, low-density lesions displayed more stemness features than cells from dense, advanced tumours, migrated more and founded more metastases. Strikingly, we found that at least 80% of metastases were derived from early disseminated cancer cells (DCC). Karyotypic and phenotypic analysis of human disseminated cancer cells and primary tumours corroborated the relevance of these findings for human metastatic dissemination.

Global and regional patterns of longitudinal strain in screening for chemotherapy-induced cardiotoxicity

INTRODUCTION

Serial echocardiographic assessment of left ventricular ejection fraction (LVEF) is the gold standard in screening for chemotherapy-induced cardiotoxicity (CIC). Measurement of myocardial deformation using speckle tracking enables more detailed assessment of myocardial contractility. The aim of this study was to determine the relationship between global and regional longitudinal strain and CIC.

METHODS

This was a prospective study of 158 breast cancer patients undergoing chemotherapy with anthracyclines with or without adjuvant trastuzumab who underwent serial monitoring by transthoracic echocardiography with assessment of myocardial deformation. CIC was defined as a decrease in LVEF to <53%. Global longitudinal strain (GLS) was estimated using EchoPAC BT12 software on a GE Vivid E9 cardiac ultrasound system. Patients were classified according to the 2015 ASE/EACVI criteria as having impaired myocardial deformation when GLS was reduced (less negative), with a cutoff of -18%.

RESULTS

During a mean follow-up of 5.4 months (1-48 months), the incidence of CIC was 18.9%. A decrease in GLS was observed during follow-up for the entire cohort (baseline GLS -20.1±3.5% vs. -18.7±3.4% at last follow-up assessment, p=0.001). A total of 97 patients (61.4%) were observed to have impaired myocardial deformation (GLS ≥18%) at some point during follow-up. This decrease was more significant in patients who eventually developed CIC (GLS -17.2±2.5%, p=0.02). On analysis of regional strain, impaired contractility was observed in the septal (6 out of 6) and anterior (2 out of 3) segments. Multivariate logistic regression showed that patients who developed impaired longitudinal strain had a 4.9-fold increased risk of developing CIC (odds ratio 4.88, confidence interval 1.32-18.0, p=0.017).

CONCLUSIONS

Worsening of myocardial deformation as assessed by speckle tracking is common in breast cancer patients undergoing chemotherapy, with predominantly septal and anterior wall involvement. Impaired myocardial deformation was independently associated with increased incidence of CIC.

Adjuvant trastuzumab: a 10-year overview of its benefit

INTRODUCTION

Anti-HER2 targeted therapy is one of the key advances in the treatment of breast cancer that have occurred in the last 20 years. In the adjuvant setting, the use of trastuzumab has led to prolonged and sustained survival benefit with very little toxicity as also confirmed by the 10-year follow-up results from the pivotal trials. Despite the survival improvement, several key issues are not entirely resolved in this field. These issues have led to multiple research efforts in de-escalating or escalating the standard treatment with chemotherapy and 1 year of adjuvant trastuzumab. Areas covered: In this paper, we present an in depth overview on the state of the art on these key issues of refining decision-making in adjuvant anti-HER2 therapy. Expert commentary: Despite many important research efforts in the field, chemotherapy plus trastuzumab for a total duration of 1 year remains the standard of care. However, recent data showed that besides standard anthracycline- and taxane-based cytotoxic therapy, alternative chemotherapy regimens can now be proposed to patients with small tumors without nodal involvement and to women at high-risk of developing cardiotoxicity. Of note, besides HER2 itself, biomarkers predicting patients who may truly benefit from anti-HER2 agents are still lacking.

Clinical outcomes according to molecular subtypes in stage II-III breast cancer patients treated with neoadjuvant chemotherapy followed by surgery and radiotherapy

AIM

We evaluated the tumor response and clinical outcomes according to molecular subtypes in stage II-III breast cancer patients who received neo-adjuvant chemotherapy (NAC) followed by surgery and radiotherapy.

METHODS

We retrospectively analyzed 329 patients with clinical stage II-III breast cancer who received NAC followed by surgery and radiotherapy. Luminal A and B, HER2-enriched and triple-negative subgroups were identified.

RESULTS

The overall pathologic complete response (pCR) rate after NAC was 20.1% and the HER2-enriched subgroup had the highest pCR rate (43.6%), whereas luminal A showed the lowest rate of pCR (4.6%). The median follow-up duration was 55 months (range, 5-98 months). The 5-year overall survival (OS) and disease-free survival (DFS) rates were 88.9% and 72.9%, respectively. In subgroup analysis, according to the pathologic response (pCR vs non-pCR), the triple-negative subtype exhibited a significant difference in 5-year OS rate (100.0% vs 71.6%, P = 0.005) and 5-year DFS rate (93.1% vs 55.1%, P < 0.001). A distinct survival difference according to molecular subtype was found, particularly in the non-pCR group (5-year OS and DFS, P < 0.001, respectively).

CONCLUSIONS

The non-pCR group showed significantly decreased 5-year OS and DFS rates compared to the pCR group, especially in triple negative and HER2-enriched breast cancer patients. A significant difference in survival rates and molecular subtypes was found in patients who failed to attain pCR.

Clinical Overestimation of HER2 Positivity in Early Estrogen and Progesterone Receptor-Positive Breast Cancer and the Value of Molecular Subtyping Using BluePrint

PURPOSE

Human epidermal growth factor receptor 2 (HER2) positivity is an important prognostic and predictive indicator in breast cancer. HER2 status is determined by immunohistochemistry and fluorescent in situ hybridization (FISH), which are potentially inaccurate techniques as a result of several technical factors, polysomy of chromosome 17, and amplification or overexpression of CEP17 (centromeric probe for chromosome 17) and/or HER2. In South Africa, HER2-positive tumors are excluded from a MammaPrint (MP; Agendia BV, Amsterdam, Netherlands) pretest algorithm. Clinical HER2 status has been reported to correlate poorly with molecular subtype. The aim of this study was to investigate the correlation of clinical HER2 status with BluePrint (BP) molecular subtyping.

METHODS

Clinico-pathologic and genomic information was extracted from a prospectively collected central MP database containing records of 256 estrogen receptor-positive and/or progesterone receptor-positive tumors. Twenty-one tumors considered HER2 positive on immunohistochemistry or FISH were identified for this study.

RESULTS

The median age of patients was 56 years (range, 34 to 77 years), with a median tumor size of 16 mm (3 to 27 mm). Four (19%) tumors were confirmed HER2-enriched subtype, six (29%) were luminal A, and 11 (52%) were luminal B. The positive predictive values of HER2/CEP17 ratio ≥ 2 and HER2 copy number ≥ 6 were only 29% and 40%, respectively. The differences in means for HER2/CEP17 ratio were significant between BP HER2-enriched versus luminal (P = .0249; 95% CI, 0.12 to 1.21) and MP high-risk versus low-risk tumors (P = .0002; 95% CI, 0.40 to 1.06).

CONCLUSION

Of the 21 tumors considered clinically HER2 positive, only four were HER2-enriched subtype with BP, indicating an overestimation of HER2 positivity. FISH testing has a poor positive predictive value.

Treatment planning and evaluation of gated radiotherapy in left-sided breast cancer patients using the CatalystTM/SentinelTM system for deep inspiration breath-hold (DIBH)

BACKGROUND

There is a potential for adverse cardiovascular effects in long-term breast cancer survivors following adjuvant radiotherapy (RT). For this purpose, the deep inspiration breath-hold technique (DIBH) has been introduced into clinical practice, to maximally reduce the radiation dose to the heart. However, there are a variety of DIBH delivery techniques, patient positioning and visual patient feedback mechanisms. The aim of the present study was to evaluate the application of radiotherapy in DIBH using the Catalyst^TM/Sentinel^TM system, with a special emphasis on treatment planning and dosimetric plan comparison in free breathing (FB) and DIBH.

PATIENTS AND METHODS

A total of 13 patients with left-sided breast cancer following breast conserving surgery were included in this prospective clinical trial. For treatment application the Catalyst^TM/Sentinel^TM system (C-RAD AB, Uppsala, Sweden) was used and gating control was performed by an audio-visual patient feedback system. CT and surface data were acquired in FB and DIBH and dual treatment plans were created using Pencil Beam and Collapsed Cone Convolution. Dosimetric output parameters of organs at risk were compared using Wilcoxon signed-rank test. Central lung distance (CLD) was retrieved from iView^TM portal images during treatment delivery.

RESULTS

The system contains a laser surface scanner (Sentinel^TM) and an optical surface scanner (Catalyst^TM) interconnected to the LINAC systems via a gating interface and allows for a continuous and touchless surface scanning. Overall, 225 treatment fractions with audio-visual guidance were completed without any substantial difficulties. Following initial patient training and treatment setup, radiotherapy in DIBH with the Catalyst^TM/Sentinel^TM system was time-efficient and reliable. Following dual treatment planning for all patients, nine of 13 patients were treated in DIBH. In these patients, the reduction of the mean heart dose for DIBH compared to FB was 52 % (2.73 to 1.31 Gy; p = 0.011). The maximum doses to the heart and LAD were reduced by 59 % (47.90 to 19.74 Gy; p = 0.008) and 75 % (38.55 to 9.66 Gy; p = 0.008), respectively. In six of the nine patients the heart completely moved out of the treatment field by DIBH. The standard deviation of the CLD varied between 0.12 and 0.29 cm (mean: 0.16 cm).

CONCLUSION

The Catalyst^TM/Sentinel^TM system enabled a fast and reliable application and surveillance of DIBH in daily clinical routine. Furthermore, the present data show that using the DIBH technique during RT could significantly reduce high dose areas and mean doses to the heart.

TRIAL REGISTRATION

DRKS: DRKS00010929 registered on 5. August 2016.

Neoadjuvant Chemotherapy with Docetaxel, Carboplatin and Weekly Trastuzumab Is Active in HER2-Positive Early Breast Cancer: Results after a Median Follow-Up of over 4 Years

INTRODUCTION

Most patients with HER2-positive breast cancer receive chemotherapy and trastuzumab. Data from adjuvant trials have shown that the combination of docetaxel, carboplatin and weekly trastuzumab (TCH) is well tolerated and as effective as anthracycline-containing regimes. Previous investigations on neoadjuvant treatment with taxanes, platinum salts and trastuzumab showed pathological complete remission (pCR) rates between 43.3 and 76%. To date, the longest published follow-up in this indication is 3 years. Here we present 4-year follow-up data for a cohort of 78 patients treated with neoadjuvant TCH.

METHODS

Between 2009 and 2014 we treated 78 patients with operable HER2-positive breast cancer with a neoadjuvant schedule of docetaxel (75 mg/m²) and carboplatin (AUC 6) every 3 weeks (q3w) and trastuzumab (4 mg/kg loading dose then 2 mg/kg) q1w. Lymph node involvement was verified by sentinel lymph node or core-cut biopsy. Patients were diagnosed at a mean age of 55.5 years; 65.4% had hormone receptor-positive tumors, 34.6% presented with grade 3 disease and 51.3% of patients were node positive. Patients were monitored every 2 cycles by ultrasound. After 6 cycles of chemotherapy all patients had surgery. Axillary dissection was performed in case of positive lymph node status prior to TCH. After surgery, trastuzumab was continued q3w up to 1 year.

RESULTS

No grade III/IV toxicities occurred and no case of congestive heart failure was observed. Neither dose modifications nor dose delays were necessary. 34 of the 78 patients (43.6%) achieved a pCR, 27 of the 40 node-positive patients (67.5%) experienced nodal conversion. After a median follow up of 48.5 months the disease-free survival (DFS) was 84.6%, the distant disease-free survival (DDFS) was 87.2% and the overall survival (OS) was 91%. Only T stage and nodal status at baseline were found to be significantly associated with survival estimates.

CONCLUSION

The anthracycline-free regimen TCH is effective and safe in the neoadjuvant therapy of HER2-positive breast cancer, yielding DFS, DDFS and OS probabilities comparable to the results of adjuvant trials. Our data support the use of TCH as a neoadjuvant therapy regimen for patients with HER2-positive breast cancer. They also strongly encourage the use of taxanes and platinum salts as the chemotherapy backbone in studies investigating dual blockade with trastuzumab and pertuzumab in the neoadjuvant setting.

Evaluation of human epidermal growth factor receptor 2 (HER2) single nucleotide polymorphisms (SNPs) in normal and breast tumor tissues and their link with breast cancer prognostic factors

Amplification of the human epidermal growth factor receptor 2 (HER2) gene is associated with worse prognosis and decreased overall survival in breast cancer patients. The HER2 gene contains several polymorphisms; two of the best-characterized HER2 polymorphisms are Ile655Val and Ala1170Pro. The aim of this study was to evaluate the association between these two HER2 polymorphisms in normal breast and breast cancer tissues and known breast cancer prognostic factors in a retrospective cohort study of 73 women with non-metastatic HER2-positive breast cancer. HER2 polymorphisms were assessed in breast cancer tissue and normal breast tissue using TaqMan assay. Ala1170Pro polymorphism in normal breast tissue was associated with age at diagnosis (p = 0.007), tumor size (p = 0.004) and lymphovascular invasion (p = 0.06). Similar significant associations in cancer tissues were observed. No association between the Ile655Val polymorphism and prognostic factors were observed. However, we found significant differences in the distribution of Ile655Val (p = 0.03) and Ala1170Pro (p = 0.01) genotypes between normal breast and breast tumor tissues. This study demonstrates that only the Ala1170Pro polymorphism is associated with prognostic factors in HER2-positive breast cancer patients. Moreover, our results suggest that both HER2 polymorphisms could play a significant role in carcinogenesis in non-metastatic HER2-positive breast cancer women.

Treatment of brain metastases in the modern genomic era

Development of brain metastasis (BM) portends a dismal prognosis for patients with cancer. Melanomas and carcinomas of the lung, breast, and kidney are the most common malignancies to metastasize to the brain. Recent advances in molecular genetics have enabled the identification of actionable, clinically relevant genetic alterations within primary tumors and their corresponding metastases. Adoption of genotype-guided treatment strategies for the management of systemic malignancy has resulted in dramatic and durable responses. Unfortunately, despite these therapeutic advances, central nervous system (CNS) relapses are not uncommon. Although these relapses have historically been attributed to limited blood brain barrier penetration of anti-neoplastic agents, recent work has demonstrated genetic heterogeneity such that metastatic sites, including BM, harbor relevant genetic alterations that are not present in primary tumor biopsies. This improved insight into molecular mechanisms underlying site specific recurrences can inform strategies for targeting these oncogenic drivers. Thus, development of rational, genomically guided CNS-penetrant therapies is crucial for ongoing therapeutic success.

Synergistic antitumor efficacy against the EGFRvIII+HER2+ breast cancers by combining trastuzumab with anti-EGFRvIII antibody CH12

Although Trastuzumab, an anti-HER2 antibody, benefits certain patients with HER2-overexpressing breast cancer, de novo or acquired trastuzumab resistance remains a haunting issue. EGFRvIII, co-expressing with HER2 in some breast tumors, indicates a poor clinical prognosis. However, the role of EGFRvIII in the function of trastuzumab is not clear. Here, we demonstrated that EGFRvIII overexpression contributed to de novo trastuzumab resistance and the feedback activation of STAT3 caused by trastuzumab also resulted in acquired resistance in EGFRvIII(+)HER2(+) breast cancers. CH12, a highly effective anti-EGFRvIII monoclonal antibody that preferentially binds to EGFRvIII, significantly suppressed the growth of EGFRvIII+HER2(+) breast cancer cells in vitro and in vivo. Importantly, CH12 in combination with trastuzumab had a synergistic inhibitory effect on EGFRvIII(+)HER2(+) breast cancers in vitro and in vivo via attenuating the phosphorylation of EGFR and HER2 and their downstream signal pathways more effectively and reversing STAT3 feedback activation. Moreover, the combination therapy suppressed angiogenesis and induced cell apoptosis significantly. Together, these results suggested a synergistic efficacy of the combination of trastuzumab with CH12 against EGFRvIII(+)HER2(+) breast cancers, which might be a potential clinical application in the future.

A miRNA-based signature predicts development of disease recurrence in HER2 positive breast cancer after adjuvant trastuzumab-based treatment

Approximately 20% of HER2 positive breast cancer develops disease recurrence after adjuvant trastuzumab treatment. This study aimed to develop a molecular prognostic model that can reliably stratify patients by risk of developing disease recurrence. Using miRNA microarrays, nine miRNAs that differentially expressed between the recurrent and non-recurrent patients were identified. Then, we validated the expression of these miRNAs using qRT-PCR in training set (n = 101), and generated a 2-miRNA (miR-4734 and miR-150-5p) based prognostic signature. The prognostic accuracy of this classifier was further confirmed in an internal testing set (n = 57), and an external independent testing set (n = 53). Besides, by comparing the ROC curves, we found the incorporation of this miRNA based classifier into TNM stage could improve the prognostic performance of TNM system. The results indicated the 2-miRNA based signature was a reliable prognostic biomarker for patients with HER2 positive breast cancer.

Comparison of the types of candidate reference samples for quality control of human epidermal growth factor receptor 2 status detection

Background

Human epidermal growth factor receptor 2 (HER2) is as a target gene for trastuzumab in patients with breast cancer. Accurate determination of HER2 status and strict quality control are necessary to ensure reproducibility and accuracy of the techniques used for the determination of HER2 status.

Methods

We used three different types of samples: formalin-fixed and paraffin-embedded (FFPE) samples prepared from cell lines, agarose gel samples using cell lines, and xenograft tumor samples. One cell line for FFPE or xenografts did not overexpress HER2, while the others showed different levels of HER2 overexpression. We compared the morphology, HER2 gene amplification status, and HER2 protein expression status of these samples with those of clinical specimens.

Results

We successfully produced three kinds of samples for quality control. Cells from the cell line-sample sections were dispersed while those from the agarose gel-sample sections and xenograft tumor sample sections (prepared from the both cell lines) were concentrated in one area. The FISH results for all three kinds of samples were as expected. The IHC results of the cell line samples and xenograft tumor samples were as expected, but the staining level of the agarose gel samples, using HER2-overexpressed cell lines was weak which might be regarded as a false negative result.

Conclusions

Xenograft tumor samples might be used as an additional option for quality control in FISH and IHC. However, it might not replace the clinical specimen quality controls directly.

Electronic supplementary material

The online version of this article (doi:10.1186/s13000-016-0537-8) contains supplementary material, which is available to authorized users.