Biomarkers and cardiovascular outcomes in chimeric antigen receptor T-cell therapy recipients.

AIMS: Chimeric antigen receptor T-cell therapy (CAR-T) harnesses a patient's immune system to target cancer. There are sparse existing data characterizing death outcomes after CAR-T-related cardiotoxicity. This study examines the association between CAR-T-related severe cardiovascular events (SCE) and mortality. METHODS AND RESULTS: From a multi-centre registry of 202 patients receiving anti-CD19 CAR-T, covariates including standard baseline cardiovascular and cancer parameters and biomarkers were collected. Severe cardiovascular events were defined as a composite of heart failure, cardiogenic shock, or myocardial infarction. Thirty-three patients experienced SCE, and 108 patients died during a median follow-up of 297 (interquartile range 104-647) days. Those that did and did not die after CAR-T were similar in age, sex, and prior anthracycline use. Those who died had higher peak interleukin (IL)-6 and ferritin levels after CAR-T infusion, and those who experienced SCE had higher peak IL-6, C-reactive protein (CRP), ferritin, and troponin levels. The day-100 and 1-year Kaplan-Meier overall mortality estimates were 18% and 43%, respectively, while the non-relapse mortality (NRM) cumulative incidence rates were 3.5% and 6.7%, respectively. In a Cox model, SCE occurrence following CAR-T was independently associated with increased overall mortality risk [hazard ratio (HR) 2.8, 95% confidence interval (CI) 1.6-4.7] after adjusting for age, cancer type and burden, anthracycline use, cytokine release syndrome grade ≥ 2, pre-existing heart failure, hypertension, and African American ancestry; SCEs were independently associated with increased NRM (HR 3.5, 95% CI 1.4-8.8) after adjusting for cancer burden. CONCLUSION: Chimeric antigen receptor T-cell therapy recipients who experience SCE have higher overall mortality and NRM and higher peak levels of IL-6, CRP, ferritin, and troponin.

Myocarditis Surveillance in Patients with Advanced Melanoma on Combination Immune Checkpoint Inhibitor Therapy: The Memorial Sloan Kettering Cancer Center Experience.

This letter to the editor describes myocarditis screening among patients undergoing combination immune checkpoint inhibitor therapy, in light of the consensus document from the Checkpoint Inhibitor Safety Working Group.

Cardiac outcomes of trastuzumab therapy in patients with HER2-positive breast cancer and reduced left ventricular ejection fraction.

PURPOSE: Asymptomatic decline in left ventricular ejection fraction (LVEF) or heart failure (HF) occurs in up to 25% of patients treated with trastuzumab and can result in incomplete breast cancer therapy. The cardiac safety of continuing trastuzumab in patients with asymptomatic LVEF decline is unknown. We report the cardiac outcomes of patients treated with trastuzumab after a significant asymptomatic LVEF decline. METHODS: Patients with HER2-positive breast cancer and asymptomatic LVEF decline to < 50% during trastuzumab were identified from an institutional echocardiogram database. Patients who received trastuzumab with a LVEF < 50% were classified as the continued group, whereas patients who had trastuzumab held until LVEF improved to ≥ 50% or who had trastuzumab permanently discontinued were classified as the interrupted group. Cardiac events were defined as HF (New York Heart Association class III-IV) or cardiovascular death. RESULTS: Sixty patients were included; the median age was 54 years. In 23 patients who continued trastuzumab, 14 (61%) tolerated trastuzumab without a cardiac event, 6 (26%) developed worsening LVEF (range 25-42%) leading to trastuzumab discontinuation, and three (13%) developed a cardiac event (1 HF, 2 possible/probable cardiovascular deaths). In 37 patients with interrupted trastuzumab, 15 (41%) were re-challenged with trastuzumab after LVEF improved to > 50%, 21 (57%) were not re-challenged, and one (3%) developed HF. More patients in the continued trastuzumab group had metastatic disease (39% vs. 5%, p = 0.002). The final LVEF after median follow-up of 633 days was similar between patients with trastuzumab continuation versus interruption (54% vs. 56%, p = 0.29). CONCLUSION: Continuation of trastuzumab after an asymptomatic LVEF decline to < 50% in patients who are expected to benefit from additional anti-HER2 therapy is a promising approach that warrants further investigation.

Development and Validation of a Clinical Score for Cardiovascular Risk Stratification of Long-Term Childhood Cancer Survivors.

BACKGROUND: Long-term childhood cancer survivors (CCS) are at increased risk of adverse cardiovascular events; however, there is a paucity of risk-stratification tools to identify those at higher-than-normal risk. SUBJECTS, MATERIALS, AND METHODS: This was a population-based study using data from the Surveillance, Epidemiology, and End Results Program (1973-2013). Long-term CCS (age at diagnosis ≤19 years, survival ≥5 years) were followed up over a median time period of 12.3 (5-40.9) years. Independent predictors of cardiovascular mortality (CVM) were combined into a risk score, which was developed in a derivation set (n = 22,374), and validated in separate patient registries (n = 6,437). RESULTS: In the derivation registries, older age at diagnosis (≥10 years vs. reference group of 1-5 years), male sex, non-white race, a history of lymphoma, and a history of radiation were independently associated with an increased risk of CVM among long-term CCS (p < .05). A risk score derived from this model (Childhood and Adolescence Cancer Survivor CardioVascular score [CHACS-CV], range: 0-8) showed good discrimination for CVM (Harrell's C-index [95% confidence interval (CI)]: 0.73 [0.68-0.78], p < .001) and identified a high-risk group (CHACS-CV ≥6), with cumulative CVM incidence over 30 years of 6.0% (95% CI: 4.3%-8.1%) versus 2.6% (95% CI: 1.8%-3.7%), and 0.7% (95% CI: 0.5%-1.0%) in the mid- (CHACS-CV = 4-5) and low-risk groups (CHACS-CV ≤3), respectively (plog-rank < .001). In the validation set, the respective cumulative incidence rates were 4.7%, 3.1%, and 0.8% (plog-rank < .001). CONCLUSION: We propose a simple risk score that can be applied in everyday clinical practice to identify long-term CCS at increased cardiovascular risk, who may benefit from early cardiovascular screening, and risk-reduction strategies. IMPLICATIONS FOR PRACTICE: Childhood cancer survivors (CCS) are known to be at increased cardiovascular risk. Currently available prognostic tools focus on treatment-related adverse events and late development of congestive heart failure, but there is no prognostic model to date to estimate the risk of cardiovascular mortality among long-term CCS. A simple clinical tool is proposed for cardiovascular risk stratification of long-term CCS based on easily obtainable information from their medical history. This scoring system may be used as a first-line screening tool to assist health care providers in identifying those who may benefit from closer follow-up and enable timely deployment of preventive strategies.

Myocarditis Associated with Immune Checkpoint Inhibitors: An Expert Consensus on Data Gaps and a Call to Action.

Immune checkpoint inhibitors (ICIs) have transformed the treatment landscape for cancer. Due to the mechanism of action of ICIs, inflammatory reactions against normal tissue were an anticipated side effect of these agents; these immune-related adverse events have been documented and are typically low grade and manageable. Myocarditis has emerged as an uncommon but potentially life-threatening adverse reaction in patients treated with ICIs. Assessment and characterization of ICI-associated myocarditis is challenging because of its low incidence and protean manifestations. Nevertheless, the seriousness of ICI-associated myocarditis justifies a coordinated effort to increase awareness of this syndrome, identify patients who may be at risk, and enable early diagnosis and appropriate treatment. The "Checkpoint Inhibitor Safety Working Group," a multidisciplinary committee of academic, industry, and regulatory partners, convened at a workshop hosted by Project Data Sphere, LLC, on December 15, 2017. This meeting aimed to evaluate the current information on ICI-associated myocarditis, determine methods to collect and share data on this adverse reaction, and establish task forces to close the identified knowledge gaps. In this report, we summarize the workshop findings and proposed steps to address the impact of ICI-associated myocarditis in patients with cancer.

Cardiac Safety of Dual Anti-HER2 Therapy in the Neoadjuvant Setting for Treatment of HER2-Positive Breast Cancer.

BACKGROUND: Trastuzumab and pertuzumab are approved for the neoadjuvant treatment of human epidermal growth receptor 2 (HER2)-positive breast cancer, but cardiac safety data is limited. We report the cardiac safety of dose-dense doxorubicin and cyclophosphamide (AC) followed by paclitaxel, trastuzumab, and pertuzumab (THP) in the neoadjuvant setting followed by adjuvant trastuzumab-based therapy. METHODS: Fifty-seven patients treated with neoadjuvant dose-dense AC-THP followed by adjuvant trastuzumab-based therapy between September 1, 2013, and March 1, 2015, were identified. The primary outcome was cardiac event rate, defined by heart failure (New York Heart Association [NYHA] class III/IV) or cardiac death. Patients underwent left ventricular ejection fraction (LVEF) monitoring at baseline, after AC, and serially during 1 year of anti-HER2 therapy. RESULTS: The median age was 46 years (range 26-68). Two (3.5%) patients developed NYHA class III/IV heart failure 5 and 9 months after initiation of trastuzumab-based therapy, leading to permanent discontinuation of anti-HER2 treatment. Seven (12.3%) patients developed a significant LVEF decline (without NYHA class III/IV symptoms). The median LVEF was 65% (range 55%-75%) at baseline and 64% (range 53%-72%) after AC, and decreased to 60% (range 35%-70%), 60% (range 23%-73%), 61% (range 25%-73%), and 58% (range 28%-66%) after 3, 6, 9, and 12 months (± 6 weeks) of trastuzumab-based therapy. CONCLUSION: The incidence of NYHA class III/IV heart failure after neoadjuvant AC-THP (followed by adjuvant trastuzumab-based therapy) is comparable to rates reported in trials of sequential doxorubicin and trastuzumab. Our findings do not suggest an increased risk of cardiotoxicity from trastuzumab plus pertuzumab following a doxorubicin-based regimen. IMPLICATIONS FOR PRACTICE: Dual anti-human epidermal growth receptor 2 (HER2) therapy with trastuzumab and pertuzumab combined with standard chemotherapy has received accelerated approval for the neoadjuvant treatment of stage II-III HER2-positive breast cancer. Cardiac safety data for trastuzumab and pertuzumab in this setting are limited to clinical trials that utilized epirubicin-based chemotherapy. Formalized investigations into the cardiac safety of trastuzumab and pertuzumab with doxorubicin- (rather than epirubicin) based regimens are important because these regimens are widely used for the adjuvant and neoadjuvant treatment of breast cancer. The known role of HER2 signaling in the physiological adaptive responses of the heart provides further rationale for study on the potential cardiotoxicity of dual anti-HER2 blockade. Findings from this retrospective study provide favorable preliminary data on the cardiac safety of trastuzumab and pertuzumab in combination with a regimen of neoadjuvant doxorubicin and cyclophosphamide followed by paclitaxel, one of the preferred breast cancer treatment regimens, according to the National Comprehensive Cancer Network.

Cardiac safety of non-anthracycline trastuzumab-based therapy for HER2-positive breast cancer.

PURPOSE: Trastuzumab improves overall survival for women with HER2-positive breast cancer but is associated with cardiotoxicity, especially when administered after anthracyclines. Use of non-anthracycline trastuzumab-based regimens is rising, particularly for patients with low-risk disease or with multiple cardiovascular risk factors. We performed a single-center retrospective cohort study to assess the cardiac safety of trastuzumab without anthracyclines outside of a clinical trial setting. METHODS: A retrospective chart review was conducted of patients with HER2-positive early-stage breast cancer receiving non-anthracycline trastuzumab-based therapy between January 2010 and June 2014. Cardiovascular risk factors, left ventricular ejection fraction (LVEF), and treatment interruption data were collected. The primary outcome was a cardiac event (CE), defined by New York Heart Association class III or IV heart failure or cardiac death. The secondary outcome was a significant asymptomatic decline of LVEF (>10% to <55% or >16% from baseline). RESULTS: A total of 165 patients were identified with a median age of 59 years (range 32-85 years). Seventy (42%) had hypertension, 52 (32%) had hyperlipidemia, 29 (18%) had diabetes, and 5 (3%) had coronary artery disease. All patients had a LVEF >50% (median 67%; range 50-80%) at baseline. Two (1.2%) patients with multiple cardiovascular risk factors developed a CE. After discontinuation of trastuzumab, both patients had recovery of LVEF to >50% and resolution of heart failure symptoms. Ten (6.1%) patients developed significant asymptomatic LVEF decline during trastuzumab therapy. CONCLUSIONS: The overall incidence of symptomatic heart failure and asymptomatic LVEF decline among patients receiving trastuzumab without anthracyclines remains low. These findings suggest that less intensive cardiac monitoring may be appropriate during trastuzumab therapy without anthracyclines.

Cardiac Safety of Paclitaxel Plus Trastuzumab and Pertuzumab in Patients With HER2-Positive Metastatic Breast Cancer.

INTRODUCTION: Myocardial strain imaging and blood biomarkers have been proposed as adjuncts to left ventricular ejection fraction (LVEF) monitoring for the early detection of cardiotoxicity during cancer therapy. We report the results of a preplanned cardiac safety analysis of global longitudinal strain (GLS), and troponin-I (TnI) and brain natriuretic peptide (BNP) levels in the phase II study of paclitaxel, trastuzumab, and pertuzumab (THP) for metastatic HER2-positive breast cancer. PATIENTS AND METHODS: Patients with 0-1 lines of prior therapy were treated with weekly paclitaxel (80 mg/m(2)) plus trastuzumab (8 mg/kg loading dose followed by 6 mg/kg) and pertuzumab (840 mg loading dose followed by 420 mg) every 3 weeks. Exploratory endpoints were GLS measured with speckle-tracking echocardiography every 3 months and TnI and BNP levels measured every 6 weeks (immediately pre- and postchemotherapy infusion) at 6 time points. RESULTS: Sixty-seven of 69 enrolled patients were treated with THP: 19 (28%) had hypertension, 8 (12%) had diabetes, 11 (16%) had hyperlipidemia, and 26 (38%) had smoking history. After a median follow-up of 21 months (range: 3-38 months), no patients developed symptomatic heart failure. Two patients (3.0%) experienced asymptomatic LVEF decline (grade 2). The mean GLS (±SD) was 19% ± 2% (baseline), 19% ± 2% (month 6), and 19% ± 3% (month 12). Detectable TnI (>0.06 ng/mL) and elevated BNP (>100 pg/mL) levels were observed in 3 (4.3%) and 2 (3.0%) patients, respectively, but were not associated with LVEF decline. CONCLUSION: The absence of any significant changes in GLS and cardiac biomarkers (TnI and BNP) further support the cardiac safety of THP in patients with metastatic HER2-positive breast cancer. IMPLICATIONS FOR PRACTICE: Dual anti-HER2 therapy with trastuzumab and pertuzumab in combination with taxane-based chemotherapy improves overall survival in patients with metastatic HER2-positive breast cancer. There is a critical need to investigate the potential cardiotoxicity of dual anti-HER2 blockade, given the importance of HER2 signaling in cardiac homeostasis and stress response. Global longitudinal strain and cardiac biomarkers have been proposed as adjuncts to left ventricular ejection fraction for the early detection of cardiotoxicity. In this phase II study of combination trastuzumab and pertuzumab with paclitaxel, no clinically significant change was observed in global longitudinal strain or cardiac biomarkers. These results further support the cardiac safety of dual anti-HER2 blockade previously reported in the CLEOPATRA study. The findings in the current study also call into question the role of intensive cardiac monitoring among patients treated with anti-HER2 therapy in the absence of anthracyclines. Less frequent cardiac assessments could lead to a reduction in unnecessary treatment interruption and is an important consideration given the rise in medical expenditures, but this requires further investigation.

Risk of Vascular Toxicity with Platinum Based Chemotherapy in Elderly Patients with Bladder Cancer.

PURPOSE: Platinum based chemotherapy is widely used for bladder cancer but is associated with vascular toxicity, especially thromboembolism. We evaluated the short-term (less than 1 year) and intermediate-term (2 to 5 years) vascular toxicity of platinum agents in older patients with bladder cancer. MATERIALS AND METHODS: We identified Medicare beneficiaries 66 to 94 years old diagnosed with stage II-III bladder cancer from 1998 to 2007 in the SEER-Medicare database. We measured the association between platinum based chemotherapy and vascular events (thromboembolic and nonthromboembolic) using Cox proportional hazard regression models. RESULTS: The sample included 5,057 patients, of whom 21.3% received platinum based chemotherapy. Patients receiving platinum based chemotherapy were more likely to be younger and male with less comorbidity than those not receiving any chemotherapy. During the first year after diagnosis the patients who received platinum based chemotherapy had a higher risk of a thromboembolic event (19.8% vs 11.6%, AHR 1.43, 95% CI 1.17-1.75) compared to those who did not receive chemotherapy. The likelihood of having a thromboembolic outcome was similar whether platinum chemotherapy was cisplatin based (21.1%, AHR 1.56, 95% CI 1.22-2.00) or carboplatin based (18.9%, AHR 1.35, 95% CI 1.07-1.71). During years 2 to 5 after diagnosis there was no significant association between platinum chemotherapy and the risk of thromboembolic events. The risk of nonthromboembolic vascular events was not increased with platinum chemotherapy in either period. CONCLUSIONS: Patients receiving platinum based chemotherapy were at higher risk for thromboembolism but not other vascular events, particularly in the first year after diagnosis. This risk of thromboembolism is similar for cisplatin and carboplatin.

Continuous Trastuzumab Therapy in Breast Cancer Patients With Asymptomatic Left Ventricular Dysfunction.

BACKGROUND: Adjuvant trastuzumab is a highly effective targeted treatment that improves survival for patients with HER2-positive breast cancer. However, trastuzumab interruption is recommended for patients who develop treatment-induced cardiotoxicity (i.e., decline in left ventricular ejection fraction [LVEF], with or without symptoms) and can lead to an incomplete course of treatment. We studied the cardiac safety of continuous trastuzumab therapy among patients with asymptomatic declines in LVEF. METHODS: We retrospectively evaluated patients with HER2-positive breast cancer treated with adjuvant trastuzumab at our institution between 2005 and 2010. Treatment-induced cardiotoxicity was defined by an absolute decrease in LVEF of ≥10% to below 55% or an absolute decrease of ≥16%. Logistic regression was used to determine the association between candidate risk factors and treatment-induced cardiotoxicity. RESULTS: Among 573 patients, 92 (16%) developed treatment-induced cardiotoxicity. Trastuzumab was continued without interruption in 31 of 92 patients with treatment-induced cardiotoxicity­all were asymptomatic with LVEF of ≥50% at cardiotoxicity diagnosis with median LVEF of 53% (range, 50%-63%), and none developed heart failure during follow-up. Risk factors associated with treatment-induced cardiotoxicity included age (p = .011), anthracycline chemotherapy (p = .002), and lower pretrastuzumab LVEF (p < .001). CONCLUSION: Among patients who develop asymptomatic treatment-induced cardiotoxicity with LVEF of ≥50%, continuous trastuzumab therapy appears to be safe.

Trastuzumab interruption and treatment-induced cardiotoxicity in early HER2-positive breast cancer.

Trastuzumab improves outcomes among patients with HER2-positive breast cancer but is associated with a risk of treatment-induced cardiotoxicity (TIC). It is unclear how frequently TIC leads to trastuzumab interruption outside of prospective trials, and how TIC is managed in clinical practice. Patients with HER2-postive breast cancer receiving adjuvant trastuzumab from 2005 to 2010 were identified (n = 608). We evaluated the incidence, risk factors, and management of trastuzumab interruption due to TIC. In total, 488 (80 %) patients were treated with anthracycline prior to trastuzumab. Trastuzumab was interrupted in 108 (18 %) patients. Cumulative trastuzumab dose was lower in the interrupted group (median 86 vs. 108 mg/kg, p < 0.0001). The most common reason for interruption was TIC (66 of 108 patients): 20 had symptomatic heart failure and 46 had asymptomatic left ventricular ejection fraction (LVEF) decline. Patients with trastuzumab interruption for TIC were older (54 vs. 50 years, p = 0.014) with lower LVEF before anthracycline (63 vs. 67 %, p < 0.0001) and trastuzumab (62 vs. 67 %, p < 0.0001) therapy. Mean LVEF at baseline, TIC diagnosis, and follow-up after trastuzumab interruption was 63, 45, and 55 %, respectively. Thirty-three of 66 patients with TIC were re-challenged with trastuzumab, and five patients had recurrent LVEF decline. In clinical practice, trastuzumab interruption is common and most often due to TIC, with most patients receiving anthracycline prior to trastuzumab. Cardiac dysfunction improves after trastuzumab interruption but may not fully recover to baseline. Strategies to minimize cardiotoxicity and treatment interruption should be investigated to prevent persistent left ventricular dysfunction in affected patients.

Cardiovascular events, early discontinuation of trastuzumab, and their impact on survival.

To evaluate how often trastuzumab therapy is ended early (i.e., early discontinuation) and how cardiovascular events and early discontinuation affect survival among older women with breast cancer. A population-based cohort of female Medicare beneficiaries with stage I-III breast cancer in 2005-2009 who received trastuzumab was assembled and followed through 2011. Completed trastuzumab treatment was defined as ≥11 months of continuous trastuzumab treatments with no delay between trastuzumab treatments >45 days. We identified trastuzumab-associated cardiovascular events as those occurring within 45 days before or after the last trastuzumab treatment. Using Cox proportional hazard models, we examined the association between early discontinuation of trastuzumab and cardiovascular events on all-cause mortality. Our cohort consisted of 585 women (mean age: 71.6 years). Approximately 41 % of women discontinued trastuzumab therapy early. Patients with early discontinuation of trastuzumab were more likely to have heart failure /cardiomyopathy, atrial fibrillation, and other cardiovascular events than women who completed trastuzumab. Cardiovascular events were strongly associated with an increased risk of all-cause mortality [adjusted hazard ratio (AHR) 3.54; 95 % confidence interval (CI) 1.87 to 6.68]. Women with early discontinuation of trastuzumab had a non-significant increase in risk of all-cause mortality (AHR: 1.74; 95 % CI 0.94 to 3.23), compared to women who completed trastuzumab. Early trastuzumab discontinuation was common among older patients, and often associated with adverse cardiovascular events. Development of cardiovascular events was associated with a higher mortality risk than early trastuzumab discontinuation, implying that reducing cardiovascular complications from trastuzumab therapy could likely have a substantive impact on overall survival in this population.

Cardiomyopathy associated with cancer therapy.

Chemotherapy-associated cardiomyopathy is a well known cardiotoxicity of contemporary cancer treatment and a cause of increasing concern for both cardiologists and oncologists. As cancer outcomes improve, cardiovascular disease has become a leading cause of morbidity and mortality among cancer survivors. Asymptomatic or symptomatic left ventricular systolic dysfunction in the setting of cardiotoxic chemotherapy is an important entity to recognize. Early diagnosis of cardiac injury through the use of novel blood-based biomarkers or noninvasive imaging modalities may allow for the initiation of cardioprotective medications or modification of chemotherapy regimen to minimize or prevent further damage. Several clinical trials are currently underway to determine the efficacy of cardioprotective medications for the prevention of chemotherapy-associated cardiomyopathy. Implementing a strategy that includes both early detection and prevention of cardiotoxicity will likely have a significant impact on the overall prognosis of cancer survivors. Continued coordination of care between cardiologists and oncologists remains critical to maximizing the oncologic benefit of cancer therapy while minimizing any early or late cardiovascular effects.

Cardiac metastases from head and neck cancer mimicking a myocardial infarction.

Cardiac metastases from head and neck cancer are rare. We present 2 patients with primary head and neck cancer found to have cardiac metastases. Electrocardiograms showed a persistent acute infarction pattern due to myocardial tumor infiltration. No cardiac symptoms were present. Both patients died of metastatic disease.

Echocardiographic Functional Outcomes Following Regional Nodal Irradiation for Breast Cancer Using Volumetric Modulated Arc Therapy.

Purpose: Regional nodal irradiation (RNI) for breast cancer yields improvements in disease outcomes, yet comprehensive target coverage often increases cardiac radiation therapy (RT) dose. Volumetric modulated arc therapy (VMAT) may mitigate high-dose cardiac exposure, although it often increases the volume of low-dose exposure. The cardiac implications of this dosimetric configuration (in contrast to historic 3D conformal techniques) remain uncertain. Methods and Materials: Eligible patients receiving adjuvant RNI using VMAT for locoregional breast cancer were prospectively enrolled in an IRB-approved study. Echocardiograms were performed prior to RT, at the conclusion of RT, and 6 months following RT. Echocardiographic parameters were measured by a single reader and measures were compared pre- and post-RT via the signed-rank test. Changes in echocardiographic parameters over time were compared to mean and max heart doses via the Spearman correlation test. Results: Among 19 evaluable patients (median age 38 years), 89% (n = 17) received doxorubicin and 37% (n = 7) received trastuzumab/pertuzumab combination therapy. All patients received VMAT-based whole-breast/chest wall and RNI. The average mean heart dose was 456 cGy (range, 187-697 cGy) and the average max heart dose was 3001 cGy (1560-4793 cGy). Among salient echocardiographic parameters, no significant decrement in cardiac function was observed when comparing pre-RT to 6 months post-RT: mean left ventricular ejection fraction (LVEF) was 61.8% (SD 4.4%) pre-RT and 62.7% (SD 3.8%) 6 months post-RT (P = .493); mean global longitudinal strain (GLS) was -19.3% (SD 2.2%) pre-RT and -19.6% (SD 1.8%) 6 months post-RT (P = .627). No individual patient exhibited reduced LVEF or sustained decrement in GLS. No correlations were observed for changes in LVEF or GLS when compared to mean or maximum heart doses (P > .1 for all). Conclusions: VMAT for left-sided RNI yielded no significant early decrement in echocardiographic parameters of cardiac function, including LVEF and GLS, within this limited cohort. No patient exhibited significant LVEF changes, and none exhibited sustained decrements in GLS. VMAT may be a reasonable approach to cardiac avoidance in patients requiring RNI, including those receiving anthracyclines and HER2-directed therapy. Larger cohorts with longer follow-ups will be needed to validate these findings.

Incremental Utility of First-Pass Perfusion CMR for Prognostic Risk Stratification of Cancer-Associated Cardiac Masses.

BACKGROUND: Cardiac magnetic resonance (CMR) differentiates cardiac metastasis (CMET) and cardiac thrombus (CTHR) based on tissue characteristics stemming from vascularity on late gadolinium enhancement (LGE). Perfusion CMR can assess magnitude of vascularity; utility for cardiac masses (CMASS) is unknown. OBJECTIVES: This study sought to determine if perfusion CMR provides diagnostic and prognostic utility for CMASS beyond binary differentiation of CMET and CTHR. METHODS: The population comprised adult cancer patients with CMASS on CMR; CMET and CTHR were defined using LGE-CMR: CMASS+ patients were matched to CMASS- control subjects for cancer type/stage. First-pass perfusion CMR was interpreted visually and semiquantitatively for CMASS vascularity, including contrast enhancement ratio (CER) (plateau vs baseline) and contrast uptake rate (CUR) (slope). Follow-up was performed for all-cause mortality. RESULTS: A total of 462 cancer patients were studied, including patients with (CMET = 173, CTHR = 69) and without CMASS on LGE-CMR. On perfusion CMR, CER and CUR were higher within CMET vs CTHR (P < 0.001); CUR yielded better performance (AUC: 0.89-0.93) than CER (AUC: 0.66-0.72) (both P < 0.001) to differentiate LGE-CMR-evidenced CMET and CTHR, although both CUR (P = 0.10) and CER (P = 0.01) typically misclassified CMET with minimal enhancement. During follow-up, mortality among CMET patients was high but variable; 47% of patients were alive 1 year post-CMR. Patients with semiquantitative perfusion CMR-evidenced CMET had higher mortality than control subjects (HR: 1.42 [95% CI: 1.06-1.90]; P = 0.02), paralleling visual perfusion CMR (HR: 1.47 [95% CI: 1.12-1.94]; P = 0.006) and LGE-CMR (HR: 1.52 [95% CI: 1.16-2.00]; P = 0.003). Among patients with CMET on LGE-CMR, mortality was highest among patients (P = 0.002) with lesions in the bottom perfusion (CER) tertile, corresponding to low vascularity. Among CMET and cancer-matched control subjects, mortality was equivalent (P = NS) among patients with lesions in the upper CER tertile (corresponding to higher lesion vascularity). Conversely, patients with CMET in the middle (P = 0.03) and lowest (lowest vascularity) (P = 0.001) CER tertiles had increased mortality. CONCLUSIONS: Perfusion CMR yields prognostic utility that complements LGE-CMR: Among cancer patients with LGE-CMR defined CMET, mortality increases in proportion to magnitude of lesion hypoperfusion.

Rationale and design of a cardiac safety study for reduced cardiotoxicity surveillance during HER2-targeted therapy.

BACKGROUND: Echocardiograms are recommended every 3 months in patients receiving human epidermal growth factor 2 (HER2)-targeted therapy for surveillance of left ventricular ejection fraction (LVEF). Efforts to tailor treatment for HER2-positive breast cancer have led to greater use of non-anthracycline regimens that are associated with lower cardiotoxicity risk, raising into question the need for frequent cardiotoxicity surveillance for these patients. This study seeks to evaluate whether less frequent cardiotoxicity surveillance (every 6 months) is safe for patients receiving a non-anthracycline HER2-targeted treatment regimen. METHODS/DESIGN: We will enroll 190 women with histologically confirmed HER2-positive breast cancer scheduled to receive a non-anthracycline HER2-targeted treatment regimen for a minimum of 12 months. All participants will undergo echocardiograms before and 6-, 12-, and 18-months after initiation of HER2-targeted treatment. The primary composite outcome is symptomatic heart failure (New York Heart Association class III or IV) or death from cardiovascular causes. Secondary outcomes include: 1) echocardiographic indices of left ventricular systolic function; 2) incidence of cardiotoxicity, defined by a ≥ 10% absolute reduction in left ventricular ejection fraction (LVEF) from baseline to < 53%; and 3) incidence of early interruption of HER2-targeted therapy. CONCLUSIONS: To our knowledge, this will be the first prospective study of a risk-based approach to cardiotoxicity surveillance. We expect findings from this study will inform the development of updated clinical practice guidelines to improve cardiotoxicity surveillance practices during HER2-positive breast cancer treatment. TRIAL REGISTRATION: The trial was registered in the ClinicalTrials.gov registry (identifier NCT03983382) on June 12, 2019.

Nomogram for Predicting Risk of Cancer Therapy-Related Cardiac Dysfunction in Patients With Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer.

BACKGROUND: Cancer therapy-related cardiac dysfunction (CTRCD) is an important treatment-limiting toxicity for patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer that adversely affects cancer and cardiovascular outcomes. Easy-to-use tools that incorporate readily accessible clinical variables for individual estimation of CTRCD risk are needed. METHODS AND RESULTS: From 2004 to 2013, 1440 patients with stage I to III HER2-positive breast cancer treated with trastuzumab-based therapy were identified. A multivariable Cox proportional hazards model was constructed to identify risk factors for CTRCD and included the 1377 patients in whom data were complete. Nine clinical variables, including age, race, body mass index, left ventricular ejection fraction, systolic blood pressure, coronary artery disease, diabetes, arrhythmia, and anthracycline exposure were built into a nomogram estimating risk of CTRCD at 1 year. The nomogram was validated for calibration and discrimination using bootstrap resampling. A total of 177 CTRCD events occurred within 1 year of HER2-targeted treatment. The nomogram for prediction of 1-year CTRCD probability demonstrated good discrimination, with a concordance index of 0.687. The predicted and observed probabilities of CTRCD were similar, demonstrating good model calibration. CONCLUSIONS: A nomogram composed of 9 readily accessible clinical variables provides an individualized 1-year risk estimate of CTRCD among women with HER2-positive breast cancer receiving HER2-targeted therapy. This nomogram represents a simple-to-use tool for clinicians and patients that can inform clinical decision-making on breast cancer treatment options, optimal frequency of cardiac surveillance, and role of cardioprotective strategies.

Association of Circulating Cardiomyocyte Cell-Free DNA With Cancer Therapy-Related Cardiac Dysfunction in Patients Undergoing Treatment for ERBB2-Positive Breast Cancer.

Importance: Cancer therapy-related cardiac dysfunction (CTRCD) is a potentially serious cardiotoxicity of treatments for ERBB2-positive breast cancer (formerly HER2). Identifying early biomarkers of cardiotoxicity could facilitate an individualized approach to cardiac surveillance and early pharmacologic intervention. Circulating cell-free DNA (cfDNA) of cardiomyocyte origin is present during acute cardiac injury but has not been established as a biomarker of CTRCD. Objective: To determine whether circulating cardiomyocyte cfDNA is associated with CTRCD in patients with ERBB2-positive breast cancer treated with anthracyclines and ERBB2-targeted therapy. Design, Setting, and Participants: A prospective cohort of 80 patients with ERBB2-positive breast cancer enrolled at an academic cancer center between July 2014 and April 2016 underwent echocardiography and blood collection at baseline, after receiving anthracyclines, and at 3 months and 6 months of ERBB2-targeted therapy. Participants were treated with doxorubicin-based chemotherapy followed by trastuzumab (+/- pertuzumab). The current biomarker study includes participants with sufficient biospecimen available for analysis after anthracycline therapy. Circulating cardiomyocyte-specific cfDNA was quantified by a methylation-specific droplet digital polymerase chain reaction assay. Data for this biomarker study were collected and analyzed from June 2021 through April 2022. Main Outcomes and Measures: The outcome of interest was 1-year CTRCD, defined by symptomatic heart failure or an asymptomatic decline in left ventricular ejection fraction (≥10% from baseline to less than lower limit of normal or ≥16%). Values for cardiomyocyte cfDNA and high-sensitivity cardiac troponin I (hs-cTnI) measured after patients completed treatment with anthracyclines were compared between patients who later developed CTRCD vs patients who did not using the Wilcoxon rank sum test, and the association of post-anthracycline cardiomyocyte cfDNA level with CTRCD was estimated using logistic regression. Results: Of 71 patients included in this study, median (IQR) age was 50 (44-58) years, all were treated with dose-dense doxorubicin, and 48 patients underwent breast radiotherapy. Ten of 71 patients (14%) in this analysis developed CTRCD. The level of cardiomyocyte cfDNA at the post-anthracycline time point was higher in patients who subsequently developed CTRCD (median, 30.5 copies/mL; IQR, 24-46) than those who did not (median, 7 copies/mL; IQR, 2-22; P = .004). Higher cardiomyocyte cfDNA level after completion of anthracycline chemotherapy was associated with risk of CTRCD (hazard ratio, 1.02 per 1-copy/mL increase; 95% CI, 1.00-1.03; P = .046). Conclusions and Relevance: This study found that higher cardiomyocyte cfDNA level after completion of anthracycline chemotherapy was associated with risk of CTRCD. Cardiomyocyte cfDNA quantification shows promise as a predictive biomarker to refine risk stratification for CTRCD among patients with breast cancer receiving cardiotoxic cancer therapy, and its use warrants further validation. Trial Registration: ClinicalTrials.gov Identifier: NCT02177175.