Overview and management of cardiac adverse events associated with tyrosine kinase inhibitors

Cardiotoxicity of Anticancer Drugs: Molecular Mechanisms, Clinical Management and Innovative Treatment

With the continuous refinement of therapeutic measures, the survival rate of tumor patients has been improving year by year, while cardiovascular complications related to cancer therapy have become increasingly prominent. Exploring the mechanism and prevention strategy of cancer therapy-related cardiovascular toxicity (CTR-CVT) remains one of the research hotspots in the field of Cardio-Oncology in recent years. Cardiotoxicity of anticancer drugs involves heart failure, myocarditis, hypertension, arrhythmias and vascular toxicity, mechanistically related to vascular endothelial dysfunction, ferroptosis, mitochondrial dysfunction and oxidative stress. To address the cardiotoxicity induced by different anticancer drugs, various therapeutic measures have been put in place, such as reducing the accumulation of anticancer drugs, shifting to drugs with less cardiotoxicity, using cardioprotective drugs, and early detection. Due to the very limited treatments available to ameliorate anticancer drugs-induced cardiotoxicity, a few innovations are being shifted from animal studies to human studies. Examples include mitochondrial transplantation. Mitochondrial transplantation has been proven to be effective in in vivo and in vitro experiments. Several recent studies have demonstrated that intercellular mitochondrial transfer can ameliorate doxorubicin(DOX)-induced cardiotoxicity, laying the foundation for innovative therapies in anticancer drugs-induced cardiotoxicity. In this review, we will discuss the current status of anticancer drugs-induced cardiotoxicity in terms of the pathogenesis and treatment, with a focus on mitochondrial transplantation, and we hope that this review will bring some inspiration to you.

Pharmacotherapy and cardiovascular challenges: a case report of olverembatinib-induced myocardial infarction with non-obstructive coronary arteries

The anticancer drug of tyrosine kinase-inhibitors (TKIs) has significantly improved the prognosis of patients with specific leukemia but has also increased the risk of organ adverse reactions. Herein, we present a case of a patient diagnosed with myeloproliferative neoplasms who experienced recurrent chest pain after receiving treatment with Olverembatinib. Electrocardiography and coronary angiography confirmed the diagnosis of myocardial infarction with non-obstructive coronary arteries. This case serves as a reminder for clinicians to pay more attention and actively prevent the cardiac adverse reactions of TKIs when using such medications.

New-onset keratitis associated with epidermal growth factor receptor-based targeted therapies in Han Chinese patients with lung cancer: A multi-center cohort study

PURPOSE

To determine the risk and incidence of keratitis following treatment with epidermal growth factor receptor inhibitors (EGFRi) and subtypes of EGFRi-associated keratitis.

METHODS

This multi-center cohort study included EGFRi-treated patients and non-users with lung cancer between 2010 and 2023. EGFRi included first-generation agent gefitinib and erlotinib, second-generation agent afatinib, and third-generation agent osimertinib. The primary outcome was new-onset keratitis. Cox proportional hazard models with multivariable adjustment were applied to determine the effect of EGFRi on keratitis over time. Subgroup analyses were conducted, stratified by agents of EGFRi. Sub-outcome analyses were performed to identify the subtypes of EGFRi-associated keratitis.

RESULTS

A total of 1549 EGFRi-treated patients and 6146 non-users were included. 38 (2.5%) EGFRi-treated patients developed keratitis. The incidence of keratitis in EGFRi-treated patients was significantly higher than that in controls (incidence rate, IR, per 1000 person-years = 14.7 vs 4.49, p < 0.0001). EGFRi-treated patients presented with an increased risk for keratitis (adjusted hazard ratio, aHR = 3.14, 95% CI = 1.85-5.35, p < 0.001). Erlotinib (aHR = 2.64, 95% CI = 1.35-5.15, p = 0.004), afatinib (aHR = 4.42, 95% CI = 2.17-9.02, p < 0.001), and osimertinib (aHR = 4.67, 95% CI = 1.60-13.64, p = 0.005), but not gefitinib (aHR = 2.30, 95% CI = 0.96-5.55, p = 0.063), significantly contributed to the risk of keratitis. Subtypes of EGFRi-associated keratitis included corneal ulcer (IR = 2.31 vs 0.166, p < 0.0001) and keratoconjunctivitis (IR = 9.27 vs 2.91, p < 0.0001). None of the EGFRi-treated patients developed perforated corneal ulcer, interstitial and deep keratitis, or corneal neovascularization.

CONCLUSION

Treatment with EGFRi was associated with an increased risk of keratitis. Ocular toxicity of EGFRi was highest for third-generation agents, followed by second-generation agents, and then first-generation agents.

In vitro PK/PD modeling of tyrosine kinase inhibitors in non-small cell lung cancer cell lines

Tyrosine kinase inhibitors (TKIs) are routinely prescribed for the treatment of non-small cell lung cancer (NSCLC). As with all medications, patients can experience adverse events due to TKIs. Unfortunately, the relationship between many TKIs and the occurrence of certain adverse events remains unclear. There are limited in vivo studies which focus on TKIs and their effects on different regulation pathways. Many in vitro studies, however, that investigate the effects of TKIs observe additional changes, such as changes in gene activations or protein expressions. These studies could potentially help to gain greater understanding of the mechanisms for TKI induced adverse events. However, in order to utilize these pathways in a pharmacokinetic/pharmacodynamic (PK/PD) framework, an in vitro PK/PD model needs to be developed, in order to characterize the effects of TKIs in NSCLC cell lines. Through the use of ordinary differential equations, cell viability data and nonlinear mixed effects modeling, an in vitro TKI PK/PD model was developed with estimated PK and PD parameter values for the TKIs alectinib, crizotinib, erlotinib, and gefitinib. The relative standard errors for the population parameters are all less than 25%. The inclusion of random effects enabled the model to predict individual parameter values which provided a closer fit to the observed response. It is hoped that this model can be extended to include in vitro data of certain pathways that may potentially be linked with adverse events and provide a better understanding of TKI-induced adverse events.

Heartbreaker: Detection and prevention of cardiotoxicity in hematological malignancies

Cancer survivors are at significant risk of cardiovascular (CV) morbidity and mortality; patients with hematologic malignancies have a higher rate of death due to heart failure compared to all other cancer subtypes. The majority of conventional hematologic cancer treatments is associated with increased risk of acute and long-term CV toxicity. The incidence of cancer therapy induced CV toxicity depends on the combination of patient characteristics and on the type, dose, and duration of the therapy. Early diagnosis of CV toxicity, appropriate referral, more specific cardiac monitoring follow-up and timely interventions in target patients can decrease the risk of CV adverse events, the interruption of oncological therapy, and improve the patient's prognosis. Herein, we summarize the CV effects of conventional treatments used in hematologic malignancies with a focus on definitions and incidence of the most common CV toxicities, guideline recommended early detection approaches, and preventive strategies before and during cancer treatments.

The efficacy and safety of exercise regimens to mitigate chemotherapy cardiotoxicity: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Cardiotoxicity is one of the most common adverse events of the chemotherapy. Physical exercise was shown to be cardioprotective. We aim to estimate the efficacy and safety of exercise in cancer patients receiving cardiotoxic chemotherapy.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs), which were retrieved by systematically searching PubMed, Web of Science, SCOPUS, Cochrane, Clinical Trials.gov, and MedRxiv through July 17th, 2023. We used RevMan V. 5.4 to pool dichotomous data using risk ratio (RR) and continuous data using mean difference (MD), with a 95% confidence interval (CI).

PROSPERO ID

CRD42023460902.

RESULTS

We included thirteen RCTs with a total of 952 patients. Exercise significantly increased VO2 peak (MD: 1.95 with 95% CI [0.59, 3.32], P = 0.005). However, there was no significant effect regarding left ventricular ejection fraction, global longitudinal strain, cardiac output, stroke volume, left ventricular end-diastolic volume, left ventricular end-systolic volume, E/A ratio, resting heart rate, peak heart rate, resting systolic blood pressure, and resting diastolic blood pressure. Also, there was no significant difference regarding any adverse events (AEs) (RR: 4.44 with 95% CI [0.47, 41.56], P = 0.19), AEs leading to withdrawal (RR: 2.87 with 95% CI [0.79, 10.43], P = 0.11), serious AEs (RR: 3.00 with 95% CI [0.14, 65.90], P = 0.49), or all-cause mortality (RR: 0.25 with 95% CI [0.03, 2.22], P = 0.21).

CONCLUSION

Exercise is associated with increased VO2 peak in cancer patients receiving cardiotoxic chemotherapy. However, there was no significant difference between exercise and usual care regarding the echocardiographic and safety outcomes.

Heart Disease Mortality in Cancer Survivors: A Population-Based Study in Japan

BACKGROUND

Data on the risk of cardiovascular-related mortality in patients with cancer are limited.

METHODS AND RESULTS

This retrospective cohort study used data from the Osaka Cancer Registry and vital statistics in Japan between 1985 and 2013. The causes of death were investigated, and the risk of fatal heart disease was analyzed. Standardized mortality ratios were calculated to compare the risk of fatal heart disease between patients with cancer and the general population. Fine and Gray competing risk regression models were used to assess the risk of fatal heart disease among patients with cancer. In total, 682 886 patients with cancer were included in the analysis, and 335 635 patients died during the study period. Heart disease was the leading cause of noncancer deaths, with 10 686 deaths. Among the patients who died of heart disease, 5017 had ischemic heart disease, 3598 had heart failure, 356 had hypertensive disease, and 1715 had other heart diseases. The standardized mortality ratio for heart disease was 2.80 (95% CI, 2.74-2.85). The standardized mortality ratio for ischemic heart disease, heart failure, and hypertensive disease were 3.26 (95% CI, 3.17-3.35), 2.69 (95% CI, 2.60-2.78), and 5.97 (95% CI, 5.38-6.63), respectively. The risk of fatal heart disease increased over time after cancer diagnosis. Men were more likely to die of heart disease than women (subdistribution hazard ratio, 1.08 [95% CI, 1.02-1.16]). The risk of fatal heart disease among cancer survivors has decreased in recent years.

CONCLUSIONS

Cancer survivors have a higher risk of fatal heart disease than the general population.

A practical guide to managing cardiopulmonary toxicities of tyrosine kinase inhibitors in chronic myeloid leukemia

Tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of chronic myeloid leukemia (CML) but their use was associated with a range of serious cardiopulmonary toxicities including vascular adverse events, QT prolongation, heart failure, pleural effusion, and pulmonary arterial hypertension. Dedicated clinical management guidelines for TKI-induced toxicities are not available. This review aims to discuss TKI-associated cardiopulmonary toxicities and proposes a practical guide for their management.

Adverse reactions after treatment with dasatinib in chronic myeloid leukemia: Characteristics, potential mechanisms, and clinical management strategies

Dasatinib, a second-generation tyrosine kinase inhibitor, is recommended as first-line treatment for patients newly diagnosed with chronic myeloid leukemia (CML) and second-line treatment for those who are resistant or intolerant to therapy with imatinib. Dasatinib is superior to imatinib in terms of clinical response; however, the potential pulmonary toxicities associated with dasatinib, such as pulmonary arterial hypertension and pleural effusion, may limit its clinical use. Appropriate management of dasatinib-related severe events is important for improving the quality of life and prognosis of patients with CML. This review summarizes current knowledge regarding the characteristics, potential mechanisms, and clinical management of adverse reactions occurring after treatment of CML with dasatinib.

In silico mechanisms of arsenic trioxide-induced cardiotoxicity

It has been found that arsenic trioxide (ATO) is effective in treating acute promyelocytic leukemia (APL). However, long QT syndrome was reported in patients receiving therapy using ATO, which even led to sudden cardiac death. The underlying mechanisms of ATO-induced cardiotoxicity have been investigated in some biological experiments, showing that ATO affects human ether-à-go-go-related gene (hERG) channels, coding rapid delayed rectifier potassium current (I _Kr ), as well as L-type calcium (I _CaL ) channels. Nevertheless, the mechanism by which these channel reconstitutions induced the arrhythmia in ventricular tissue remains unsolved. In this study, a mathematical model was developed to simulate the effect of ATO on ventricular electrical excitation at cellular and tissue levels by considering ATO's effects on I _Kr and I _CaL . The ATO-dose-dependent pore block model was incorporated into the I _Kr model, and the enhanced degree of ATO to I _CaL was based on experimental data. Simulation results indicated that ATO extended the action potential duration of three types of ventricular myocytes (VMs), including endocardial cells (ENDO), midmyocardial cells (MCELL), and epicardial cells (EPI), and exacerbated the heterogeneity among them. ATO could also induce alternans in all three kinds of VMs. In a cable model of the intramural ventricular strand, the effects of ATO are reflected in a prolonged QT interval of simulated pseudo-ECG and a wide vulnerable window, thus increasing the possibility of spiral wave formation in ventricular tissue. In addition to showing that ATO prolonged QT, we revealed that the heterogeneity caused by ATO is also an essential hazard factor. Based on this, a pharmacological intervention of ATO toxicity by resveratrol was undertaken. This study provides a further understanding of ATO-induced cardiotoxicity, which may help to improve the treatment for APL patients.

Differentiating pulmonary hypertension associated with protein kinase inhibitors

Protein kinase inhibitors (PKIs) have been implicated in pulmonary vascular toxicities including risk factors for at least three of the five World Health Organization groups of pulmonary hypertension (PH). These toxicities include direct drug-induced pulmonary arterial hypertension, an increase in cardiomyopathies, and an increase in interstitial lung disease. On- and off-target toxicities are common within multitargeted PKIs leading to cardiopulmonary toxicities. This review highlights the incidence, possible mechanisms, and management strategies for each group of possible PKI-induced PH. Future identification and clarification of protein kinase pathways for both mechanisms of toxicity and pathophysiology for PH could lead to improvements in patient care in oncology and pulmonary vascular diseases.

The multifaceted roles of mitochondria at the crossroads of cell life and death in cancer

Mitochondria are the cytoplasmic organelles mostly known as the "electric engine" of the cells; however, they also play pivotal roles in different biological processes, such as cell growth/apoptosis, Ca²⁺ and redox homeostasis, and cell stemness. In cancer cells, mitochondria undergo peculiar functional and structural dynamics involved in the survival/death fate of the cell. Cancer cells use glycolysis to support macromolecular biosynthesis and energy production ("Warburg effect"); however, mitochondrial OXPHOS has been shown to be still active during carcinogenesis and even exacerbated in drug-resistant and stem cancer cells. This metabolic rewiring is associated with mutations in genes encoding mitochondrial metabolic enzymes ("oncometabolites"), alterations of ROS production and redox biology, and a fine-tuned balance between anti-/proapoptotic proteins. In cancer cells, mitochondria also experience dynamic alterations from the structural point of view undergoing coordinated cycles of biogenesis, fusion/fission and mitophagy, and physically communicating with the endoplasmic reticulum (ER), through the Ca²⁺ flux, at the MAM (mitochondria-associated membranes) levels. This review addresses the peculiar mitochondrial metabolic and structural dynamics occurring in cancer cells and their role in coordinating the balance between cell survival and death. The role of mitochondrial dynamics as effective biomarkers of tumor progression and promising targets for anticancer strategies is also discussed.

Management of VEGFR-Targeted TKI for Thyroid Cancer

Recent advances in the development of multitarget tyrosine kinase inhibitors (MTKIs), which mainly target the vascular endothelial growth factor receptor (VEGFR), have improved prognoses and dramatically changed the treatment strategy for advanced thyroid cancer. However, adverse events related to this inhibition can interrupt treatment and sometimes lead to discontinuation. In addition, they can be annoying and potentially jeopardize the subjects' quality of life, even allowing that the clinical outcome of patients with advanced thyroid cancer remains limited. In this review, we summarize the potential mechanisms underlying these adverse events (hypertension, proteinuria and renal impairment, hemorrhage, fistula formation/gastrointestinal perforation, wound healing, cardiovascular toxicities, hematological toxicity, diarrhea, fatigue, and acute cholecystitis), their characteristics, and actual management. Furthermore, we also discuss the importance of related factors, including alternative treatments that target other pathways, the necessity of subject selection for safer administration, and patient education.

The Growing Impact of Cardiovascular Oncology: Epidemiology and Pathophysiology

Progress in the treatment of cancer has significantly improved survival of oncologic patients in recent decades. However, anticancer therapies, particularly some new, more potent and targeted agents, are potentially cardiotoxic. As a consequence, cardiovascular complications, including heart failure, arterial hypertension, coronary artery disease, venous thromboembolism, peripheral vascular disease, arrhythmias, pericardial disease, and pulmonary hypertension, as related to cancer itself or to anticancer treatments, are increasingly observed and may adversely affect prognosis in oncologic patients. Cardiovascular oncology is an emerging field in cardiology and internal medicine, which is rapidly growing, dealing with the prevention, the early detection, and the management of cardiovascular disease, in all stages of anticancer therapy and during the survivorship period, now crucial for reducing cardiovascular morbidity and mortality in cancer patients. In this narrative review, the existing literature regarding the epidemiology of cardiovascular oncology, the mechanisms of cardiovascular complications in cancer, and the pathophysiology of cardiotoxicity related to chemotherapeutic agents, targeted therapies, immunotherapies, and radiotherapy will be analyzed and summarized.

Tyrosine kinase inhibitor-induced hypertension-marker of anti-tumour treatment efficacy or cardiovascular risk factor?

Tyrosine kinase receptor inhibitors (TKIs) are a relatively new class of targeted anti-cancer agents with vascular endothelial growth factor signalling pathway-inhibiting properties. Hypertension is recognized as one of the most common adverse effects of this anti-angiogenic therapy and is the consequence of reduced production of vasodilatory nitric oxide and reduced prostacyclin production as well as increased production of vasoconstrictive endothelin-1. TKI-induced hypertension is dose dependent and it has been suggested as a marker of treatment effectiveness. In this issue, Saito et al. report the incidence of treatment-related hypertension in patients treated with lenvatinib, a newer TKI, for non-resectable hepatocellular carcinoma. The authors demonstrate that a subset of TKI-treated patients develop fluid retention 3 weeks after treatment initiation as a consequence of lower urinary sodium excretion and thus provides insights into the pathogenesis of blood pressure elevation in the second phase. These findings contribute to a better understanding of TKI-associated hypertension and help in choosing the most appropriate antihypertensive agents in this setting. Active control of hypertension may help more patients benefit from longer TKI therapy, possibly resulting in better cancer outcomes.

Rationale and proposal for cardio-oncology services in Italy

: In the last 20 years, a substantial improvement in the efficacy of cancer treatment has induced a progressive increase in cancer survival, with an obvious parallel increase in morbidity and mortality related to the adverse effects of anticancer therapy, in particular, cardiovascular complications. In relation to the peculiar aspects related to cardiac and vascular toxicity, clinical management of patients should be ideally reserved for experts in the field of this novel medical discipline, which has been defined as cardio-oncology. The rationale for this choice corresponds to the aim of identifying patients more prone to developing cardiovascular damage, prevent overt cardiotoxicity and conduct active surveillance of treated patients for early identification of cardiac and vascular involvement during short- and long-term follow-up. Due to the burden of treated cancer patients, the development of dedicated cardio-oncology services has become one of the main goals of contemporary medicine, needed to accomplish the peculiar mission of guiding the patients through the narrow path of cancer survival without the expense of cardiovascular damage. The main purpose of cardio-oncology services is to provide dedicated cardiologic care to cancer patients affected by concomitant (subclinical or overt) cardiovascular diseases, either preexisting the cancer onset or acquired during and after the time course of anticancer therapy. In this article, we describe a possible spoke-hub model of cardio-oncology services, which could be appropriately applied in Italy. Rationale, organization, definition of referral criteria, strategies, interventional programs, long-term surveillance and home assistance of this model are described and discussed.

Management of Adverse Events Associated with Cabozantinib Treatment in Patients with Advanced Hepatocellular Carcinoma

Cabozantinib is an oral multikinase inhibitor whose targets include vascular endothelial growth factor receptors, MET, and the TAM family of kinases (TYRO3, AXL, MER). Cabozantinib is approved for patients with advanced hepatocellular carcinoma who have been previously treated with sorafenib, based on improved overall survival and progression-free survival relative to placebo in the phase III CELESTIAL study. During CELESTIAL, the most common adverse events (AEs) experienced by patients receiving cabozantinib included palmar-plantar erythrodysesthesia, fatigue, gastrointestinal-related events, and hypertension. These AEs can significantly impact treatment tolerability and patient quality of life. However, AEs can be effectively managed with supportive care and dose modifications. During CELESTIAL, more than half of the patients receiving cabozantinib required a dose reduction, while the rate of treatment discontinuation due to AEs was low. Here, we review the safety profile of cabozantinib and provide guidance on the prevention and management of the more common AEs, based on current evidence from the literature as well as our clinical experience. We consider the specific challenges faced by clinicians in treating this patient population and discuss factors that may affect exposure and tolerability to cabozantinib.

The effect of partial nephrectomy on blood pressure in patients with solitary kidney

PURPOSE

To determine the effect of partial nephrectomy (PN) in the solitary kidney on systolic and diastolic blood pressures (SBP and DBP, respectively), and use of antihypertensive medications.

METHODS

We performed a retrospective cohort study of solitary kidney patients who underwent PN for kidney cancer from 1999-2015. Primary outcomes evaluated were blood pressure (BP) and antihypertensive medication changes from baseline up to 5 years postoperatively. Using a multivariable mixed-effects model to account for repeated measurements, we evaluated the effect of PN on the outcome measurements while controlling for baseline patient, pathologic, and perioperative characteristics.

RESULTS

292 patients who underwent PN on solitary kidneys met inclusion criteria (median [range] age, 63 [24-84] years; 179 men [61%]). SBP decreased immediately postoperatively (- 1.7 mmHg [- 2.6, - 0.7], p < 0.001), and further decreased by 0.04 mmHg per year (p = 0.01) postoperatively, for a total change of - 1.9 [- 3.9, 0.2] mmHg at 5 years (p = 0.01). DBP decreased immediately postoperatively (- 2.2 mmHg [- 2.7, - 1.7], p < 0.001), and then rebounded by 0.37 mmHg per year (p = 0.003) postoperatively, for a total change of - 0.4 [- 1.5, 0.7] mmHg at 5 years (p = 0.003). Antihypertensive medication use increased at 5 years (0.35 more medications per patient, p < 0.001).

CONCLUSIONS

Our results suggest a minimal change in BP after PN, although patients increased antihypertensive medication use. This data suggests damage to renal parenchyma or hilar nerves during PN did not significantly impact BP regulation in our cohort.

QT interval prolongation related to afatinib treatment in a patient with metastatic non-small-cell lung cancer

Afatinib improves survival in metastatic non-small-cell lung cancer driven by activating epidermal growth factor receptor mutations. QT interval prolongation is a possible side effect of targeted anticancer drugs, but this has not been reported before with afatinib. We report a case of metastatic pulmonary adenocarcinoma with epidermal growth factor receptor exon 19 deletion who was treated with first-line afatinib. The patient was started on afatinib with a total dose of 40 mg/day and experienced grade 3 (>500 ms) QT interval prolongation in the seventh week. Dose was interrupted and then reduced to 30 mg/day after the event repeated. QT prolongation occurred only once with the reduced dose and radiologic oligoprogression was detected. Local therapy was performed and afatinib was continued as 30 mg/day. To the best of our knowledge, this case marks the first QT interval prolongation associated with afatinib. It is prudent to perform a baseline cardiologic evaluation and electrocardiogram monitoring in non-small cell lung cancer patients treated with this drug.

Integrated molecular signaling involving mitochondrial dysfunction and alteration of cell metabolism induced by tyrosine kinase inhibitors in cancer

Cancer cells have unlimited replicative potential, insensitivity to growth-inhibitory signals, evasion of apoptosis, cellular stress, and sustained angiogenesis, invasiveness and metastatic potential. Cancer cells adequately adapt cell metabolism and integrate several intracellular and redox signaling to promote cell survival in an inflammatory and hypoxic microenvironment in order to maintain/expand tumor phenotype. The administration of tyrosine kinase inhibitor (TKI) constitutes the recommended therapeutic strategy in different malignancies at advanced stages.

There are important interrelationships between cell stress, redox status, mitochondrial function, metabolism and cellular signaling pathways leading to cell survival/death. The induction of apoptosis and cell cycle arrest widely related to the antitumoral properties of TKIs result from tightly controlled events involving different cellular compartments and signaling pathways. The aim of the present review is to update the most relevant studies dealing with the impact of TKI treatment on cell function. The induction of endoplasmic reticulum (ER) stress and Ca²⁺ disturbances, leading to alteration of mitochondrial function, redox status and phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt)-mammalian target of rapamycin (mTOR) and AMP-activated protein kinase (AMPK) signaling pathways that involve cell metabolism reprogramming in cancer cells will be covered. Emphasis will be given to studies that identify key components of the integrated molecular pattern including receptor tyrosine kinase (RTK) downstream signaling, cell death and mitochondria-related events that appear to be involved in the resistance of cancer cells to TKI treatments.

Electrophysiologic Complications in Cancer Patients

In recent years, dramatic advances in both cancer diagnosis and treatment have led to significantly increased survival rates. As such, cardiovascular toxicities due to oncologic treatments are more frequently identified. Although heart failure and cardiomyopathy have historically been the cardiotoxicities most associated with cancer therapeutics, it is now recognized that all components of the cardiovascular system can be affected. In this review, we discuss electrophysiologic complications of cancer treatments, including atrial and ventricular tachyarrhythmias as well as bradyarrhythmias, and recommend a multidisciplinary approach with both cardiologists and oncologists to provide safe and effective care to these patients.

Brazilian cardio-oncology: the 10-year experience of the Instituto do Cancer do Estado de Sao Paulo

Background

In recent years, the field of cardio-oncology has grown worldwide, bringing benefits to cancer patients in terms of survival and quality of life. This study reports the experience of a pioneer cardio-oncology programme at University Cancer Hospital in Brazil over a period of 10 years, describing the clinical profile of patients and the clinical outcomes.

Methods

A retrospective study was conducted on a cohort of patients treated at the cardio-oncology programme from April 2009 to February 2019. We analysed the characteristics of patients and outcomes, including mortality, according to the type of clinical indication for outpatient care (general cardiology, perioperative evaluation and follow-up and treatment cardiotoxicity).

Results

From a total of 26,435 medical consultations, we obtained the data of 4535 individuals among the medical care outpatients. When we analysed the clinical characteristics of patients considering the clinical indication - general cardiology, perioperative evaluation and cardiotoxicity outpatient clinics, differences were observed with respect to age (59 [48–66], 66 [58–74] and 69 [62–76], p < 0.001), diabetes (67 [15%], 635 [22.6%] and 379 [29.8%]; p < 0.001), hypertension (196 [43.8%], 1649 [58.7%] and 890 [70.1%], p < 0.001) and dyslipidaemia (87 [19.7%), 735 [26.2%] and 459 [36.2%], p < 0.001). A similar overall mortality rate was observed in the groups (47.5% vs. 45.7% vs. 44.9% [p = 0.650]).

Conclusion

The number of oncologic patients in the Cardio-Oncology Programme has grown in the last decade. A well-structured cardio-oncology programme is the key to achieving the true essence of this area, namely, ongoing care for cancer patients throughout the disease treatment process, optimizing their cardiovascular status to ensure they can receive the best therapy against cancer.

Hospitalized cancer patients with acquired long QT syndrome-a matched case-control study

Background

Our recent study has revealed that many hospitalized patients with acquired long QT syndrome (ALQTS) are cancer patients. This study aims to determine the risk factors and outcomes of hospitalized cancer patients with ALQTS.

Methods

We performed a matched case-control study within a cohort of 10,180 cancer patients hospitalized between September 2013 and April 2016. Among them, 150 patients defined as having severe ALQTS with a markedly prolonged QT interval (QTc ≥ 500 ms) were compared with 293 age-, sex- and cancer-type-matched controls (non-ALQTS). Death as the endpoint was followed for up to 2 years. Cox regression and Kaplan-Meier survival analyses were performed to assess the effects of particular clinical variables on all-cause mortality. Multivariate logistic regression was performed to calculate odds ratios (OR) for various predictors of QT prolongation.

Results

The mortality was significantly higher in ALQTS group (63.3% vs. 33.4%). Hypertension, hypokalemia, hypocalcemia, QT-prolonging drugs, infection, anemia, anti-microtubule agents were contributing factors to ALQTS. Renal insufficiency, male gender and hypokalemia were found to be independent risk factors for all-cause mortality in ALQTS group.

Conclusion

Markedly prolonged QT interval was seen in 1.5% of hospitalized cancer patients. The all-cause mortality was high in cancer patients with severe ALQTS.

Kinases as potential targets for treatment of pulmonary hypertension and right ventricular dysfunction

Pulmonary hypertension (PH) is a progressive pulmonary vasculopathy that causes chronic right ventricular pressure overload and often leads to right ventricular failure. Various kinase inhibitors have been studied in the setting of PH and either improved or worsened the disease, highlighting the importance of understanding the specific role of the respective kinases in a spatiotemporal cellular context. In this review, we will summarize the knowledge on the role of kinases in PH and focus on druggable targets for which certain criteria are met: (a) deregulation of the kinase in PH; (b) small-molecule inhibitors are available (e.g. from the oncology field); (c) preclinical studies have shown their efficacy in PH models; and (d) when available, therapeutic exploitation in human PH has been initiated. Along this line, clinical considerations such as personalized medicine approaches to predict therapy response and adverse side events such as cardiotoxicity together with their clinical management are discussed. LINKED ARTICLES: This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.1/issuetoc.

Management of cardiac disease in cancer patients throughout oncological treatment: ESMO consensus recommendations

Cancer and cardiovascular (CV) disease are the most prevalent diseases in the developed world. Evidence increasingly shows that these conditions are interlinked through common risk factors, coincident in an ageing population, and are connected biologically through some deleterious effects of anticancer treatment on CV health. Anticancer therapies can cause a wide spectrum of short- and long-term cardiotoxic effects. An explosion of novel cancer therapies has revolutionised this field and dramatically altered cancer prognosis. Nevertheless, these new therapies have introduced unexpected CV complications beyond heart failure. Common CV toxicities related to cancer therapy are defined, along with suggested strategies for prevention, detection and treatment. This ESMO consensus article proposes to define CV toxicities related to cancer or its therapies and provide guidance regarding prevention, screening, monitoring and treatment of CV toxicity. The majority of anticancer therapies are associated with some CV toxicity, ranging from asymptomatic and transient to more clinically significant and long-lasting cardiac events. It is critical however, that concerns about potential CV damage resulting from anticancer therapies should be weighed against the potential benefits of cancer therapy, including benefits in overall survival. CV disease in patients with cancer is complex and treatment needs to be individualised. The scope of cardio-oncology is wide and includes prevention, detection, monitoring and treatment of CV toxicity related to cancer therapy, and also ensuring the safe development of future novel cancer treatments that minimise the impact on CV health. It is anticipated that the management strategies discussed herein will be suitable for the majority of patients. Nonetheless, the clinical judgment of physicians remains extremely important; hence, when using these best clinical practices to inform treatment options and decisions, practitioners should also consider the individual circumstances of their patients on a case-by-case basis.

Complications and Toxicities Associated with Cancer Therapies in the Intensive Care Unit

Advances in the management of hematologic malignancies and solid tumors have given rise to diverse modalities to treat cancer other than cytotoxic chemotherapy, including targeted therapies, immunotherapies, and cellular therapies. Currently, there are over 175 FDA-approved antineoplastic agents in the United States, many with a diverse and profound toxicity profile. Complications of antineoplastic therapy may result in the need for intensive care unit (ICU) admission to provide acute symptom management. Accordingly, ICU providers caring for cancer patients should have a working knowledge of the toxicities and complications associated with antineoplastic therapy.

Evaluating vandetanib in the treatment of medullary thyroid cancer: patient-reported outcomes

Medullary thyroid cancers (MTCs) are neuroendocrine tumors, which secrete calcitonin and carcinoembryonic antigen, both of which can serve as tumor markers. Extensive and accurate surgical resection is the primary treatment for MTC, whereas the use of external beam radiotherapy is limited. Moreover, since MTC is derived from thyroid parafollicular cells or C cells, it is not responsive to either radioiodine or thyroid-stimulating hormone suppression, and therefore, they cannot be considered as treatment strategies. Traditional therapies for advanced or metastatic progressive medullary thyroid cancer (pMTC) are poorly effective. Among the new approaches tested in clinical trials, targeted chemotherapies with tyrosine kinase inhibitors (TKIs) are now available and they represent effective interventions for progressive disease, with additional investigational options emerging. This paper reviews the efficacy and safety of vandetanib in patients with a pMTC, as it has been shown to improve progression-free survival (30.5 vs 19.3 months in controls). Vandetanib is approved by the FDA and EMA for symptomatic or progressive MTC in patients with unresectable locally advanced or metastatic disease in adults, adolescents, and children older than 5 years. The most common adverse events in vandetanib-treated patients are diarrhea, rash, folliculitis, nausea, QTc prolongation, hypertension, and fatigue. More data are required to deepen our knowledge on molecular biology of tumor and host defense, with the aim to achieve better prognosis and higher quality of life for affected patients.

Evaluation of the QTc interval during lenvatinib treatment in radioiodine-refractory differentiated thyroid cancer: reports from the real-life clinical practice

As for other tyrosine kinase inhibitors, a prolongation of ECG-recorded QTc intervals may be observed during lenvatinib treatment; a warning on this phenomenon has been stated. However, methods and frequency of ECG recordings have seldom been reported in this context. We present two cases of patients treated with lenvatinib for radioiodine-refractory differentiated thyroid cancer in whom the QTc interval was long monitored through a weekly 12-lead ECG registration. Overall, the maximum QTc increase above baseline was 3 and 31 ms in the first and second patient, respectively. QTc interval did not reach the toxicity value for drug withdrawal in either of the patients. These data may provide further information on cardiac safety profile of lenvatinib in a real-life practice.

From Molecular Mechanisms to Clinical Management of Antineoplastic Drug-Induced Cardiovascular Toxicity: A Translational Overview

Significance: Antineoplastic therapies have significantly improved the prognosis of oncology patients. However, these treatments can bring to a higher incidence of side-effects, including the worrying cardiovascular toxicity (CTX). Recent Advances: Substantial evidence indicates multiple mechanisms of CTX, with redox mechanisms playing a key role. Recent data singled out mitochondria as key targets for antineoplastic drug-induced CTX; understanding the underlying mechanisms is, therefore, crucial for effective cardioprotection, without compromising the efficacy of anti-cancer treatments. Critical Issues: CTX can occur within a few days or many years after treatment. Type I CTX is associated with irreversible cardiac cell injury, and it is typically caused by anthracyclines and traditional chemotherapeutics. Type II CTX is generally caused by novel biologics and more targeted drugs, and it is associated with reversible myocardial dysfunction. Therefore, patients undergoing anti-cancer treatments should be closely monitored, and patients at risk of CTX should be identified before beginning treatment to reduce CTX-related morbidity. Future Directions: Genetic profiling of clinical risk factors and an integrated approach using molecular, imaging, and clinical data may allow the recognition of patients who are at a high risk of developing chemotherapy-related CTX, and it may suggest methodologies to limit damage in a wider range of patients. The involvement of redox mechanisms in cancer biology and anticancer treatments is a very active field of research. Further investigations will be necessary to uncover the hallmarks of cancer from a redox perspective and to develop more efficacious antineoplastic therapies that also spare the cardiovascular system.

Phosphorylation of hepatic farnesoid X receptor by FGF19 signaling-activated Src maintains cholesterol levels and protects from atherosclerosis

The bile acid (BA) nuclear receptor, farnesoid X receptor (FXR/NR1H4), maintains metabolic homeostasis by transcriptional control of numerous genes, including an intestinal hormone, fibroblast growth factor-19 (FGF19; FGF15 in mice). Besides activation by BAs, the gene-regulatory function of FXR is also modulated by hormone or nutrient signaling-induced post-translational modifications. Recently, phosphorylation at Tyr-67 by the FGF15/19 signaling-activated nonreceptor tyrosine kinase Src was shown to be important for FXR function in BA homeostasis. Here, we examined the role of this FXR phosphorylation in cholesterol regulation. In both hepatic FXR-knockout and FXR-knockdown mice, reconstitution of FXR expression up-regulated cholesterol transport genes for its biliary excretion, including scavenger receptor class B member 1 (Scarb1) and ABC subfamily G member 8 (Abcg5/8), decreased hepatic and plasma cholesterol levels, and increased biliary and fecal cholesterol levels. Of note, these sterol-lowering effects were blunted by substitution of Phe for Tyr-67 in FXR. Moreover, consistent with Src's role in phosphorylating FXR, Src knockdown impaired cholesterol regulation in mice. In hypercholesterolemic apolipoprotein E-deficient mice, expression of FXR, but not Y67F-FXR, ameliorated atherosclerosis, whereas Src down-regulation exacerbated it. Feeding or treatment with an FXR agonist induced Abcg5/8 and Scarb1 expression in WT, but not FGF15-knockout, mice. Furthermore, FGF19 treatment increased occupancy of FXR at Abcg5/8 and Scarb1, expression of these genes, and cholesterol efflux from hepatocytes. These FGF19-mediated effects were blunted by the Y67F-FXR substitution or Src down-regulation or inhibition. We conclude that phosphorylation of hepatic FXR by FGF15/19-induced Src maintains cholesterol homeostasis and protects against atherosclerosis.

Cardiotoxicity Monitoring in Patients Treated with Tyrosine Kinase Inhibitors

Tyrosine kinase inhibitors (TKIs) can cause cardiotoxicity, and some suggest routine monitoring of cardiac function during TKI use. We describe two cases of TKI-induced heart failure (HF) that suggest the utility of monitoring with laboratory tests is questionable. One patient developed HF 5 days after starting pazopanib. The other developed HF while receiving 25 mg per day sunitinib, and had previously received a higher dose (50 mg per day) with no symptoms of cardiotoxicy. In addition, she later received 5 cycles of sunitinib (25 mg per day) without developing an abnormal left ventricular ejection fraction (LVEF) value by echocardiography or cardiac symptoms. Although the LVEF is commonly performed to monitor TKI cardiotoxicity, evidence for its predictive utility is limited. These cases raise questions regarding the practical utility of sequential measurement of LVEF in adults treated with TKIs. We suggest a simple daily activity such as stair climbing to monitor exercise tolerance.

Managing the adverse events associated with lenvatinib therapy in radioiodine-refractory differentiated thyroid cancer

Lenvatinib is a multikinase inhibitor of vascular endothelial growth factor (VEGF) receptors 1-3, fibroblast growth factor receptors 1-4, RET, KIT, and platelet-derived growth factor receptor-α. Lenvatinib is approved as a monotherapy for the treatment of radioiodine-refractory differentiated thyroid cancer and in combination with everolimus for the second-line treatment of advanced renal cell carcinoma. Lenvatinib is also under investigation for the treatment of several malignancies including unresectable hepatocellular carcinoma. Although lenvatinib is associated with favorable efficacy, it is associated with adverse events (AEs) that the clinician will have to closely monitor for and proactively manage. Most of these AEs are known class effects of VEGF-targeted therapies, including hypertension, diarrhea, fatigue or asthenia, decreased appetite, and weight loss. This review summarizes the safety profile of lenvatinib and offers guidance for the management of both frequent and rare AEs. We discuss the potential mechanisms underlying these AEs and present practical recommendations for managing toxicities. The development of treatment plans that include prophylactic and therapeutic strategies for the management of lenvatinib-associated AEs has the potential to improve patient quality of life, optimize adherence, minimize the need for dose reductions, treatment interruptions, or discontinuations, and maximize patient outcomes.

Toxicity of cancer therapy: what the cardiologist needs to know about angiogenesis inhibitors

Clinical outcomes for patients with a wide range of malignancies have improved substantially over the last two decades. Tyrosine kinase inhibitors (TKIs) are potent signalling cascade inhibitors and have been responsible for significant advances in cancer therapy. By inhibiting vascular endothelial growth factor receptor (VEGFR)-mediated tumour blood vessel growth, VEGFR-TKIs have become a mainstay of treatment for a number of solid malignancies. However, the incidence of VEGFR-TKI-associated cardiovascular toxicity is substantial and previously under-recognised. Almost all patients have an acute rise in blood pressure, and the majority develop hypertension. They are associated with the development of left ventricular systolic dysfunction (LVSD), heart failure and myocardial ischaemia and can have effects on myocardial repolarisation. Attention should be given to rigorous baseline assessment of patients prior to commencing VEGFR-TKIs, with careful consideration of baseline cardiovascular risk factors. Baseline blood pressure measurement, ECG and cardiac imaging should be performed routinely. Hypertension management currently follows national guidelines, but there may be a future role forendothelin-1 antagonism in the prevention or treatment of VEGFR-TKI-associated hypertension. VEGFR-TKI-associated LVSD appears to be independent of dose and is reversible. Patients who develop LVSD and heart failure should be managed with conventional heart failure therapies, but the role of prophylactic therapy is yet to be defined. Serial monitoring of left ventricular function and QT interval require better standardisation and coordinated care. Management of these complex patients requires collaborative, cardio-oncology care to allow the true therapeutic potential from cancer treatment while minimising competing cardiovascular effects.

The Impact of Pazopanib on the Cardiovascular System

Pazopanib is an approved treatment for renal cell carcinoma and a second-line treatment for nonadipocytic soft-tissue sarcoma. However, its clinical efficacy is limited by its cardiovascular side effects. Pazopanib and other vascular endothelial growth factor receptor tyrosine kinase inhibitors have been associated with the development of hypertension, QT interval prolongation, and other cardiovascular events; however, these mechanisms are largely unknown. Gaining a deeper understanding of these mechanisms is essential for the development of appropriate surveillance strategies and possible diagnostic biomarkers to allow us to monitor patients and modulate therapy prior to significant cardiac insult. This approach will be vital in keeping patients on these life-saving therapies and may be applicable to other tyrosine kinase inhibitors as well. In this review, we provide a comprehensive overview of the preclinical and clinical side effects of pazopanib with a focus on the mechanisms responsible for its toxicity to the cardiovascular system.

Current and emerging therapies for first-line treatment of metastatic clear cell renal cell carcinoma

There has been significant progress in the treatment of patients with advanced clear cell renal cell carcinoma (ccRCC), with improved knowledge of disease biology and the introduction of targeted agents and immunotherapies. In this review, we discuss current and emerging first-line treatment options, including recent approvals of the tyrosine kinase inhibitor (TKI) cabozantinib and the immunotherapy combination of nivolumab (anti-programmed cell death 1 [PD-1])/ipilimumab (anti-cytotoxic T-lymphocyte-associated antigen 4 [CTLA-4]), and initial outcomes with the combination of atezolizumab (anti-PD-ligand 1 [PD-L1])/bevacizumab (anti-vascular endothelial growth factor [VEGF]). Key clinical data are reviewed, as these novel first-line treatments offer significant improvement, particularly for patients classified as intermediate/poor risk for whom previously available therapies have demonstrated limited efficacy. Treatment recommendations based on clinical evidence and expert opinion are discussed. We also review ongoing studies investigating combinations of checkpoint inhibitors with TKIs, including cabozantinib and axitinib, and with other novel immunomodulatory agents, and the potential role of single-agent immunotherapy for select patients. With a growing treatment armamentarium, identification and validation of biomarkers will be crucial for optimizing first-line selection and treatment sequences.

Management of treatment-related toxicities in advanced medullary thyroid cancer

Progress in the treatment of advanced medullary thyroid cancer (MTC) has resulted from the approval of 2 drugs within the past 5 years, vandetanib and cabozantinib. These multikinase inhibitors (MKIs) possess overlapping specificities for multiple kinase targets implicated in the progression of MTC. Both drugs are associated with toxicities, including hypertension, hemorrhage/perforation, diarrhea and other gastrointestinal events, several dermatologic events, and hypothyroidism. In addition, vandetanib is uniquely associated with QTc prolongation through interaction with myocardial potassium channels, and cabozantinib is uniquely associated with hand-foot skin reaction. Treatment-related toxicities occur frequently and can be severe or life-threatening, and patients undergoing long-term treatment will likely experience adverse events (AEs). Here we offer specific practical recommendations for managing AEs commonly occurring with vandetanib and cabozantinib. The recommended approach relies on early recognition and palliation of symptoms, dose interruption, and dose reduction as necessary in order for the patient to maintain the highest tolerable dose for as long as possible and optimal quality of life. Treatment guidelines do not specify a recommended sequence for treating with vandetanib and cabozantinib; however, most patients will receive both drugs during their lifetime. The choice for first-line therapy is individualized after a risk-benefit assessment and depends on physician preference and patient-related factors, such as comorbid conditions. Because most generalist practices may not be familiar with the intricacies of agents such as vandetanib and cabozantinib, we commend that patients with advanced MTC be managed and treated by a thyroid cancer specialist with coordination of care within a multidisciplinary team.

Advances in studies of tyrosine kinase inhibitors and their acquired resistance

Protein tyrosine kinase (PTK) is one of the major signaling enzymes in the process of cell signal transduction, which catalyzes the transfer of ATP-γ-phosphate to the tyrosine residues of the substrate protein, making it phosphorylation, regulating cell growth, differentiation, death and a series of physiological and biochemical processes. Abnormal expression of PTK usually leads to cell proliferation disorders, and is closely related to tumor invasion, metastasis and tumor angiogenesis. At present, a variety of PTKs have been used as targets in the screening of anti-tumor drugs. Tyrosine kinase inhibitors (TKIs) compete with ATP for the ATP binding site of PTK and reduce tyrosine kinase phosphorylation, thereby inhibiting cancer cell proliferation. TKI has made great progress in the treatment of cancer, but the attendant acquired acquired resistance is still inevitable, restricting the treatment of cancer. In this paper, we summarize the role of PTK in cancer, TKI treatment of tumor pathways and TKI acquired resistance mechanisms, which provide some reference for further research on TKI treatment of tumors.

Management of QT prolongation induced by anti-cancer drugs: Target therapy and old agents. Different algorithms for different drugs

The side effects of anticancer drugs still play a critical role in survival and quality of life. Although the recent progresses of cancer therapies have significantly improved the prognosis of oncologic patients, side effects of antineoplastic treatments are still responsible for the increased mortality of cancer survivors. Cardiovascular toxicity is the most dangerous adverse effect induced by anticancer therapies. A survey conducted by the National Health and Nutrition Examination, showed that 1807 cancer survivors followed up for seven years: 51% died of cancer and 33% of heart disease (Vejpongsa and Yeh, 2014). Moreover, the risk of cardiotoxicity persists even with the targeted therapy, the newer type of cancer treatment, due to the presence of on-target and off-target effects related to this new class of drugs. The potential cardiovascular toxicity of anticancer agents includes: QT prolongation, arrhythmias, myocardial ischemia, stroke, hypertension (HTN), thromboembolism, left ventricular dysfunction and heart failure (HF). Compared to other cardiovascular disorders, the interest in QT prolongation and its complications is fairly recent. However, oncologists have to deal with it and to evaluate the risk-benefit ratio before starting the treatment or during the same. Electrolyte abnormalities, low levels of serum potassium and several drugs may favour the acquired QT prolongation. Treatment of marked QT prolongation includes cardiac monitoring, caution in the use or suspension of cancer drugs and correction of electrolyte abnormalities (hypokalaemia, hypomagnesaemia, hypocalcaemia). Syndrome of QT prolongation can be associated with potentially fatal cardiac arrhythmias and its treatment consists of intravenous administration of magnesium sulphate and the use of electrical cardioversion.

Cardiovascular Complications of Cancer Therapy: Best Practices in Diagnosis, Prevention, and Management: Part 2

In this second part of a 2-part review, we will review cancer or cancer therapy-associated systemic and pulmonary hypertension, QT prolongation, arrhythmias, pericardial disease, and radiation-induced cardiotoxicity. This review is based on a MEDLINE search of published data, published clinical guidelines, and best practices in major cancer centers. Newly developed targeted therapy can exert off-target effects causing hypertension, thromboembolism, QT prolongation, and atrial fibrillation. Radiation therapy often accelerates atherosclerosis. Furthermore, radiation can damage the heart valves, the conduction system, and pericardium, which may take years to manifest clinically. Management of pericardial disease in cancer patients also posed clinical challenges. This review highlights the unique opportunity of caring for cancer patients with heart problems caused by cancer or cancer therapy. It is an invitation to action for cardiologists to become familiar with this emerging subspecialty.

Practical management of adverse events associated with cabozantinib treatment in patients with renal-cell carcinoma

Cabozantinib is an oral tyrosine-kinase inhibitor whose targets include VEGFR, MET, and AXL. Cabozantinib is approved for the treatment of patients with advanced clear-cell renal-cell carcinoma (RCC) who have received prior antiangiogenic therapy. In the pivotal Phase III trial of second-line RCC, cabozantinib was associated with a significant improvement in overall survival, progression-free survival, and antitumor response compared with everolimus. Adverse events (AEs) were common for patients receiving cabozantinib, but were effectively managed with supportive care and dose modifications, as discontinuations of cabozantinib due to an AE were infrequent. This article reviews the management of the more common AEs associated with cabozantinib based on findings from the pivotal study, clinical practice guidelines, and the authors' real-world clinical experience, with support from published literature. We focus on hypertension, palmar-plantar erythrodysesthesia, diarrhea, nausea, vomiting, decreased appetite, fatigue, and stomatitis. Effective management of these AEs involves a multimodal strategy that includes patient education, prophylactic and supportive care, and dose modifications. Effective AE management can allow patients to maintain antitumor activity with cabozantinib while mitigating the impact on quality of life.

Targeted Therapy for Medullary Thyroid Cancer: A Review

Medullary thyroid cancers (MTCs) constitute between 2 and 5% of all thyroid cancers. The 10-year overall survival (OS) rate of patients with localized disease is around 95% while that of patients with regional stage disease is about 75%. Only 20% of patients with distant metastases at diagnosis survive 10 years which is significantly lower than for differentiated thyroid cancers. Cases with regional metastases at presentation have high recurrence rates. Adjuvant external radiation confers local control but not improved OS. The management of residual, recurrent, or metastatic disease till a few years ago was re-surgery with local measures such as radiation. Chemotherapy was used with marginal benefit. The development of targeted therapy has brought in a major advantage in management of such patients. Two drugs—vandetanib and cabozantinib—have been approved for use in progressive or metastatic MTC. In addition, several drugs acting on other steps of the molecular pathway are being investigated with promising results. Targeted radionuclide therapy also provides an effective treatment option with good quality of life. This review covers the rationale of targeted therapy for MTC, present treatment options, drugs and methods under investigation, as well as an outline of the adverse effects and their management.