Reversibility of trastuzumab-related cardiotoxicity: new insights based on clinical course and response to medical treatment

Lisinopril or Coreg CR in reducing cardiotoxicity in women with breast cancer receiving trastuzumab: A rationale and design of a randomized clinical trial

BACKGROUND

Trastuzumab (TZB) is an established therapy for HER2-positive breast cancer. The use of TZB is commonly associated with cardiotoxicity manifesting as asymptomatic decrease in left ventricular ejection fraction (LVEF) or overt heart failure. Several studies demonstrated favorable effects of angiotensin-converting enzyme (ACE) inhibitors and β-blockers (BBs) in the prevention of chemotherapy-induced cardiotoxicity. We hypothesize that patients, randomized to receive an ACE inhibitor or a BB during trastuzumab therapy for breast cancer, will maintain a higher LVEF than patients randomized to placebo.

METHODS AND RESULTS

We designed a prospective, multicenter, randomized, phase II placebo-controlled clinical trial to evaluate the effects of an ACE inhibitor (lisinopril) and a BB (carvedilol phosphate-extended release) on cardiotoxicity in patients with breast cancer who are receiving adjuvant or neoadjuvant TZB therapy. The primary objectives include (1) comparison of incidence of cardiotoxicity and (2) comparison of LVEF as a continuous variable in between the arms. Cardiotoxicity was defined as an absolute decrease in LVEF from baseline of ≥10% at follow-up or an absolute decrease of ≥5% in LVEF from baseline for individuals with <50% LVEF at follow-up. The target accrual is 468 participants, representing patients both with and without anthracycline exposure. The enrollment is completed. The trial is co-sponsored by University of South Florida and National Cancer Institute. The LVEF is being evaluated by echocardiography or multigated acquisition scan.

CONCLUSIONS

If we can demonstrate that the use of an ACE inhibitor or a BB can reduce the degree of TZB-induced cardiotoxicity, it is hoped that patients will receive complete and uninterrupted TZB therapy for breast cancer without compromising cardiac function.

Comprehensive review on cardio-oncology: Role of multimodality imaging

Cancer and cardiovascular disease are the two leading causes of mortality worldwide. Evolving oncologic therapy, including the use of newer targeted agents, has led to an improvement in survival from childhood- and adult-onset cancers. Consequently, there has been a growing realization of cardiotoxic complications related to cancer therapy, with some complications manifesting over months to decades after completion of cancer treatment. This paper reviews cancer therapeutics-related cardiovascular toxicity and its manifestations, multimodality imaging techniques for surveillance and detection of this complication, and the current state of knowledge in this emerging field.

Cardio-Oncology: Cancer Therapy-related Cardiovascular Complications in a Molecular Targeted Era: New Concepts and Perspectives

Cardio-oncology is a medical discipline that identifies, prevents, and treats the cardiovascular complications related to cancer therapy. Due to the remarkable proliferation of new cancer therapies causing cardiovascular complications, such as hypertension, heart failure, vascular complications, and cardiac arrhythmia, we provide an extensive, comprehensive revision of the most up-to-date scientific information available on the cardiovascular complications associated with the use of newer, novel chemotherapeutic agents, including their reported incidence, suggested pathophysiology, clinical manifestations, potential treatment, and prevention. The authors consider this topic to be relevant for the clinicians since cardiovascular complications associated with the administration of recently approved drugs are relatively underappreciated. The purpose of this article is to provide a state-of-the-art review of cardiovascular complications associated with the use of newer, novel chemotherapeutic agents and targeted therapies, including their reported incidence, suggested pathophysiology, clinical manifestations, potential treatment, and prevention.  Ongoing efforts are needed to provide a better understanding of the frequency, mechanisms of disease, prevention, and treatment of cardiovascular complications induced by the newer, novel chemotherapeutic agents. Development of a cardio-oncology discipline is warranted in order to promote task forces aimed at the creation of oncology patient-centered guidelines for the detection, prevention, and treatment of potential cardiovascular side effects associated with newer cancer therapies.

Detailed Echocardiographic Phenotyping in Breast Cancer Patients: Associations With Ejection Fraction Decline, Recovery, and Heart Failure Symptoms Over 3 Years of Follow-Up

BACKGROUND

Cardiovascular disease in patients with breast cancer is of growing concern. The longitudinal effects of commonly used therapies, including doxorubicin and trastuzumab, on cardiac remodeling and function remain unknown in this population. We aimed to define the changes in echocardiographic parameters of structure, function, and ventricular-arterial coupling, and their associations with left ventricular ejection fraction (LVEF) and heart failure symptoms.

METHODS

In a longitudinal prospective cohort study of 277 breast cancer participants receiving doxorubicin (Dox), trastuzumab (Tras), or both (Dox+Tras), we obtained 1249 echocardiograms over a median follow-up of 2.0 (interquartile range, 1.0-3.0) years. Left ventricular structure, diastolic and contractile function, and ventricular-arterial coupling measures were quantified in a core laboratory blinded to participant characteristics. We evaluated changes in echocardiographic parameters over time, and used repeated-measures regression models to define their association with LVEF decline and recovery. Linear regression models defined the association between early changes in these parameters and subsequent changes in LVEF and heart failure symptoms.

RESULTS

Overall, 177 (64%) received Dox, 51 (18%) received Tras, and 49 (18%) received Dox+Tras. With Dox, there was a sustained, modest decrease in LVEF over the follow-up duration (1-year change in LVEF -3.6%; 95% confidence interval [CI], -4.4% to -2.8%; 3-year change -3.8%; 95% CI, -5.1% to -2.5%). With Tras, a similar LVEF decline was observed at 1 year (-4.5%; 95% CI, -6.0% to -2.9%) and 3 years (-2.8%; 95%CI, -5.3 to -0.4%). Participants receiving Dox+Tras demonstrated the greatest declines at 1 year (-6.6%; 95% CI, -8.2 to -5.0%), with partial recovery at 3 years (-2.8%; 95% CI, -4.8 to -0.8%). LVEF declines and recovery were associated primarily with changes in systolic volumes, longitudinal and circumferential strain, and ventricular-arterial coupling indices, effective arterial elastance (Ea) and the coupling ratio Ea/Eessb, without evidence for effect modification across therapies. Early changes in volumes, strain, and Ea/Eessb at 4 to 6 months were associated with 1- and 2-year LVEF changes. Similarly, early changes in strain and Ea were associated with worsening heart failure symptoms at 1 year.

CONCLUSIONS

Doxorubicin and trastuzumab resulted in modest, persistent declines in LVEF at 3 years. Changes in volumes, strain, and ventricular-arterial coupling were consistently associated with concurrent and subsequent LVEF declines and recovery across therapies.

Tyrosine kinase-targeting drugs-associated heart failure

Background:

The impact of cancer therapies on cardiac disease in the general adult cancer survivor population is largely unknown. Our objective was to evaluate which tyrosine kinase-targeting drugs are associated with greater risk for new-onset heart failure (HF).

Methods:

A nested case–control analysis was conducted within a cohort of 27 992 patients of Clalit Health Services, newly treated with a tyrosine kinase-targeting, and/or chemotherapeutic drug, for a malignant disease, between 1 January 2005 and 31 December 2012. Each new case of HF was matched to up to 30 controls from the cohort on calendar year of cohort entry, age, gender, and duration of follow-up. Main outcome measure was odds ratio (OR) with 95% confidence interval (CI) of new-onset HF.

Results:

There were 936 incident cases of HF during 71 742 person-years of follow-up. Trastuzumab (OR 1.90, 95% CI 1.46–2.49), cetuximab (OR 1.72, 1.10–2.69), panitumumab (OR 3.01, 1.02–8.85), and sunitinib (OR 3.39, 1.78–6.47) were associated with increased HF risk. Comorbidity independently associated with higher risk in a multivariable conditional regression model was diabetes mellitus, hypertension, chronic renal failure, ischaemic heart disease, valvular heart disease, arrhythmia, and smoking.

Conclusions:

Trastuzumab, cetuximab, panitumumab, and sunitinib are associated with increased risk for new-onset HF.

Galician consensus on management of cardiotoxicity in breast cancer: risk factors, prevention, and early intervention

This Galician consensus statement is a joint oncologists/cardiologists initiative indented to establish basic recommendations on how to prevent and to manage the cardiotoxicity in breast cancer with the aim of ensuring an optimal cardiovascular care of these patients. A clinical screening of the patients before treatment is recommended to stratify them into a determined risk group based on their intrinsic cardiovascular risk factors and those extrinsic arose from breast cancer therapy, thereby providing individualized preventive and monitoring measures. Suitable initial and ongoing assessments for patients with low and moderate/high risk and planned treatment with anthracyclines and trastuzumab are given; also, measures aimed at preventing and correcting any modifiable risk factor are pointed out .

Preventing antiblastic drug-related cardiomyopathy: old and new therapeutic strategies

Because of the recent advances in chemotherapeutic protocols, cancer survival has improved significantly, although cardiovascular disease has become a major cause of morbidity and mortality among cancer survivors: in addition to the well-known cardiotoxicity (CTX) from anthracyclines, biologic drugs that target molecules that are active in cancer biology also interfere with cardiovascular homeostasis.Pharmacological and non-pharmacological strategies to protect the cardiovascular structure and function are the best approaches to reducing the prevalence of cardiomyopathy linked to anticancer drugs. Extensive efforts have been devoted to identifying and testing strategies to achieve this end, but little consensus has been reached on a common and shared operability.Timing, dose and mode of chemotherapy administration play a crucial role in the development of acute or late myocardial dysfunction. Primary prevention initiatives cover a wide area that ranges from conventional heart failure drugs, such as β-blockers and renin-angiotensin-aldosterone system antagonists to nutritional supplementation and physical training. Additional studies on the pathophysiology and cellular mechanisms of anticancer-drug-related CTX will enable the introduction of novel therapies.We present various typologies of prevention strategies, describing the approaches that have already been used and those that could be effective on the basis of a better understanding of pharmacokinetic and pharmacodynamic CTX mechanisms.

Role of biomarkers in monitoring antiblastic cardiotoxicity

Early detection of anticancer drug-induced cardiotoxicity (CTX) has been evaluated by most international scientific cardiology and oncology societies. High expectations have been placed on the use of specific biomarkers. In recent years, conventional biomarkers and molecules of more recent interest have been tested and compared in the context of anticancer drug-related CTX. Encouraging results were obtained from studies on molecules of myocardial damage, such as troponin and markers of myocardial wall stress, including circulating natriuretic peptides, as well as from the assessment of the products of inflammation or circulating levels of free radicals. However, clear guidelines on their sensitivity, specificity, and accuracy are not yet available, and many challenges, such as the optimal time of assessing, optimal schedule for evaluation, optimal cut-off point for positivity with the highest level of specificity, and optimal comparability of different assays for the measurements, remain unresolved. Given the importance of having a reliable and accurate tool for monitoring anticancer drug-induced CTX, this review will focus on the available data on the most effective and widely used biomarkers and the studies that are currently underway that aim to identify the effectiveness of new approaches in this therapeutic setting.

SAFE-HEaRt: Rationale and Design of a Pilot Study Investigating Cardiac Safety of HER2 Targeted Therapy in Patients with HER2-Positive Breast Cancer and Reduced Left Ventricular Function

BACKGROUND

Human epidermal growth receptor 2 (HER2) targeted therapies have survival benefit in adjuvant and metastatic HER2 positive breast cancer but are associated with cardiac dysfunction. Current U.S. Food and Drug Administration recommendations limit the use of HER2 targeted agents to patients with normal left ventricular (LV) systolic function.

METHODS

The objective of the SAFE-HEaRt study is to evaluate the cardiac safety of HER2 targeted therapy in patients with HER2 positive breast cancer and mildly reduced left ventricular ejection fraction (LVEF) with optimized cardiac therapy. Thirty patients with histologically confirmed HER2 positive breast cancer (stage I-IV) and reduced LVEF (40% to 49%) who plan to receive HER2 targeted therapy for ≥3 months will be enrolled. Prior to initiation on study, optimization of heart function with beta-blockers and angiotensin converting enzyme inhibitors will be initiated. Patients will be followed by serial echocardiograms and cardiac visits during and 6 months after completion of HER2 targeted therapy. Myocardial strain and blood biomarkers, including cardiac troponin I and high-sensitivity cardiac troponin T, will be examined at baseline and during the study.

DISCUSSION

LV dysfunction in patients with breast cancer poses cardiac and oncological challenges and limits the use of HER2 targeted therapies and its oncological benefits. Strategies to prevent cardiac dysfunction associated with HER2 targeted therapy have been limited to patients with normal LVEF, thus excluding patients who may receive the highest benefit from those strategies. SAFE-HEaRt is the first prospective pilot study of HER2 targeted therapies in patients with reduced LV function while on optimized cardiac treatment that can provide the basis for clinical practice changes. The Oncologist 2017;22:518-525 IMPLICATIONS FOR PRACTICE: Human epidermal growth receptor 2 (HER2) targeted therapies have survival benefit in adjuvant and metastatic HER2 positive breast cancer but are associated with cardiac dysfunction. To our knowledge, SAFE-HEaRt is the first clinical trial that prospectively tests the hypothesis that HER2 targeted therapies may be safely administered in patients with mildly reduced cardiac function in the setting of ongoing cardiac treatment and monitoring. The results of this study will provide cardiac safety data and inform consideration of clinical practice changes in patients with HER2 positive breast cancer and reduced cardiac function, as well as provide information regarding cardiovascular monitoring and treatment in this population.

Loss of ErbB2-PI3K/Akt signaling prevents zinc pyrithione-induced cardioprotection during ischemia/reperfusion

OBJECTIVES

The purpose of this study was to determine if zinc homeostasis is affected during ischemia/reperfusion, if so, whether zinc pyrithione limits myocardial cell death and improves hemodynamics when administered as an adjunct to reperfusion and if ErbB receptor tyrosine kinases that are important for the long-term structural integrity of the heart are indispensable for reperfusion salvage.

METHODS

Isolated perfused rat hearts were subjected to 35min of global ischemia and reperfused for 120min to determine the relative intracellular zinc levels by TSQ staining. The hearts were reperfused in the presence of incremental concentrations of zinc pyrithione for the first 10min during reperfusion. Silencing or blockade of ErbB2 using a monoclonal antibody, ErbB2 kinase inhibition and PI3kinase inhibition was used to study their critical role in zinc pyrithione-induced cardioprotection.

RESULTS

We found that there was a profound decrease in intracellular zinc after ischemia/reperfusion resulting in increased apoptosis, caspase-3 activation, and infarct size. A dose-dependent reduction of infarct size with zinc pyrithione in the range of 5-20μmol/l (optimal protection was seen at 10μmol/l with infarct size of 16±2% vs. I/R vehicle, 33±2%, p<0.01). Increased TUNEL staining and caspase-3 activity observed after ischemia/reperfusion were attenuated by zinc pyrithione administration during the reperfusion. Moreover, this protection was sensitive to silencing and blockade of ErbB2, inhibition of ErbB2 kinase activity or PI3-kinase activity. Western blot analysis revealed that zinc pyrithione resulted in decreased caspase-3 activation, rapid stabilization of ErbB2/ErbB1 heterodimers, and increased activation of PI3K/Akt signaling cascade.

CONCLUSIONS

Zinc pyrithione attenuates lethal perfusion-induced injury in a manner that is reliant on ErbB2/PI3K/Akt activity.

The “Burden” of Malignancy in a Tertiary Hospital Intensive Cardiovascular Care Unit

<b><i>Objectives:</i></b> During the past decade, the most common causes of mortality and morbidity were cardiovascular diseases and malignancies. The aim of the current study was to describe the incidence, course of admission, and short-term (30-day) prognosis of patients with and without malignancy, admitted to a tertiary center intensive cardiovascular care unit (ICCU). <b><i>Methods:</i></b> A prospective observational study of 2,259 patients admitted to the ICCU was conducted between January 2014 and December 2015. Patients with malignancies (<i>n</i> = 256) were divided into 2 groups: those with solid and those with homogenous tumors. <b><i>Results:</i></b> The time of diagnosis was categorized into 3 patient groups: recent (<6 months), 59 patients (23%); late (6-24 months), 49 patients (19%), and very late (>24 months), 148 patients (58%). Those with a history of malignancy were older (73 ± 12 vs. 64 ± 15, <i>p</i> < 0.001) and were more likely to be female (<i>p</i> = 0.002). After using a multivariate logistic regression model analysis, no differences were found in therapeutic interventions and clinical outcomes, including major bleeding and acute renal failure, between patients with and without malignancies. <b><i>Conclusions:</i></b> Patients with a malignancy comprised about 10% of the entire ICCU population. While mortality was independently associated with advanced age, renal failure, and a diagnosis of ST-elevation myocardial infarction, malignancy alone was not found to be independently associated with a higher mortality rate at 30 days of follow-up.

Cardiotoxicity of the adjuvant trastuzumab in a Saudi population: clinical experience of a single institution

Purpose

Adjuvant trastuzumab is currently an internationally standard for the treatment of localised breast cancer that over express HER2 with the most adverse effect being cardiotoxicity. We conducted this study to evaluate the cardiac safety of trastuzumab in clinical practice.

Methods

This study is a retrospective observational single institutional study conducted in the Oncology Center of King Abdulla Medical City (KAMC), Makkah, Saudi Arabia, from June 2011 to January 2014. We evaluated the incidence of cardio toxicity and associated risk factors during adjuvant trastuzumab treatment.

Results

Of 57 patients, 20 patients (35%) exhibited cardiotoxicity. About 14% of patients had drop of left ventricular ejection fraction (LVEF) below 50%, whilst 10% and 15% drop of LVEF below their baseline levels were found in 30% and 5% of patients, respectively. About 98.3% of our patients have completed treatment, of whom 21% had a provisional interruption because of a fall in LVEF. A definitive trastuzumab discontinuation has been made in 1.75% of cases because of a nonregressive reduction in LVEF. Analysis of risk factors related to trastuzumab cardio toxicity found that patients older than 40 years were more likely to develop cardio toxicity compared to those younger than 40 years. This difference was statistically significant (p = 0.042).

Conclusion

In our study, the cardiac safety seems comparable with the literature data. Trastuzumab-related cardiotoxicity is manifested by an asymptomatic decrease in the LVEF and less commonly by clinical heart failure. Most instances are transient, asymptomatic and reversible.

Oncocardiology-Past, Present, and Future: A Review

Importance

Oncocardiology is a medical discipline that focuses on the identification, prevention, and treatment of cardiovascular complications related to cancer therapy. This discipline has gained interest from the cardiology community in recent years because of a remarkable increase in the number of cancer survivors and the proliferation of new cancer therapies causing cardiovascular complications, such as hypertension, heart failure, vascular complications, and cardiac arrhythmia. In this review, we provide historical perspectives, highlight new discoveries, and speculate on the opportunity created by merging the research interests and clinical practices of cardiology and oncology.

Observations

The old paradigm of anthracycline cardiotoxic effects is replaced by new insights that anthracycline targets topoisomerase II β to cause DNA double-strand breaks and a profound change in the transcriptome leading to the generation of reactive oxygen species and the development of mitochondriopathy. Prevention of anthracycline cardiotoxic effects should be based on inhibiting or degrading topoisomerase II β. New challenges were posed by the introduction of trastuzumab and tyrosine kinase inhibitors that revolutionized cancer therapy. The on-target cardiotoxic effects of trastuzumab were owing to a prosurvival benefit of Her2 that binds to neuregulin, whereas the off-target effect of multitargeted tyrosine kinase inhibitors may be mediated by disruption of the vascular endothelial growth factor signaling pathway or the stress-induced angiogenesis. Sensitive imaging techniques, such as global strain, and biomarkers have allowed for early detection of cardiotoxic effects. Early treatment with heart failure medications may be beneficial in preventing the development of late cardiotoxic effects.

Conclusions and Relevance

Close collaboration between cardiologists and oncologists is required to meet the demand of an increasing number of cancer survivors. New insights based on mechanistic studies or genetic discoveries will pave the way for better prevention, diagnosis, and treatment of cancer therapy-induced cardiovascular complications.

Trastuzumab-associated cardiac events in the Persephone trial

Background:

We report cardiac events in the Persephone trial which compares 6–12 months of adjuvant trastuzumab in women with confirmed HER2-positive, early-stage breast cancer.

Methods:

Clinical cardiac events were defined as any of the following: symptoms and/or signs of congestive heart failure (CHF) and new or altered CHF medication. In addition, left ventricular ejection fraction (LVEF) was measured at baseline and then 3 monthly for 12 months.

Results:

A total of 2500 patients, aged 22–82, were included: 1251 randomised to 12 months and 1249 to 6 months of trastuzumab treatment. A total of 93% (2335/2500) received anthracyclines, 49% of these (1136/2335) with taxanes. Cardiotoxicity delayed treatment in 6% of 12-month and 4% of 6-month patients (P=0.01), and stopped treatment early in 8% (96/1214) of 12-month and 4% (45/1216) of 6-month patients (P<0.0001). Between 7 and 12 months, more 12-month than 6-month patients had LVEFs<50% (8% vs 5% P=0.004). LVEFs showed quadratic change over time, and 6-month patients had a more rapid recovery (P=0.02). In a landmark analysis twice as many 12-month patients, free of cardiac events at 6 months, had cardiac problems in months 7–12 (6% (66/1046) vs 3% (29/1035) of 6-month patients (P=0.0002)). Lower baseline LVEF predicted more cardiac dysfunction in both arms (reference ⩾65%: 55 to <65% OR 1.61 (95% CI 1.26–2.04); <55% OR 5.22 (3.42–7.95)) as did increasing age (reference <50: 50–59 OR 1.58 (1.17–2.12), 60–69 OR 1.91 (1.42–2.57)) 70+ OR 2.72 (1.82–4.08)) and prior use of cardiac medication (OR 8.46 (4.69–15.25)). >3 cycles of anthracycline was associated with higher risk of cardiac events only for 12-month patients (OR 1.41 (1.04–1.90)), and not for 6-month patients (OR 1.28 (0.91–1.79)).

Conclusions:

We demonstrate significantly fewer cardiac events from 6 months of adjuvant trastuzumab compared with that from 12 months. This cardiac signal adds importance to the question of the optimum duration of adjuvant trastuzumab treatment. If 6 months is proven to have non-inferior outcomes to 12 months treatment, these data would support 6 months as the standard of care.

Early cardiac toxicity following adjuvant radiotherapy of left-sided breast cancer with or without concurrent trastuzumab

PURPOSE

To evaluate the influence of concurrent trastuzumab on the cardiotoxicity in patients receiving left-sided adjuvant radiotherapy.

MATERIALS AND METHODS

Medical records of stage I-III left-sided breast cancer patients, including 64 receiving concurrent trastuzumab with radiotherapy and 73 receiving radiotherapy alone were retrospectively reviewed. All of the patients had normal LVEF after adjuvant chemotherapy. Information of doses volume to cardiac structures was collected. Cardiac events were assessed according to CTC 2.0.

RESULTS

Median follow-up of LVEF and clinical assessment of cardiac function from the initiation of radiotherapy was 6.7 months (range 3-60.9) and 26 months (range 6.4-60.9), respectively. Grade 1 LVEF dysfunction occurred in 5 (7.8%) and 3 (4.1%) patients of the concurrent-trastuzumab and radiotherapy alone cohort, respectively. Trastuzumab was the only significant factor influencing absolute LVEF decrease in univariate analysis. In multivariate analysis of concurrent-trastuzumab cohort, IMC radiotherapy and start trastuzumab during radiotherapy were independent risk factors. For concurrent cohort, mean heart dose, as well as D10-D30, D50-D55, V5-V20 of the heart and D30-D45, D65-D75, V6-V15 of the LV were significantly higher in patients developing LVEF dysfunction.

CONCLUSIONS

Concurrent trastuzumab and left-sided radiotherapy is well tolerated in terms of cardiotoxicity in patients with normal baseline cardiac function after adjuvant chemotherapy. However, increases in mean dose and low-dose volume of cardiac structures are associated with a higher risk of acute LVEF dysfunction.

Role of Troponins I and T and N-Terminal Prohormone of Brain Natriuretic Peptide in Monitoring Cardiac Safety of Patients With Early-Stage Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer Receiving Trastuzumab: A Herceptin Adjuvant Study Cardiac Marker Substudy

Purpose Women receiving trastuzumab with chemotherapy are at risk for trastuzumab-related cardiac dysfunction (TRCD). We explored the prognostic value of cardiac markers (troponins I and T, N-terminal prohormone of brain natriuretic peptide [NT-proBNP]) to predict baseline susceptibility to develop TRCD. We examined whether development of cardiac end points or significant left ventricular ejection fraction (LVEF) drop was associated with markers' increases. Patients and Methods Cardiac marker assessments were coupled with LVEF measurements at different time points for 533 patients from the Herceptin Adjuvant (HERA) study who agreed to participate in this study. Patients with missing marker assessments were excluded, resulting in 452 evaluable patients. A primary cardiac end point was defined as symptomatic congestive heart failure of New York Heart Association class III or IV, confirmed by a cardiologist, and a significant LVEF drop, or death of definite or probable cardiac causes. A secondary cardiac end point was defined as a confirmed significant asymptomatic or mildly symptomatic LVEF drop. Results Elevated baseline troponin I (> 40 ng/L) and T (> 14 ng/L), occurring in 56 of 412 (13.6%) and 101 of 407 (24.8%) patients, respectively, were associated with an increased significant LVEF drop risk (univariate analysis: hazard ratio, 4.52; P < .001 and hazard ratio, 3.57; P < .001, respectively). Few patients had their first elevated troponin value recorded during the study (six patients for troponin I and 25 patients for troponin T). Two patients developed a primary and 31 patients a secondary cardiac end point (recovery rate of 74%, 23 of 31). For NT-proBNP, higher increases from baseline were seen in patients with significant LVEF drop. Conclusion Elevated troponin I or T before trastuzumab is associated with increased risk for TRCD. A similar conclusion for NT-proBNP could not be drawn because of the lack of a well-established elevation threshold; however, higher increases from baseline were seen in patients with TRCD compared with patients without.

Change in Pattern of HER2 Fluorescent in Situ Hybridization (FISH) Results in Breast Cancers Submitted for FISH Testing: Experience of a Reference Laboratory Using US Food and Drug Administration Criteria and American Society of Clinical Oncology and College of American Pathologists Guidelines

Purpose

In 1998, the US Food and Drug Administration (FDA) approved human epidermal growth factor receptor 2 (HER2) testing guidelines to determine eligibility for HER2-directed therapy (HDT) in breast cancer. ASCO and the College of American Pathologists published immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) HER2 testing guidelines in 2007 (AC2007) and updated these guidelines in 2013 (AC2013). We compared the HER2 FISH amplification frequency using these three guidelines.

Methods

Patient samples that were sent to the Mayo Clinic cytogenetics laboratory for FISH testing (n = 2,851; from November 2013 to October 2014) were analyzed. Frequency of HER2 FISH amplification was examined and impact of AC2013 assessed.

Results

IHC results were available for 1,922 patient samples (67.4%), 137 of which were from Mayo Clinic. Distribution was 2.4% IHC 0, 7.9% IHC 1+, 84.8% IHC 2+, and 2.5% IHC 3+. Among IHC 2+ patients, HER2 FISH positivity was 11.8% (FDA), 9.4% (AC2007), and 24.1% (AC2013). Overall, 11.8% (n = 339) were positive with a FISH ratio ≥ 2.0, 1.3% (n = 35) with a FISH ratio ≥ 2.0 despite a HER2 signal < 4.0, and 3.0% (n = 86) with HER2 signal ≥ 6.0 despite FISH ratio < 2.0. Among 405 patients (14.2%) who were initially considered FISH-equivocal (ratio < 2.0 with HER2 signal ≥ 4.0, but < 6.0; AC2013), use of an alternative chromosome 17 probe reassigned 212 (7.4% overall) patients to FISH-positive and 36 (1.3% overall) patients to FISH-negative, whereas 157 (5.5% overall) patients remained equivocal. Final HER2 positivity with AC2013 (23.6%) was increased (P < .001) compared with FDA (13.1%) and AC2007 (11%) guidelines.

Conclusion

In a reference laboratory cohort that was highly enriched for IHC 2+ patient samples, AC2013 guidelines led to a larger number of FISH-equivocal patients. Approximately one half of these FISH-equivocal patients (7.4% overall) became HER2-positive upon alternative FISH probe testing. However, these patients would not have participated in the pivotal HDT trials. Clinical utility data on HDT benefit in these patients and other special subsets are needed.

Timing of the negative effects of trastuzumab on cardiac mechanics after anthracycline chemotherapy

Trastuzumab (TZB) has been shown to be extremely effective in breast cancer patients over-expressing HER-2, but careful cardiac monitoring is required when TZB is administered with anthracyclines, since the combination can increase its toxicity. Myocardial deformation indexes associated with speckle tracking echocardiography (STE) have proven to be very sensitive in identifying early myocardial dysfunction. An observational, prospective study was designed to assess TZB-induced cardiac damage using STE in patients with HER-2 positive breast cancer who had been sequentially treated with TZB following epirubicin (EPI). Conventional echocardiographic parameters and STE deformation indexes (longitudinal, radial, and circumferential strain/strain rate and apical rotation) were analyzed at baseline, after each EPI treatment, and 1 week after every other dose of TZB administration until 1 year follow up, in order to focus on the timing and extent of myocardial impairment. In the forty-five enrolled patients, a reduction in subendocardial function after EPI treatment was observed by a significant impairment of the global longitudinal strain/strain rate (GLS/SR), while a significant increase in the activity of the subepicardial fibers was highlighted by an increase in apical rotation. After the second TZB dose, a sudden reduction of the apical rotation was seen, together with circumferential and radial strain/SR. Most importantly, the extent to which the apical rotation increased and decreased was found to strictly correlate with the GLS reduction at follow up. We found that after EPI therapy, subendocardial function was impaired, even while a compensatory increase in apical rotation occurred. Following TZB treatment, we observed impairment in apical rotation, which seems to be the first sign of global LV dysfunction predicting GLS reduction found at the end of treatment.

Organization and implementation of a cardio-oncology program

Considerable advances in cancer therapies in recent decades have reshaped the prognosis of cancer patients. There are now estimated to be over 20 million cancer survivors in the USA and Europe, numbers unimaginable a few years ago. However, this increase in survival, along with the aging of the patient population, has been accompanied by a rise in adverse cardiovascular effects, particularly when there is a previous history of heart disease. The incidence of cardiotoxicity continues to grow, which can compromise the effectiveness of cancer therapy. Cardiotoxicity associated with conventional therapies, especially anthracyclines and radiation, is well known, and usually leads to left ventricular dysfunction. However, heart failure represents only a fraction of the cardiotoxicity associated with newer therapies, which have diverse cardiovascular effects. There are few guidelines for early detection, prevention and treatment of cardiotoxicity of cancer treatments, and no well-established tools for screening these patients. Echocardiography is the method of choice for assessment of patients before, during and after cancer treatment. It therefore makes sense to adopt a multidisciplinary approach to these patients, involving cardiologists, oncologists and radiotherapists, collaborating in the development of new training modules, and performing clinical and translational research in a cardio-oncology program. Cardio-oncology is a new frontier in medicine and has emerged as a new medical subspecialty that concentrates knowledge, understanding, training and treatment of cardiovascular comorbidities, risks and complications in patients with cancer in a comprehensive approach to the patient rather than to the disease.

The role and clinical effectiveness of multimodality imaging in the management of cardiac complications of cancer and cancer therapy

With the increasing number of individuals living with a current or prior diagnosis of cancer, it is important for the cardiovascular specialist to recognize the various complications of cancer and its therapy on the cardiovascular system. This is true not only for established cancer therapies, such as anthracyclines, that have well established cardiovascular toxicities, but also for the new targeted therapies that can have "off target" effects in the heart and vessels. The purpose of this informational statement is to provide cardiologists, cardiac imaging specialists, cardio-oncologists, and oncologists an understanding of how multimodality imaging may be used in the diagnosis and management of the cardiovascular complications of cancer therapy. In addition, this document is meant to provide useful general information concerning the cardiovascular complications of cancer and cancer therapy as well as established recommendations for the monitoring of specific cardiotoxic therapies.

Cardio-Oncology: An Update on Cardiotoxicity of Cancer-Related Treatment

Through the success of basic and disease-specific research, cancer survivors are one of the largest growing subsets of individuals accessing the healthcare system. Interestingly, cardiovascular disease is the second leading cause of morbidity and mortality in cancer survivors after recurrent malignancy. This recognition has helped stimulate a collaboration between oncology and cardiology practitioners and researchers, and the portmanteau cardio-oncology (also known as onco-cardiology) can now be found in many medical centers. This collaboration promises new insights into how cancer therapies impact cardiovascular homeostasis and long-term effects on cancer survivors. In this review, we will discuss the most recent views on the cardiotoxicity related to various classes of chemotherapy agents and radiation. We will also discuss broadly the current strategies for treating and preventing cardiovascular effects of cancer therapy.

Targeted Agents for HER2-Positive Breast Cancer: Optimal Use in Older Patients

The HER2 gene is overexpressed in 15-20 % of all breast cancers. With the advent of HER2-directed therapies, HER2 overexpression is no longer considered an adverse prognostic factor. Despite significant improvements in clinical outcomes with the use of trastuzumab [herceptin (H)], women aged >65 years remain under-represented in most clinical trials. Cardiac safety in the elderly woman is a major concern because of pre-existing comorbidities. However, many studies suggest that elderly patients with HER2-positive disease derive the same benefit from trastuzumab as do their younger counterparts in both adjuvant and metastatic settings. Data are limited guiding safety and efficacy of other HER2 inhibitors such as pertuzumab and trastuzumab emtansine in elderly patients; however, in general, these drugs have a favorable toxicity profile.

[Early detection of cancer therapeutics-related cardiac dysfunction]

Anthracyclines and molecular targeted agents have improved prognosis of patients undergoing chemotherapeutics for malignancy. However, the use of these therapies is limited because of risk of cardiac toxicity. The severity of the cardiomyopathy can range from an asymptomatic left ventricular (LV) dysfunction to a severe congestive heart failure. Cardiomyopathy can be reversible or irreversible according to the type of chemotherapy, modality of administration and patient's characteristics. Several studies aimed to early detection and the evaluation of tools to characterize patients at risk to develop cardiac side effects in order to prevent severe LV dysfunction. According to this literature, it is recommended that initial assessment and follow-up of patients undergoing these chemotherapies be performed using troponin dosage, assessment of left ventricle ejection fraction and evaluation of LV myocardial deformation assessing LV global longitudinal strain.

Cardiac toxicity of trastuzumab in elderly patients with breast cancer

Breast cancer (BC) is diagnosed in ≥ 65 year old women in about half of cases. Experts currently recommend that systemic therapy is offered to elderly patients with BC, if, based on their overall conditions and life expectancy, it can be reasonably anticipated that the benefits will outweigh the risks of treatment. Like for young subjects, the monoclonal antibody against human epidermal growth factor receptor-2 (HER-2), trastuzumab, represents a valid therapeutic option when BC over-expresses this receptor. Unfortunately, administration of trastuzumab is associated with the occurrence of left ventricular dysfunction and chronic heart failure (CHF), possibly because of interference with the homeostatic functions of HER-2 in the heart. Registry-based, retrospective analyses have reported an incidence of CHF around 25% in elderly women receiving trastuzumab compared with 10%-15% in those not given any therapy for BC, and the risk of CHF has been estimated to be two-fold higher in > 60-65 year old trastuzumab users vs. non-users. Extremely advanced age and preexisting cardiac disease have been shown to predispose to trastuzumab cardiotoxicity. Therefore, selection of older patients for treatment with trastuzumab should be primarily based on their general status and the presence of comorbidities; previous chemotherapy, especially with anthracyclines, should be also taken into account. Once therapy has started, efforts should be made to ensure regular cardiac surveillance. The role of selected biomarkers, such as cardiac troponin, or new imaging techniques (three-dimension, tissue Doppler echocardiography, magnetic resonance imaging) is promising, but must be further investigated especially in the elderly. Moreover, additional studies are needed in order to better understand the mechanisms by which trastuzumab affects the old heart.

Cancer treatment-related cardiac toxicity: prevention, assessment and management

Cancer therapies, especially anthracyclines and monoclonal antibodies, have been linked with increased rates of cardiotoxicity. The development of some cardiac side effects happens over several months, and changes in ejection fraction can be detected long before permanent damage or disability occurs. Advanced heart failure could be averted with better and earlier detection. Methodologies for early detection of cardiac changes include stress echocardiograms, cardiac velocity measurements, radionuclide imaging, cardiac MRI and several potential biomarkers. Many agents have been described for prophylaxis of cardiac events precipitated by cancer therapy. Prophylactic use of beta-blockers and ACE inhibitors may be considered for use with trastuzumab in breast cancer as tolerated. Recovery of cardiac function is possible early after the injury from a cancer therapy. Late complications for coronary artery disease, hypertension and arrhythmia are underappreciated. Treatments for severe cancer therapy-related cardiac complications follow the existing paradigms for congestive heart failure and coronary artery disease, although outcomes for cancer patients differ from outcomes for non-cancer patients.

Cardiotoxicity of anticancer treatments: Epidemiology, detection, and management

Answer questions and earn CME/CNE Cancer and heart disease are the leading causes of morbidity and mortality in the industrialized world. Modern treatment strategies have led to an improvement in the chances of surviving a diagnosis of cancer; however, these gains can come at a cost. Patients may experience adverse cardiovascular events related to their cancer treatment or as a result of an exacerbation of underlying cardiovascular disease. With longer periods of survival, late effects of cancer treatment may become clinically evident years or decades after completion of therapy. Current cancer therapy incorporates multiple agents whose deleterious cardiac effects may be additive or synergistic. Cardiac dysfunction may result from agents that can result in myocyte destruction, such as with anthracycline use, or from agents that appear to transiently affect left ventricular contractility. In addition, cancer treatment may be associated with other cardiac events, such as severe treatment-induced hypertension and vasospastic and thromboembolic ischemia, as well as rhythm disturbances, including QTc prolongation, that may be rarely life-threatening. Early and late effects of chest radiation can lead to radiation-induced heart disease, including pericardial disease, myocardial fibrosis, cardiomyopathy, coronary artery disease, valvular disease, and arrhythmias, in the setting of myocardial fibrosis. The discipline of cardio-oncology has developed in response to the combined decision making necessary to optimize the care of cancer patients, whether they are receiving active treatment or are long-term survivors. Strategies to prevent or mitigate cardiovascular damage from cancer treatment are needed to provide the best cancer care. This review will focus on the common cardiovascular issues that may arise during or after cancer therapy, the detection and monitoring of cardiovascular injury, and the best management principles to protect against or minimize cardiotoxicity during the spectrum of cancer treatment strategies. CA Cancer J Clin 2016;66:309-325. © 2016 American Cancer Society.

Heart failure in chemotherapy-related cardiomyopathy: Can exercise make a difference?

Medical therapies in oncology have resulted in better survival resulting in a large population who are at risk of early and late cardiac complications of chemotherapy. Cardiotoxicity related to chemotherapy can manifest decades after treatment with a threefold higher mortality rate as compared to idiopathic dilated cardiomyopathy. The leading cause of death in cancer survivors seems to be cardiac. Early detection and intervention could prevent progression of heart failure to end stage disease requiring advanced therapies such as implantation of ventricular assist devices or cardiac transplantation. This review focuses on the role of exercise in cardioprotection in this population. The current practice of depending on ejection fraction for diagnosis of heart failure is suboptimal to detect subclinical disease. It is also important to diagnose and treat early diastolic dysfunction as this tends to lead to heart failure with preserved ejection fraction. Hence we suggest an algorithm here that is based on using strain rate and tissue Doppler imaging modalities to detect subclinical systolic and diastolic dysfunction. Further research is warranted in terms of defining exercise prescriptions in this population. Human studies with multicenter participation in randomized controlled trials should be done to elucidate the intricacies of aerobic exercise intervention in cardiotoxicity dependent heart failure. It is also necessary to assess the utility of exercise interventions in the different chemotherapeutic regimens as they impact the outcomes.

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The need for exercise prescription to prevent cardiotoxicity in chemotherapy patients

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The molecular basis of exercise as an intervention

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Summary of existing evidence

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Need for further studies on the role of exercise in different chemotherapeutic regimens

Late Cardiotoxicity: Issues for Childhood Cancer Survivors

OPINION STATEMENT

Cardiovascular-related morbidity is a substantial health burden in survivors of childhood cancers. This burden is gaining importance as this population increases through advancements in therapy. Anthracyclines are commonly used agents that are known to cause late cardiotoxicity. Cardiotoxicity is also increased by other risk factors, such as concurrent radio- or chemotherapy, younger age at diagnosis, female sex, comorbidities, lifestyle factors, and genetic factors, such as hemochromatosis gene mutations. Treatment of late cardiotoxicity depends on the type of cardiac abnormalities and consists of pharmacotherapy, mechanical support, or heart transplantation. Because cardiotoxicity is progressive and often irreversible, prevention, risk reduction, and early detection are of utmost importance. The cardioprotectant dexrazoxane decreases anthracycline cardiotoxicity. Screening for other risk factors at the time of diagnosis may identify risk that when present, if used to tailor therapy, may reduce the severity of cardiac damage. The effects of exercise and other lifestyle changes in reducing the cardiovascular diseases in cancer survivors are unclear. However, it may be beneficial to encourage survivors to engage in physical activity tailored to survivor medical status, but with close monitoring.

The Role of Biomarkers in Decreasing Risk of Cardiac Toxicity after Cancer Therapy

With the improvement of cancer therapy, survival related to malignancy has improved, but the prevalence of long-term cardiotoxicity has also increased. Cancer therapies with known cardiac toxicity include anthracyclines, biologic agents (trastuzumab), and multikinase inhibitors (sunitinib). The most frequent presentation of cardiac toxicity is dilated cardiomyopathy associated with poorest prognosis. Monitoring of cardiac toxicity is commonly performed by assessment of left ventricular (LV) ejection fraction, which requires a significant amount of myocardial damage to allow detection of cardiac toxicity. Accordingly, this creates the impetus to search for more sensitive and reproducible biomarkers of cardiac toxicity after cancer therapy. Different biomarkers have been proposed to that end, the most studied ones included troponin release resulting from cardiomyocyte damage and natriuretic peptides reflecting elevation in LV filling pressure and wall stress. Increase in the levels of troponin and natriuretic peptides have been correlated with cumulative dose of anthracycline and the degree of LV dysfunction. Troponin is recognized as a highly efficient predictor of early and chronic cardiac toxicity, but there remains some debate regarding the clinical usefulness of the measurement of natriuretic peptides because of divergent results. Preliminary data are available for other biomarkers targeting inflammation, endothelial dysfunction, myocardial ischemia, and neuregulin-1. The purpose of this article is to review the available data to determine the role of biomarkers in decreasing the risk of cardiac toxicity after cancer therapy.

Improving the preclinical models for the study of chemotherapy-induced cardiotoxicity: a Position Paper of the Italian Working Group on Drug Cardiotoxicity and Cardioprotection

Although treatment for heart failure induced by cancer therapy has improved in recent years, the prevalence of cardiomyopathy due to antineoplastic therapy remains significant worldwide. In addition to traditional mediators of myocardial damage, such as reactive oxygen species, new pathways and target cells should be considered responsible for the impairment of cardiac function during anticancer treatment. Accordingly, there is a need to develop novel therapeutic strategies to protect the heart from pharmacologic injury, and improve clinical outcomes in cancer patients. The development of novel protective therapies requires testing putative therapeutic strategies in appropriate animal models of chemotherapy-induced cardiomyopathy. This Position Paper of the Working Group on Drug Cardiotoxicity and Cardioprotection of the Italian Society of Cardiology aims to: (1) define the distinctive etiopatogenetic features of cardiac toxicity induced by cancer therapy in humans, which include new aspects of mitochondrial function and oxidative stress, neuregulin-1 modulation through the ErbB receptor family, angiogenesis inhibition, and cardiac stem cell depletion and/or dysfunction; (2) review the new, more promising therapeutic strategies for cardioprotection, aimed to increase the survival of patients with severe antineoplastic-induced cardiotoxicity; (3) recommend the distinctive pathological features of cardiotoxicity induced by cancer therapy in humans that should be present in animal models used to identify or to test new cardioprotective therapies.

Cardiotoxicity associated with targeted cancer therapies

Compared with traditional chemotherapy, targeted cancer therapy is a novel strategy in which key molecules in signaling pathways involved in carcinogenesis and tumor spread are inhibited. Targeted cancer therapy has fewer adverse effects on normal cells and is considered to be the future of chemotherapy. However, targeted cancer therapy-induced cardiovascular toxicities are occasionally critical issues in patients who receive novel anticancer agents, such as trastuzumab, bevacizumab, sunitinib and imatinib. The aim of this review was to discuss these most commonly used drugs and associated incidence of cardiotoxicities, including left ventricular dysfunction, heart failure, hypertension and thromboembolic events, as well as summarize their respective molecular mechanisms of cardiovascular adverse effects.

Heart Failure Therapies for End-Stage Chemotherapy-Induced Cardiomyopathy

With ongoing advancements in cancer-related treatments, the number of cancer survivors continues to grow globally, with numbers in the United States predicted to reach 18 million by 2020. As a result, it is expected that a greater number of patients will present with chemotherapy-related side effects. One entity in particular, chemotherapy-related cardiomyopathy (CCMP), is a known cardiotoxic manifestation associated with agents such as anthracyclines, trastuzumab, and tyrosine kinase inhibitors. Although such effects have been described in the medical literature for decades, concrete strategies for screening, prevention, and management of CCMP continue to be elusive owing to limited studies. Late recognition of CCMP is associated with a poorer prognosis, including a lack of clinical response to pharmacologic therapy, and end-stage heart failure. A number of advanced cardiac therapies, including cardiac resynchronization therapy, ventricular assist devices, and orthotopic cardiac transplantation, are available to for end-stage heart failure; however, the role of these therapies in CCMP is unclear. In this review, management of end-stage CCMP with the use of advanced therapies and their respective effectiveness are discussed, as well as clinical characteristics of patients undergoing these treatments. The relative paucity of data in this field highlights the importance and need for larger-scale longitudinal studies and long-term registries tracking the outcomes of cancer survivors who have received cardiotoxic cancer therapy to determine the overall incidence of end-stage CCMP, as well as prognostic factors that will ultimately guide such patients toward receiving appropriate end-stage care.

Cardio-Oncology Training: A Proposal From the International Cardioncology Society and Canadian Cardiac Oncology Network for a New Multidisciplinary Specialty

There is an increasing awareness and clinical interest in cardiac safety during cancer therapy as well as in optimally addressing cardiac issues in cancer survivors. Although there is an emerging expertise in this area, known as cardio-oncology, there is a lack of organization in the essential components of contemporary training. This proposal, an international consensus statement organized by the International Cardioncology Society and the Canadian Cardiac Oncology Network, attempts to marshal the important ongoing efforts for training the next generation of cardio-oncologists. The necessary elements are outlined, including the expectations for exposure necessary to develop adequate training. There should also be a commitment to local, regional, and international education and research in cardio-oncology as a requirement for advancement in the field.

Risk of Congestive Heart Failure in Early Breast Cancer Patients Undergoing Adjuvant Treatment With Trastuzumab: A Meta-Analysis

BACKGROUND

The use of trastuzumab has proven to be a successful strategy in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer; however, it is associated with an increased risk of cardiac dysfunction. We performed an up-to-date, comprehensive meta-analysis to clarify the risk of congestive heart failure (CHF) in patients with early breast cancer receiving different durations of adjuvant trastuzumab with the longest-term follow-up.

METHODS

Eligible studies included randomized control trials of HER2-positive early breast cancer patients with or without trastuzumab in adjuvant chemotherapy. Adequate reporting of CHF data were required for inclusion. Statistical analyses were conducted to calculate the overall incidence, relative risk (RR), and 95% confidence interval (CI) by use of a fixed-effects model.

RESULTS

Six randomized control trials including 18,111 patients were identified. The overall incidence of high-grade CHF in patients treated with trastuzumab versus placebo was 1.44% (95% CI, 0.79%-2.64%) and the RR was 3.19 (95% CI, 2.03-5.02; p < .00001). In subgroup analysis, the difference in CHF incidence failed to achieve significance. The RR for 8 mg/kg trastuzumab (high dose) was greater than that for 4 mg/kg (low dose) (RR, 6.79, 95% CI, 2.03-22.72, p = .0001; versus RR, 2.64; 95% CI, 1.61-4.32; p = .002). Additionally, higher RRs were observed for patients receiving trastuzumab for 1 year (RR, 3.29; 95% CI, 2.07-5.25) and 2 years (RR, 9.54; 95%CI, 2.19-41.43), but not 9 weeks (RR, 0.50; 95% CI, 0.05-5.49) compared with control groups. No evidence of publication bias was observed.

CONCLUSION

Adjuvant trastuzumab therapy was strongly associated with an increased risk of significant CHF in patients with early breast cancer, particularly in 2-year use.

IMPLICATIONS FOR PRACTICE

This comprehensive meta-analysis evaluated the risk of congestive heart failure with a usage profile of adjuvant trastuzumab in patients with early breast cancer. Before initiating treatment with trastuzumab, a risk-benefit analysis for individual patients should be critically evaluated, considering that the prognosis is closely related to drug dose and duration of use. Cardiac function should be monitored throughout the treatment period and also during follow-up. Thus, early identification of trastuzumab-related cardiac dysfunction can allow effective medical intervention, elimination of symptoms, recovery of function, and continuation of trastuzumab therapy.

The Clinical Efficacy and Cardiotoxicity of Fixed-Dose Monthly Trastuzumab in HER2-Positive Breast Cancer: A Single Institutional Analysis

Objective

Trastuzumab-containing treatment regimens have been shown to improve survival outcomes in HER2-positive breast cancer (BC). It is much easier to infuse a fixed one-vial dose to every patient on a regular schedule in the general clinical setting. The aims of this study were evaluating the efficacy of a 440 mg fixed-dose of trastuzumab administered on a monthly infusion schedule, and the risk factors for cardiac events.

Patients and methods

We retrospectively reviewed data from 300 HER2-positive BC patients in our institute: 208 were early-stage BC patients undergoing adjuvant trastuzumab treatment, and 92 were metastatic BC patients treated with trastuzumab infusions until disease progression. There were 181 patients receiving regular trastuzumab infusions every 3 weeks (Q3W; 8 mg/kg loading dose followed by 6 mg/kg every 3 weeks), and the other 119 patients were treated monthly with a fixed 440 mg dose (QM; fixed 440 mg every 4 weeks).

Results

The medians of progression-free survival (PFS) and overall survival (OS) in the adjuvant setting were not reached in both treatment groups. In the metastatic setting, there was no significant difference between groups in PFS or OS. The median time to significant cardiovascular (CV) dysfunction was 4.54 months. The incidence of congestive heart failure requiring medication in our cohort was 3.4%.

Conclusion

In our study, we found that fixed-dose monthly trastuzumab was feasible and effective. In addition, the CV risk was not higher with the fixed-dose protocol. This treatment modality could lower the cost and was easier to implement in clinical practice. Larger prospective randomized studies with longer-term follow up are needed to confirm our results.

Update on cardiotoxicity of anti-cancer treatments

BACKGROUND AND AIMS

Anti-cancer treatments markedly improved the prognosis of patients, but unfortunately might be hampered by cardiotoxicity. Both symptomatic and asymptomatic clinical forms of heart failure have been reported, which may be reversible or irreversible. The aim of this review is to provide an overview of the antineoplastic agents associated with cardiac toxicity and of the available diagnostic techniques.

METHODS AND METHODS

This narrative review is based on material from MEDLINE and PUBMED up to November 2015. We looked at the terms antineoplastic drugs and cardiac toxicity in combination with echocardiography, troponins, cardiac magnetic resonance, and positron emission tomography.

RESULTS

Anthracyclines, monoclonal antibodies, fluoropyrimidines, taxanes, alkylating agents, vinka alkaloids were reported to induce different clinical manifestations of cardioxicity. Chest radiotherapy is also associated with various forms of cardiac damage, which are indistinguishable from those found in patients with heart disease of other aetiologies and that may even appear several years after administration. Among diagnostic techniques, echocardiography is a noninvasive, cost-effective, and widely available imaging tool. Nuclear imaging and cardiac magnetic resonance may be used but are not so widely available and are more difficult to perform. Finally, some biomarkers, such as troponins, may be used to evaluate cardiac damage, but establishing the optimal timing of troponin assessment remains unclear and defining the cut-off point for positivity is still an important goal.

CONCLUSIONS

Cardiotoxicity of anti-cancer treatments is associated with development of heart failure. Novel diagnostic tools might be relevant to early recognize irreversible forms cardiac diseases.

Anthracycline or trastuzumab-related cardiotoxicity: do we have a predictive biomarker?

Chemotherapy-induced cardiotoxicity, is a well-known and potentially serious complication strongly impacting the quality of life and overall survival of breast cancer patients. The current diagnostic approach to detect cardiac damage is the estimation of left ventricular ejection fraction by echocardiography. However, this approach exhibits less sensitivity toward early prediction of cardiomyopathy, not allowing for preventive strategies. Measurement of serum cardiac-specific biomarkers can be a valid diagnostic tool for identifying patients prone to developing cardiotoxocity and in whom closer cardiac monitoring and preventive strategies are pivotal. In this article, we review work done on biomarkers in recent years, with an emphasis on troponin and B-type natriuretic peptide, which are currently the most studied in this field. We also briefly discuss current and emerging imaging techniques for early detection of cardiomyopathy.

Cardiac safety of simultaneous anti-HER2 and anthracycline therapy

A long established oncological dogma requires that trastuzumab should not be given in combination with anthracyclines due to excessive synergistic cardiac morbidity. However, trastuzumab has been recently granted a license in the neoadjuvant setting with concurrent anthracylines. We discuss the role of anti-HER2 agents in breast cancer and their associated toxicities. Anthracycline chemotherapies are a central component of most adjuvant and neoadjuvant breast cancer regimens. Cardiac toxicity due to anthracyclines is explored. Finally, in this article, we will discuss the evidence for concurrent administration of anthracyclines and HER2-targeted agents.

Cardiomyopathy Associated With Targeted Therapy for Breast Cancer

BACKGROUND

Chemotherapeutic agents directed against human epidermal growth factor receptor 2 (HER-2) have significantly improved the prognosis of patients who are positive for this receptor. However, cardiomyopathy remains as a common adverse effect of using these agents.

MATERIALS AND METHODS

Literature search was conducted via PubMed using the keywords of "Trastuzumab Cardiomyopathy," "Lapatinib Cardiomyopathy" and "Pertuzumab Cardiomyopathy," which provided 104 results. These articles were then screened for relevance to the targeted subject based on their title and abstracts. Case reports and articles that were not discussing any aspect of cardiomyopathy secondary to targeted therapy for breast cancer and articles not in English were eliminated. After elimination, a bibliography search among selected articles was done and a total of 46 articles were identified. The collected articles were then meticulously analyzed and summarized.

RESULTS

The use of human epidermal growth factor receptor 2 (HER-2) receptor targeted chemotherapy in breast cancer is limited because of a higher incidence (19-22%) of cardiomyopathy. The incidence of cardiomyopathy is not dose dependent and in most cases it is reversible after discontinuation of the drug and treatment with heart failure medications. Severe adverse outcomes including death or permanent disability are rare.

CONCLUSION

HER-2 targeted chemotherapy for breast cancer has a higher incidence of associated reversible cardiomyopathy. Patients should be monitored by serial echocardiography starting at the beginning of the treatment and followed by every 3 months until the completion of chemotherapy. Co-ordination between oncologists and cardiologists is needed to develop evidence-based protocols to prevent, identify, monitor and treat trastuzumab-induced cardiomyopathy.