Pembrolizumab-induced myocarditis in a patient with malignant mesothelioma: plasma exchange as a successful emerging therapy-case report

Corticosteroid-resistant immune-related adverse events: a systematic review

Immune checkpoint inhibitor (ICI) treatment has become an important therapeutic option for various cancer types. Although the treatment is effective, ICI can overstimulate the patient's immune system, leading to potentially severe immune-related adverse events (irAEs), including hepatitis, colitis, pneumonitis and myocarditis. The initial mainstay of treatments includes the administration of corticosteroids. There is little evidence how to treat steroid-resistant (sr) irAEs. It is mainly based on small case series or single case reports. This systematic review summarizes available evidence about sr-irAEs. We conducted a systematic literature search in PubMed. Additionally, we included European Society for Medical Oncology, Society for Immunotherapy of Cancer, National Comprehensive Cancer Network and American Society of Clinical Oncology Guidelines for irAEs in our assessment. The study population of all selected publications had to include patients with cancer who developed hepatitis, colitis, pneumonitis or myocarditis during or after an immunotherapy treatment and for whom corticosteroid therapy was not sufficient. Our literature search was not restricted to any specific cancer diagnosis. Case reports were also included. There is limited data regarding life-threatening sr-irAEs of colon/liver/lung/heart and the majority of publications are single case reports. Most publications investigated sr colitis (n=26), followed by hepatitis (n=21), pneumonitis (n=17) and myocarditis (n=15). There is most data for mycophenolate mofetil (MMF) to treat sr hepatitis and for infliximab, followed by vedolizumab, to treat sr colitis. Regarding sr pneumonitis there is most data for MMF and intravenous immunoglobulins (IVIG) while data regarding infliximab are conflicting. In sr myocarditis, most evidence is available for the use of abatacept or anti-thymocyte globulin (ATG) (both with or without MMF) or ruxolitinib with abatacept. This review highlights the need for prompt recognition and treatment of sr hepatitis, colitis, pneumonitis and myocarditis. Guideline recommendations for sr situations are not defined precisely. Based on our search, we recommend-as first line treatment-(1) MMF for sr hepatitis, (2) infliximab for sr colitis, followed by vedolizumab, (3) MMF and IVIG for sr pneumonitis and (4) abatacept or ATG (both with or without MMF) or ruxolitinib with abatacept for sr myocarditis. These additional immunosuppressive agents should be initiated promptly if there is no sufficient response to corticosteroids within 3 days.

Pembrolizumab-induced Myopathy with Anti-striated Muscle Antibodies Successfully Treated by Plasma Exchange

A 70-year-old woman with advanced endometrial cancer developed right ptosis and muscle weakness in the right quadriceps after pembrolizumab administration. Serum creatine kinase (CK) levels were elevated, and anti-striated muscle antibodies were positive. On magnetic resonance imaging, the right vastus lateral muscle showed an abnormal signal. She was diagnosed with pembrolizumab-induced myopathy. We initiated plasma exchange (PE), and the ptosis immediately resolved. We then introduced oral corticosteroids, which improved her muscle weakness. We were able to rapidly diagnose her with ocular symptoms and serum CK level elevation. The early initiation of PE might prevent the exacerbation of pembrolizumab-induced myopathy.

Plasma exchange as a tool for removal of bevacizumab: Highlighting application for urgent surgery

Background

Bevacizumab is commonly used to manage cerebral edema associated with brain tumors. However, its long half-life poses challenges for patients requiring urgent surgery due to wound complications. We present a case of utilizing therapeutic plasma exchange (TPE) to remove bevacizumab in a patient with recurrent glioblastoma requiring urgent surgery.

Methods

A 58-year-old male with recurrent glioblastoma, IDH-wildtype, presented with clinical and radiographic concern for ventriculitis requiring urgent wound washout only 4 days after his last bevacizumab infusion. TPE was performed for 3 sessions after surgery using a centrifugation-based cell separator. Replacement fluids included normal serum albumin, normal saline, and fresh frozen plasma. Bevacizumab levels were quantified using an enzyme-linked immunoabsorbent assay before and after each TPE session.

Results

TPE effectively removed bevacizumab, enabling safe surgery without new complications. Plasma bevacizumab levels decreased from 1087.63 to 145.35 ng/mL (13.4% of original) by the end of the last TPE session. This decline is consistent with nearly 3 half-lives, which compares favorably to the expected timeline of natural decline given the 21-day half-life.

Conclusions

We report a complex clinical scenario of a patient requiring urgent wound washout 4 days after last bevacizumab infusion for CNS infection. Surgery was successfully performed without new complications with use of TPE to remove bevacizumab immediately following surgery. This case highlights the feasibility of this approach, which may be utilized effectively in patients requiring surgery after having recently received bevacizumab.

Immune interactions in pembrolizumab (PD-1 inhibitor) cancer therapy and cardiovascular complications

The use of immunotherapies like pembrolizumab (PEM) is increasingly common for the management of numerous cancer types. The use of PEM to bolster T-cell response against tumor growth is well documented. However, the interactions PEM has on other immune cells to facilitate tumor regression and clearance is unknown and warrants further investigation. In this review, we present literature findings that have reported the interactions of PEM in stimulating innate and adaptive immune cells, which enhance cytotoxic phenotypes. This triggers secretion of cytokines and chemokines, which have both beneficial and detrimental effects. We also describe how this leads to the development of rare but underreported occurrence of PEM-induced immune-related cardiovascular complications that arise suddenly and progress rapidly to debilitating and fatal consequences. This review encourages further research and investigation of PEM-induced cardiovascular complications and other immune cell interactions in patients with cancer. As PEM therapy in treating cancer types is expanding, we expect that this review will inform health care professionals of diverse specializations of medicine like dermatology (melanoma skin cancers), ophthalmology (eye cancers), and pathology (hematological malignancies) about PEM-induced cardiac complications.

Pembrolizumab-Induced Fatal Myasthenia, Myocarditis, and Myositis in a Patient with Metastatic Melanoma: Autopsy, Histological, and Immunohistochemical Findings-A Case Report and Literature Review

Immune checkpoint inhibitors (ICIs) represent a major advance in cancer treatment. The lowered immune tolerance induced by ICIs brought to light a series of immune-related adverse events (irAEs). Pembrolizumab belongs to the ICI class and is a humanized IgG4 anti-PD-1 antibody that blocks the interaction between PD-1 and PD-L1. The ICI-related irAEs involving various organ systems and myocarditis are uncommon (incidence of 0.04% to 1.14%), but they are associated with a high reported mortality. Unlike idiopathic inflammatory myositis, ICI-related myositis has been reported to frequently co-occur with myocarditis. The triad of myasthenia, myositis, and myocarditis must not be underestimated as they can rapidly deteriorate, leading to death. Herein we report a case of a patient with metastatic melanoma who fatally developed myasthenia gravis, myocarditis, and myositis, after a single cycle of pembrolizumab. Considering evidence from the literature review, autopsy, histological, and immunohistochemical investigations on heart and skeletal muscle are presented and discussed, also from a medical-legal perspective.

Electrocardiographic Features of Immune Checkpoint Inhibitor-Associated Myocarditis

Immune checkpoint inhibitors (ICIs) are associated with immune-related adverse events including myocarditis, whilst improving cancer-related outcomes. There is thus a clinical need to identify electrocardiographic manifestations of ICI-related myocarditis to guide clinical management. PubMed was searched for clinical studies and case reports describing electrocardiographic changes in patients with ICI-related myocarditis. A total of 6 clinical studies and 79 case reports were included. This revealed a range of presentations for patients on ICIs, including supraventricular arrhythmias, ventricular arrhythmias and heart block, and new changes of ST-T segment unrelated to coronary artery disease, ST-segment elevation or depression and T-wave abnormalities. Several patients showed low voltages in multiple leads and new onset Q-wave development. Patients with ICI-related myocarditis may develop new arrhythmia and ST-T changes, and infrequently low voltages in multiple leads.

Case report: Electrocardiographic changes in pembrolizumab-induced fatal myocarditis

Immune checkpoint inhibitor (ICI)-induced myocarditis is rare but fatal. Because of the rapid course of ICI-induced myocarditis, understanding of clinical course is only possible through information from case reports. We report a case of pembrolizumab-induced myocarditis in which we were able to document the course of electrocardiographic changes from onset to death. A 58-year-old woman with stage IV lung adenocarcinoma, who had completed her first cycle of pembrolizumab, carboplatin, and pemetrexed, was admitted with pericardial effusion. She underwent pericardiocentesis after admission. A second cycle of chemotherapy was administered 3 weeks after the first cycle. Twenty-two days after admission, she developed a mild sore throat and tested positive for SARS-CoV-2 antigen. She was diagnosed with mild coronavirus disease 2019 (COVID-19), isolated, and treated with sotrovimab. Thirty-two days after admission, an electrocardiogram showed monomorphic ventricular tachycardia (VT). Suspecting myocarditis caused by pembrolizumab, the patient was started on daily methylprednisolone after coronary angiography and endocardial biopsy. Eight days after the start of methylprednisolone administration, she was considered to have passed the acute stage. However, four days later, R-on-T phenomenon triggered polymorphic VT and she died. The impact of viral infections such as COVID-19 on patients be treated with immune checkpoint inhibitors is still unknown and we need to be careful with systemic management after viral infections.

Nivolumab-induced Myositis and Myocarditis with Positive Anti-titin Antibody and Anti-voltage-gated Potassium Channel Kv1.4 Antibody

Immune checkpoint inhibitors (ICIs) are complicated by immune-related adverse events (irAEs), such as myositis, myocarditis, and myasthenia gravis (MG). Anti-titin antibody and anti-voltage-gated potassium channel Kv1.4 antibody are anti-striated antibodies that are frequently detected in MG patients with myositis and/or myocarditis. However, the clinical relationship between positive anti-striated antibodies and irAEs of ICIs remains unknown. We herein report a case of nivolumab-induced myositis and myocarditis with positive anti-titin antibody and anti-voltage-gated potassium channel Kv1.4 antibody in a patient with non-small-cell lung cancer. We also review reported cases of positive anti-striated antibodies related to irAEs of ICIs.

Pembrolizumab-induced Myasthenia Gravis: Literature Review of Ocular Manifestations and a Refractory Case

Immune checkpoint inhibition is a new and promising therapy approved for the treatment of various malignancies. Pembrolizumab is a potent tumor suppressor that acts by upregulating the immune system to recognize cancer cells which may result in disrupted self-tolerance. We describe a case and perform a literature review of myasthenia gravis with ocular manifestations after treatment with pembrolizumab. Our case had bilateral ptosis refractory to conventional treatment, and she remained functionally blind as a result. The literature review included 28 cases of immune-related myasthenia gravis, and a 30% mortality rate excluding deaths from primary cancer progression was shown. Under half had full symptom resolution (n=13, 46%), and there was no clear correlation between specific management strategies and prognosis. Patients with isolated ocular myasthenia gravis (n=9, 32%) were twice as likely to be symptom-free after treatment compared with generalized myasthenia gravis (75% vs. 39%). Respiratory involvement was associated with twice the mortality rate (60% vs. 33%) and triple the risk of noncomplete symptom resolution (20% vs. 61%). The majority of cases had their pembrolizumab discontinued (n=20, 71%), but 3 were successfully rechallenged by utilizing prophylactic low-dose steroids. Patients with immune-related myasthenia gravis experience increased mortality and morbidity but if steroid-responsive, may benefit from the reintroduction of anti-programmed cell death protein 1 therapy for end-stage malignancy with close monitoring. A high index of clinical suspicion for immune-related adverse effects are critical in an era of rising immunotherapy use.

Plasma Exchange for Severe Immune-Related Adverse Events from Checkpoint Inhibitors: An Early Window of Opportunity?

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of several advanced malignancies leading to durable remission in a subset of patients. Their rapidly expanding use has led to an increased frequency of immune-related adverse events (irAEs). The pathogenesis of irAEs is poorly understood but may involve aberrant activation of T cells leading to inflammatory cytokine release or production of pathogenic antibodies leading to organ damage. Severe irAEs can be extremely debilitating and, in some cases, life threatening. IrAEs may not always be corticosteroid responsive or may require excessively high, often toxic, corticosteroid doses. Therapeutic plasma exchange (PLEX) is a treatment modality that has shown promising results for the management of certain severe irAEs, including irAEs that are not mentioned in current treatment guidelines. PLEX may attenuate ongoing irAEs and prevent delayed irAEs by accelerating clearance of the ICI, or by acutely removing pathogenic antibodies, cytokines, and chemokines. Here, we summarize examples from the literature in which PLEX was successfully used for the treatment of irAEs. We posit that timing may be a critical factor and that earlier utilization of PLEX for life-threatening irAEs may result in more favorable outcomes. In individuals at high risk for irAEs, the availability of PLEX as a potential therapeutic mitigation strategy may encourage life-saving ICI use or rechallenge. Future research will be critical to better define which indications are most amenable to PLEX, particularly to establish the optimal place in the sequence of irAE therapies and to assess the ramifications of ICI removal on cancer outcomes.

Exploring the Mechanisms Underlying the Cardiotoxic Effects of Immune Checkpoint Inhibitor Therapies

Adaptive immune response modulation has taken a central position in cancer therapy in recent decades. Treatment with immune checkpoint inhibitors (ICIs) is now indicated in many cancer types with exceptional results. The two major inhibitory pathways involved are cytotoxic T-lymphocyte-associated protein 4 (CTLA4) and programmed cell death protein 1 (PD-1). Unfortunately, immune activation is not tumor-specific, and as a result, most patients will experience some form of adverse reaction. Most immune-related adverse events (IRAEs) involve the skin and gastrointestinal (GI) tract; however, any organ can be involved. Cardiotoxicity ranges from arrhythmias to life-threatening myocarditis with very high mortality rates. To date, most treatments of ICI cardiotoxicity include immune suppression, which is also not cardiac-specific and may result in hampering of tumor clearance. Understanding the mechanisms behind immune activation in the heart is crucial for the development of specific treatments. Histological data and other models have shown mainly CD4 and CD8 infiltration during ICI-induced cardiotoxicity. Inhibition of CTLA4 seems to result in the proliferation of more diverse T0cell populations, some of which with autoantigen recognition. Inhibition of PD-1 interaction with PD ligand 1/2 (PD-L1/PD-L2) results in release from inhibition of exhausted self-recognizing T cells. However, CTLA4, PD-1, and their ligands are expressed on a wide range of cells, indicating a much more intricate mechanism. This is further complicated by the identification of multiple co-stimulatory and co-inhibitory signals, as well as the association of myocarditis with antibody-driven myasthenia gravis and myositis IRAEs. In this review, we focus on the recent advances in unraveling the complexity of the mechanisms driving ICI cardiotoxicity and discuss novel therapeutic strategies for directly targeting specific underlying mechanisms to reduce IRAEs and improve outcomes.

Clinical Characteristics and Outcomes in Immune Checkpoint Inhibitor Therapy-Associated Myocarditis

Immune checkpoint inhibitor (ICI) therapy has played an important role in the treatment of several groups of cancers. Although a life prolonging treatment, many side effects have been shown with ICI therapy. This study looked at individual level clinical characteristics and outcomes with ICI therapy in patients who developed ICI-related myocarditis. A comprehensive review of the National Library of Medicine PubMed database was performed. Inclusion criteria were all studies that were composed of case reports and case series of individual patients undergoing ICI therapy that developed myocarditis. To appreciate individual patient level data, observational studies, clinical trials, systematic reviews, and meta-analyses were excluded. Our search yielded 333 results with 71 cases reviewed of ICI therapy-related myocarditis. The findings included an average age of 68 years, higher incidence in men, and pretreatment cardiac history of hypertension. Melanoma was the most prevalent malignancy with nivolumab being the most used ICI therapy. Heart failure was the most prevalent adverse event that was co-prevalent with myocarditis. Corticosteroid therapy alone was the most utilized therapy to treat ICI-related myocarditis. Mortality was seen in nearly half of the patient population. Our study reviewed the preexisting literature of prior reported myocarditis secondary to ICI therapy. Periodic surveillance should be performed by the cardio-oncologist and internist. Due to the expanding role of ICI therapy in treating a variety of cancer patients, appreciation of its impact on the development of myocarditis is needed.

Cardiac Toxicities Associated with Immune Checkpoints Inhibitors: Mechanisms, Manifestations and Management

Immune checkpoint inhibitor (ICI) associated cardiovascular adverse events (CVAE) have become more frequent with the growing use of cancer immunotherapy. CVAEs include a wide spectrum of diseases such as myocarditis, pericarditis, heart failure, arrhythmias, coronary artery disease, and hypertension. The induction of cardiovascular side effects by ICI use is hypothesized to occur due to inflammation and immune dysregulation of normal tissue in response to immunotherapy. Management of ICI-associated CVAEs mitigates an overactive immune response by utilizing steroids, immunomodulatory drugs and hemodynamic stabilization. However, few controlled studies on the cardiovascular safety of ICIs exist and treatment of their side effects are mostly from limited case series. Our review seeks to provide the most recent understanding of ICI-associated CVAEs and their management.