Immune checkpoint inhibitor-related myositis and myocarditis in patients with cancer

Pembrolizumab-associated Neuronopathy with Improved Lower Limb Somatosensory Evoked Potential After Intravenous Methylprednisolone Treatment

Cases of neuronopathy associated with immune checkpoint inhibitors (ICIs) have rarely been reported. We herein report a case of ICI-associated neuronopathy. A 54-year-old man underwent chemotherapy for right maxillary sinus cancer. Two months after pembrolizumab treatment, diarrhea, worsening of abnormal sensations, and severe ataxia of the lower limbs were observed. Somatosensory evoked potentials (SEPs) with tibial nerve stimulation showed disappearance of the N21 waveform. A colonic biopsy suggested ICI-associated colitis. Based on these findings, the patient was diagnosed with ICI-associated neuronopathy. Clinical symptoms and SEP findings improved markedly after two courses of intravenous methylprednisolone.

Immune Checkpoint Inhibitor-Related Myocarditis With or Without Concomitant Myopathy: Clinical Findings and Cardiovascular Outcomes

BACKGROUND

Data on cardiovascular outcomes in patients with both immune checkpoint inhibitor-induced immune-related myocarditis (irMyocarditis) and immune-related myopathy (irMyopathy) are limited.

OBJECTIVES

The aim of this study was to describe clinical characteristics and cardiovascular outcomes in patients with isolated irMyocarditis vs those with concomitant irMyocarditis and irMyopathy.

METHODS

A retrospective cohort study was conducted among patients diagnosed with irMyocarditis at Massachusetts General Brigham between 2015 and 2023. Clinical, laboratory, and imaging characteristics were evaluated, and cardiovascular outcomes were compared between patients with and those without concomitant irMyopathy. The outcomes assessed included acute heart failure requiring diuresis, significant arrhythmias (ventricular arrhythmias and high-degree atrioventricular block), and cardiovascular and all-cause mortality during the index hospitalization.

RESULTS

Among 101 patients with irMyocarditis, 32 (31.7%) had concomitant irMyopathy. Patients with irMyocarditis and irMyopathy had higher high-sensitivity troponin T (median 716 ng/L vs 75 ng/L; P < 0.001) and creatine kinase levels (median 3441 U/L vs 232 U/L; P < 0.001) and were more likely to present with significant arrhythmias (HR: 2.12; 95% CI: 1.13-3.97; P = 0.019). Conversely, patients with isolated irMyocarditis had higher N-terminal prohormone of brain natriuretic peptide levels (median 2043 pg/mL vs 606 pg/mL; P = 0.007), lower left ventricular ejection fractions (median 56% vs 65%; P = 0.008), and a higher likelihood of acute decompensated heart failure (HR: 5.88; 95% CI: 1.45-25; P = 0.013). Cardiovascular and all-cause death during admission were numerically higher in patients with concomitant irMyopathy but were not significantly different between the 2 groups.

CONCLUSIONS

Patients with irMyocarditis and irMyopathy and those with isolated irMyocarditis have distinct biomarker profiles and cardiovascular complications. These differences should be confirmed in larger prospective cohorts to guide tailored management strategies.

Immune checkpoint inhibitors mediate myocarditis by promoting macrophage polarization via cGAS/STING pathway

BACKGROUND

Immune checkpoint inhibitors has opened up new avenues for cancer treatment, but serious cardiac injury has emerged in their use. A large number of data have shown that abnormal activation of cytosolic DNA-sensing cyclic GMP-AMP synthase-interferon gene activator pathway is closely related to cardiovascular inflammation and autoimmune diseases. However, the pathophysiological function of the cGAS-STING cascade in myocarditis induced by Immune checkpoint inhibitors is unclear.

METHODS

In order to establish a Immune checkpoint inhibitors-associated myocarditis model, BALB/c mice were injected with mouse cardiac troponin I peptide and anti-mouse programmed death 1 antibody. Echocardiography and HE staining were then performed to assess cardiac function and inflammation. Macrophages and damaged DNA in mouse heart tissue were detected by immunofluorescence. The mitochondrial damage of macrophages was observed by electron microscope. In vitro experiments, RAW264.7 was used to detect macrophage polarization after anti-PD-1 antibody induction and STING inhibition by qPCR and flow cytometry. Mitochondrial damage was detected by immunofluorescence, and activation of the cGAS-STING signaling pathway was evaluated by protein imprinting analysis.

RESULTS

In the Immune checkpoint inhibitors-associated myocarditis model, DNA damage was found to activate the cGAS-STING pathway and macrophages were polarized to M1 type. In vitro experiments, anti-PD-1 antibody activate the cGAS-STING pathway through the release of damaged DNA from macrophage mitochondrial damage, causing macrophage polarization into a pro-inflammatory phenotype leading to autoimmune myocarditis.

CONCLUSION

Our results suggested that the cGAS-STING pathway played a key role in myocarditis caused by immune checkpoint inhibitors. It provided a new possibility for Immune checkpoint inhibitors to be widely used in clinic.

Features of myositis and myasthenia gravis in patients treated with immune checkpoint inhibitors: a multicentric, retrospective cohort study

Background

Immune checkpoint inhibitors (ICIs) may induce overlapping myositis/myasthenia gravis (MG) features, sparking current debate about pathophysiology and management of this emerging disease entity. We aimed to clarify whether ICI-induced (ir-) myositis and ir-MG represent distinct diseases or exist concurrently.

Methods

We performed a retrospective multicenter cohort study. Using the Paris University Hospitals database (n = 2,910,417), we screened all patients with International Classification of Diseases codes or free text related to myositis/MG signs and ICI (n = 620). 'Ir-MG signs' were defined by fatigability, repetitive nerve stimulation (RNS) decrement, and/or acetylcholine receptor antibodies (AChR Abs).

Findings

Ir-MG signs were never observed in the absence of ir-myositis (pathological diagnosis (n = 12/14) or CK levels >8000 U/L (n = 2/14)). Among ir-myositis patients, fatigability (2%; n = 1/62) and RNS decrement (2%; n = 1/41) were demonstrated only in one patient with pre-existing MG. AChR Abs testing yielded positive results in 26% of ir-myositis patients (n = 14/53). We revealed that test results were already positive prior to ICI therapy (n = 8/9). Clinically, ir-myositis frequently presented with "MG-like" oculomotor disease (50%; n = 31/62), bulbar dysfunction affecting speech (29%; n = 18/62) and swallowing (42%; n = 26/62), and respiratory disorders (53%; n = 33/62). Extraocular and diaphragm muscles necropsies disclosed intense muscle inflammation (100%; n = 5/5).

Interpretation

In our extensive database, we found no evidence of isolated ir-MG, nor of clear neuromuscular junction dysfunction in ir-myositis. These findings suggest that patients with ir-MG suspicion frequently have ir-myositis and ir-MG might be rare. "MG-like" symptoms may stem from ir-myositis-specific predilection for oculo-bulbo-respiratory musculature. Indeed, we revealed florid inflammatory infiltration of the oculomotor and respiratory muscles. Additional studies are needed to confirm these results and to elucidate the role of pre-existing AChR Abs in ir-myositis.

Funding

None.

Case report: A severe myositis mimicking bulbar palsy after administration of immune checkpoint inhibitors

Objectives

Immune Checkpoint Inhibitors (ICI) are nowadays a cornerstone of anti-cancer treatments. However, the wide spectrum of immune-related adverse events (irAEs) represents a challenge in the oncological practice. Our objective is to document rare complications of ICI to help the community of onco-immunologists.

Methods

We reported the case of a severe myositis mimicking bulbar palsy treated in our Medical Oncology Department together with Internal Medicine Department. We present the clinical work-up (neurological exam, capillaroscopy) and the diagnostic tests (myositis specific and associated antibodies, nerve conduction study, electromyography) leading to this diagnosis. We also discussed the elimination of differential diagnoses (notably with normal MRI and cerebrospinal fluid analysis) and finally the clinical management of this severe irAE.

Results

A 57 years woman presented multiple sub-diaphragmatic adenopathies related with an advanced melanoma of unknown primary. She started a treatment with Ipilimumab (Ipi, anti CTLA-4) and Nivolumab (Nivo, anti PD-1) and presented at day 10 a grade IV myositis mimicking bulbar palsy with dysphonia, dysarthria and aphagia. In a multidisciplinary setting, she was treated with IV corticosteroids (methylprednisolone 1 mg/kg started at day 10, with a progressive decrease until 1 mg of prednisone in March 2024), IV immunoglobulins started at day 18 (1.5 g/kg in 2 days, administered monthly, with a progressive decrease and a cessation in June 2022), enteral nutrition, speech therapy and physical therapy, with noticeable improvement. After 4 years of follow-up, and only one infusion of Ipi/Nivo, the melanoma is still in complete response.

Conclusion

We report an ICI-induced severe myositis mimicking bulbar palsy after the administration of Ipi/Nivo. The diagnosis and clinical care management of this rare complication requires a multi-disciplinary work-up.

Central nervous system complications of immune checkpoint inhibitors: A comprehensive review

The ever-increasing use of immune checkpoint inhibitors (ICIs) has significantly improved cancer management, but at the cost of frequent immunologic side effects. Among them, neurologic immune-related adverse events (nirAEs) are less common but pose a challenge to clinicians due to their severity, heterogeneous nature and nonspecific clinical presentation, making diagnosis complex. The prognosis of these nirAEs, especially those related to the central nervous system (CNS), correlates with their rapid recognition and therapeutic management. Indeed, the therapeutic options are sometimes unfamiliar and may be further complicated by the lack of recommendations in the event of failure of a well-managed first-line treatment. Finally, the attribution of ICIs to certain CNS disorders is controversial and may lead to an incorrect decision to discontinue or contraindicate treatment, resulting in an irremediable loss of opportunity for the patient. Therefore, the aim of this review is to present known/suspected CNS nirAEs induced by ICI, their diagnostic approach and management through therapeutic advices for optimal treatment and rechallenge opportunities.

Myositis associated with pembrolizumab presenting with myastheniform symptoms: two case reports

Immune checkpoint inhibitors (ICIs), such as pembrolizumab, have revolutionized cancer treatment by enhancing the immune system's response to malignancies. However, these therapies are associated with immune-related adverse events (irAEs), including neuromuscular complications such as myasthenia gravis, myositis, and myocarditis. We describe two male patients, aged 67 and 68, with small cell and non-small cell lung cancers, who developed progressive neuromuscular symptoms, including ptosis, diplopia, and generalized weakness, after receiving pembrolizumab. Clinical, biochemical, imaging, and electrophysiological findings confirmed the diagnosis of myositis with myastheniform features, with one case also involving myocarditis. Both patients underwent treatments with intravenous immunoglobulin (IVIg), pyridostigmine, and corticosteroids. The first patient, despite aggressive treatment including plasma exchange and rituximab, succumbed to complications from aspiration pneumonia. The second patient showed partial response to pyridostigmine and IVIg but later died due to metastatic cancer progression. A literature review revealed 52 cases of pembrolizumab-associated myositis with myastheniform symptoms, emphasizing its high morbidity and the need for vigilant monitoring. Pembrolizumab-associated myositis with myastheniform symptoms, especially when accompanied by myocarditis, presents a significant clinical challenge with high mortality. Early recognition and aggressive management of these irAEs are crucial to improving outcomes in cancer patients receiving ICIs.

Immune Checkpoint Inhibitor Myopathy: The Double-Edged Sword of Cancer Immunotherapy

Immune checkpoint inhibitor (ICI) therapy has revolutionized the treatment of several malignancies, with improved survival. These monoclonal antibodies target immune checkpoints, including cytotoxic T-lymphocyte-associated protein 4 (ipilimumab and tremelimumab), programmed death 1 (nivolumab, pembrolizumab, cemiplimab, and dostarlimab), programmed death ligand 1 (atezolizumab, avelumab, and durvalumab), and lymphocyte activation gene 3 (relatlimab), and effectively augment the immune response against tumor cells. Releasing the brakes on the immune system has consequences, however, in the form of immune-related adverse events (irAEs), which may affect any organ. Neurologic irAEs represent 1%-3% of all irAEs, with immune-mediated myopathy (ICI myopathy) being the most common manifestation. Recent large patient series and systematic reviews have established the key features and highlighted new insights into ICI myopathy. ICI myopathy is characterized by an acute or subacute onset of oculobulbar and/or proximal limb weakness, with or without associated respiratory insufficiency and myocarditis. Creatine kinase elevation is common. Oculobulbar presentations with or without respiratory failure may be misattributed to neuromuscular junction disorders, particularly because acetylcholine receptor antibodies are present in up to 40% of patients; however, an electrodiagnostic evidence of a defect of neuromuscular transmission is often absent even in patients with severe weakness, highlighting that the myopathic process is the driving force behind these presentations. Muscle histopathology commonly demonstrates a unique signature of multifocal clusters of necrotic and regenerating fibers, differentiating ICI myopathy from other autoimmune myopathies. Transcriptomic analysis has uncovered distinct subgroups within ICI myopathy, revealing varying degrees of type 1 and type 2 interferon pathway activation alongside notable upregulation of the interleukin (IL)-6 pathway in affected muscle tissue. This discovery presents a promising avenue for intervention through the use of therapies that suppress the interferon pathway and target IL-6 or its receptor. Despite clinical improvements with immunomodulatory therapy, with corticosteroids the mainstay of treatment, mortality remains high, particularly in those with associated myocarditis or respiratory failure requiring intubation, where mortality occurs in up to 50%. ICI withdrawal can lead to cancer progression and death, highlighting a need for improved approaches to ICI rechallenge, performed in limited patients with variable success to date.

Immune checkpoint inhibitors-associated cranial nerves involvement: a systematic literature review on 136 patients

OBJECTIVE

Describe the demographic data and clinical phenotype of cranial palsy induced by immune checkpoint inhibitors (CNP-ICI).

METHODS

A systematic literature review of the literature was performed in Pubmed, Web of Science, and Embase, including 68 articles and 136 patients (PROSPERO no. CRD42024517262).

RESULTS

Out of the 1205 articles screened, 68 articles were included after fulfilling the inclusion criteria, for a total of 136 patients. All articles were case reports and case series. In the cohort studied, 52% of patients were treated with anti PD-1/PDL-1 therapies, 14% with anti CTLA-4 therapies, and 34% with a combination of anti CTLA-4 and anti PD-1/PDL-1 therapies. The facial nerve was the most affected cranial nerve, involved in 38% of cases, followed by the optic nerve (35%), the cochleovestibular nerve (12%), and the abducens nerve (10%). The median time from the initial immune checkpoint inhibitor (ICI) injection to the onset CNP-ICI was 10 weeks (IQR 4-20). Magnetic resonance imaging demonstrated contrast enhancement or abnormal signal of the affected nerve in 43% of cases. Cerebrospinal fluid analysis indicated lymphocytic pleocytosis in 59% of cases. At the onset of immune-related adverse events, 89% of patients discontinued immunotherapy, and 92% received treatment for CNP-ICI. Treatment regimens included corticosteroids in 86% of cases, intravenous immunoglobulin in 21%, and plasma exchange in 5.1%. Among the whole population, 33% achieved recovery, 52% showed clinical improvement, 16% remained stable, and 3% experienced worsening of their condition. Rechallenge with immunotherapy was significantly associated with the emergence of new immune-related Adverse Events (irAEs).

CONCLUSION

ICI therapy may lead to cranial nerve involvement, particularly affecting the facial nerve, typically presenting around 10 weeks after treatment initiation. While corticosteroid therapy often resulted in patient improvement, rechallenging with ICIs were associated with new irAEs.

Clinical and pathological aspects of toxic myopathies

As the most frequent cause of acquired myopathy, toxic myopathies are characterised by clinicopathological features that vary depending on the mode of action of the drugs or toxins involved. Although a large number of substances can induce myotoxicity, the main culprits are statins, alcohol, and corticosteroids. A rigorous, well-organised diagnostic approach is necessary to obtain a rapid diagnosis. For early diagnosis and management, it is important for clinicians to be aware that most toxic myopathies are potentially reversible, and the goal of treatment should be to avoid serious muscle damage.

Peripheral nervous system immune-related adverse events due to checkpoint inhibition

Immune checkpoint inhibitors have revolutionized cancer therapy and are increasingly used to treat a wide range of oncological conditions, with dramatic benefits for many patients. Unfortunately, the resulting increase in T cell effector function often results in immune-related adverse events (irAEs), which can involve any organ system, including the central nervous system (CNS) and peripheral nervous system (PNS). Neurological irAEs involve the PNS in two-thirds of affected patients. Muscle involvement (immune-related myopathy) is the most common PNS irAE and can be associated with neuromuscular junction involvement. Immune-related peripheral neuropathy most commonly takes the form of polyradiculoneuropathy or cranial neuropathies. Immune-related myopathy (with or without neuromuscular junction involvement) often occurs along with immune-related myocarditis, and this overlap syndrome is associated with substantially increased mortality. This Review focuses on PNS adverse events associated with immune checkpoint inhibition. Underlying pathophysiological mechanisms are discussed, including antigen homology between self and tumour, epitope spreading and activation of pre-existing autoreactive T cells. An overview of current approaches to clinical management is provided, including cytokine-directed therapies that aim to decouple anticancer immunity from autoimmunity and emerging treatments for patients with severe (life-threatening) presentations.

Paraneoplastic Neurologic Disorders

OBJECTIVE

This article reviews the clinical presentations, neural antibody associations, and oncologic accompaniments of paraneoplastic neurologic syndromes and neurologic autoimmunity in the context of immune checkpoint inhibitor (ICI) cancer immunotherapy.

LATEST DEVELOPMENTS

Neural antibody discovery has improved the diagnosis of paraneoplastic neurologic syndromes. Neural antibodies also delineate the underlying disease pathophysiology and thus inform outcomes and treatments. Neural antibodies specific for extracellular proteins have pathogenic potential, whereas antibodies specific for intracellular targets are biomarkers of a cytotoxic T-cell immune response. A recent update in paraneoplastic neurologic syndrome criteria suggests high- and intermediate-risk phenotypes as well as neural antibodies to improve diagnostic accuracy in patients with paraneoplastic neurologic syndromes; a score was created based on this categorization. The introduction of ICI cancer immunotherapy has led to an increase in cancer-related neurologic autoimmunity with distinct clinical phenotypes.

ESSENTIAL POINTS

Paraneoplastic neurologic syndromes reflect an ongoing immunologic response to cancer mediated by effector T cells or antibodies. Paraneoplastic neurologic syndromes can present with manifestations at any level of the neuraxis, and neural antibodies aid diagnosis, focus cancer screening, and inform prognosis and therapy. In patients with high clinical suspicion of a paraneoplastic neurologic syndrome, cancer screening and treatment should be undertaken, regardless of the presence of a neural antibody. ICI therapy has led to immune-mediated neurologic complications. Recognition and treatment lead to improved outcomes.

Rheumatic adverse events of immune checkpoint inhibitors in cancer immunotherapy

INTRODUCTION

The advent of immune checkpoint inhibitors (ICIs) in cancer treatment has marked a transformative era, albeit tempered by immune-related adverse events (irAEs), including those impacting the musculoskeletal system. The lack of precise epidemiologic data on rheumatic irAEs is attributed to factors such as potential underrecognition, underreporting in clinical trials, and the tendency to overlook manifestations without immediate life-threatening implications, further complicating the determination of accurate incidence rates, while the complete understanding of the mechanisms driving rheumatic irAEs remains elusive.

AREAS COVERED

This literature review comprehensively examines rheumatic irAEs in cancer patients undergoing ICI therapy, encompassing epidemiology, risk factors, mechanisms, clinical manifestations, and current management guidance for prevalent conditions such as inflammatory arthritis, polymyalgia rheumatica, and myositis. Less frequent rheumatic and musculoskeletal irAEs are also explored, alongside insights into ongoing clinical trials testing therapeutic and preventive strategies for irAEs. A thorough literature search on Medline and the National Cancer Institute Clinical Trials Database was conducted up to October 2023 to compile relevant information.

EXPERT OPINION

In light of the evolving landscape of cancer immunotherapy, there is a compelling need for prospective longitudinal studies to enhance understanding and inform clinical management strategies for rheumatic irAEs.

Unravelling the Acute, Chronic and Steroid-Refractory Management of High-Grade Neurological Immune-Related Adverse Events: A Call to Action

Rare side effects of immune-checkpoint inhibitors (ICIs) are known as neurological immune-related adverse events (n-irAEs). Typically, n-irAEs affect the peripheral nervous system, primarily presenting as myositis, polyradiculoneuropathy, or cranial neuropathy. Less commonly, they impact the central nervous system, resulting in encephalitis, meningitis, or myelitis. High-grade n-irAEs managing and recognizing remains challenging, considering the risk of mortality and long-term disability. To date, strong scientific data are lacking to support the management of high-grade clinical forms. We performed a systematic literature search, selecting all articles describing high-grade steroid-resistance n-irAEs. and we reported them in a practical review. Specifically, current recommendations advise stopping ICI use and beginning corticosteroid treatment. Our findings highlighted that in steroid-resistant n-irAEs, it should be recommended to quickly escalate to plasma exchange (PLEX) and/or intravenously immunoglobulins (IVIg), usually in association with other immunosuppressants. Furthermore, newer evidence supports the use of drugs that may specifically block inflammation without reducing the anti-tumour effect of ICIs. In this practical review, we provide new evidence regarding the therapeutic approach of high-grade n-irAEs, particularly in steroid-resistant cases. We would also stress the importance of informing the scientific community of the discrepancy between current guidelines and clinical evidence in these rare forms of pathology.

A case report of immune checkpoint inhibitor-related myositis and cholangitis induced by pembrolizumab

Key Clinical Message

Rare but severe, immune-related adverse events such as myositis and sclerosing cholangitis can occur with immune checkpoint inhibitors in lung cancer treatment. This case report highlights their co-occurrence after pembrolizumab treatment, indicating the need for vigilance and management strategies in immune checkpoint inhibitors therapy.

Abstract

Immune checkpoint inhibitors (ICI) are used in advanced treatment of lung cancer but can lead to immune-related adverse events. ICI-related myositis and cholangitis are rare, and their combination has not been previously reported. Here, we report the first case of ICI-related myositis and sclerosing cholangitis. A patient with stage IV lung adenocarcinoma who received one cycle of pembrolizumab with cisplatin and pemetrexed developed myositis. Treatment with prednisolone improved the myositis, but the patient subsequently developed cholangitis. The patient did not respond to a regimen of prednisolone, mycophenolate mofetil, and azathioprine, and eventually died due to worsening lung cancer. An autopsy confirmed the presence of ICI-related myositis and sclerosing cholangitis.

Immune checkpoint inhibitor-induced myasthenia gravis, myocarditis, and myositis: A case report

Key Clinical Message

Immune checkpoint inhibitors can rarely lead to occurrence of myositis, myocarditis, and myasthenia gravis (MG). Early recognition and multidisciplinary management are crucial for optimal outcomes. Vigilance for overlapping toxicities is essential in patients receiving combination immunotherapy.

Abstract

The use of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment, but it is associated with immune-related adverse events (IRAEs) affecting various organ systems. The simultaneous occurrence of MG, myocarditis, and myositis highlights the complex nature of IRAEs. Early recognition and comprehensive multidisciplinary management are crucial for optimal patient outcomes. We present a unique case report of a 76-year-old male patient with advanced melanoma who developed concurrent myositis, myocarditis, and MG while receiving combination immunotherapy with Nivolumab and Ipilimumab. This case underscores the significance of recognizing and addressing the "Terrible Triad" of IRAEs in patients receiving ICIs. Healthcare providers should maintain a high index of suspicion for overlapping toxicities and promptly initiate appropriate interventions.

Treatment patterns and survival outcomes of patients admitted to the intensive care unit due to immune-related adverse events of immune checkpoint inhibitors

INTRODUCTION

Severe immune-related adverse events (irAEs) due to immune checkpoint inhibitors (ICIs) can lead to admission to the intensive care unit (ICU). In this retrospective study, we determined the incidence, treatment patterns and survival outcomes of this patient population at a comprehensive cancer center.

METHODS

All patients admitted to the ICU due to irAEs from ICI treatment between January 2015 and July 2022 were included. Descriptive statistics were reported on patient characteristics and treatment patterns during hospital admission. Overall survival (OS) from the time of ICU discharge to death was estimated using the Kaplan-Meier method.

RESULTS

Over the study period, 5561 patients received at least one ICI administration, of which 32 patients (0.6%) were admitted to the ICU due to irAEs. Twenty patients were treated with anti-PD-1 plus anti-CTLA-4 treatment, whereas 12 patients were treated with ICI monotherapy. The type of irAEs were de novo diabetes-related ketoacidosis (n = 8), immune-related gastrointestinal toxicity (n = 8), myocarditis or myositis (n = 10), nephritis (n = 3), pneumonitis (n = 2), and myelitis (n = 1). The median duration of ICU admission was 3 days (interquartile range: 2-6 days). Three patients died during ICU admission. The median OS of the patients who were discharged from the ICU was 18 months (95% confidence interval, 5.0-NA).

CONCLUSION

The incidence of irAEs leading to ICU admission in patients treated with ICI was low in this study. ICU mortality due to irAEs was low and a subset of this patient population even had long-term survival.

The Utility of Laboratory Investigations for the Assessment and Management of Rheumatic Immune Related Adverse Events

Immune checkpoint inhibitors (ICIs) have greatly improved survival of several cancers with historically very poor prognosis. ICIs act by stimulating the patient's own immune system to fight cancer. Simultaneously, this immune activation can lead to immune-related adverse events (irAEs), including rheumatic manifestations (Rh-irAEs). Rh-irAEs mimic primary rheumatic diseases including arthritis, polymyalgia rheumatica, myositis, vasculitis, sarcoidosis, and sicca. This article summarizes the latest evidence regarding the utility of laboratory investigations in Rh-irAEs.

Immune-Mediated Necrotizing Myopathies: Current Landscape

PURPOSE OF REVIEW

Immune-mediated necrotizing myopathy (IMNM), characterized by acute or subacute onset, severe weakness, and elevated creatine kinase levels, poses diagnostic and therapeutic challenges. This article provides a succinct overview of IMNM, including clinical features, diagnostic strategies, and treatment approaches.

RECENT FINDINGS

Recent insights highlight the different clinical presentations and therapeutic options of IMNM stratified by autoantibody positivity and type. Additionally, recent findings call into question the reported link between statin use and IMNM. This review synthesizes current knowledge on IMNM, emphasizing its distinct clinical features and challenging management. The evolving understanding of IMNM underscores the need for a comprehensive diagnostic approach that utilizes a growing range of modalities. Early and aggressive immunomodulatory therapy remains pivotal. Ongoing research aims to refine diagnostic tools and therapeutic interventions for this challenging muscle disorder, underscoring the importance of advancing our understanding to enhance patient outcomes.

Immune Checkpoint Inhibitor-induced Myositis

Myositis induced by immune checkpoint inhibitors (ICIs) is an infrequent, potentially fatal, immune-related adverse event. It has higher incidence in patients who receive combination ICI therapy compared to monotherapy. Patients can present with clinical manifestation symptoms of myositis alone or in combination with myocarditis and/or myasthenia gravis, which significantly worsens the course and prognosis. Diagnosis can generally be made on the basis of clinical presentation, elevation of muscle enzymes, and electromyographic changes, but some patients may require a muscle biopsy. The first line of therapy is high-dose corticosteroids, followed by immunosuppression, plasmapheresis, or intravenous immunoglobulin in patients with severe disease.

Drug-Induced Myopathies: A Comprehensive Review and Update

Drug-induced myopathies are a common cause of muscle pain, and the range of drugs that can cause muscle side effects is constantly expanding. In this article, the authors comprehensively discuss the diagnostic and therapeutic process in patients with myalgia, and present the spectrum of drug-induced myopathies. The review provides a detailed analysis of the literature on the incidence of myopathy during treatment with hypolipemic drugs, beta-blockers, amiodarone, colchicine, glucocorticosteroids, antimalarials, cyclosporine, zidovudine, and checkpoint inhibitors, a group of drugs increasingly used in the treatment of malignancies. The article considers the clinical course of the different types of myopathies, their pathogenesis, histopathological features, and treatment methods of these disorders. The aim of this paper is to gather from the latest available literature up-to-date information on the course, pathophysiology, and therapeutic options of drug-induced myopathies, to systematize the knowledge of drug-induced myopathies and to draw the attention of internists to the fact that these clinical issues are an important therapeutic problem.

Immune checkpoint inhibitor related myositis: an observational, retrospective, pharmacovigilance study

BACKGROUND

Immune checkpoint inhibitors (ICIs) show promise in cancer treatment, but recent cases highlight myositis as a serious complication.

RESEARCH DESIGN AND METHODS

We did a retrospective study on drug safety using FAERS data up to Q3 2022, focusing on immune checkpoint inhibitors (ICIs) and myositis. We used IC and ROR to assess the association. Logistic regression in R 3.2.5 helped identify factors linked to fatal outcomes.

RESULTS

We identified 558 cases of ICIs-associated myositis. Our study found a significant link between ICIs and myositis (ROR 15.54 [14.23-16.96], IC 3.79 [3.66-3.92], see Figure 1). Notably, myositis was more common in patients on ICI combination therapy compared to monotherapy (ROR 1.72 [1.39-2.11], IC 0.63 [0.30-0.93]). Age increased the risk of ICI-associated myositis and was also a factor in fatality (p = 0.011). Common accompanying adverse events included myocarditis (21.33%), severe myasthenia gravis (16.49%), and malignant neoplasm progression (8.06%). Fatal cases were more common when myositis was accompanied by myocarditis, severe myasthenia gravis, or malignant neoplasm progression.

CONCLUSIONS

Clinicians must note the risk of ICI-associated myositis, especially dangerous in older patients or when combined with other issues like myocarditis or severe myasthenia gravis.

Neurological Adverse Events Related to Immune Checkpoint Inhibitors: A Practical Review

The increasing use of immune checkpoint inhibitors (ICI) in cancer therapy has brought attention to their associated neurotoxicities, termed neurological immune-related adverse events (n-irAEs). Despite their relatively rare incidence, n-irAEs pose a significant risk, potentially leading to severe, long-lasting disabilities or even fatal outcomes. This narrative review aims to provide a comprehensive overview of n-irAEs, focusing on their recognition and management. The review addresses a spectrum of n-irAEs, encompassing myositis, myasthenia gravis, various neuropathies, and central nervous system complications, such as encephalitis, meningitis, and demyelinating diseases. The key features of n-irAEs are emphasized in this review, including their early onset after initiation of ICIs, potential association with non-neurological irAEs and/or concurrent oncological response, the significance of ruling out other etiologies, and the expected improvement upon discontinuation of ICIs and/or immunosuppression. Furthermore, this review delves into considerations for ICI re-challenge and the intricate nature of n-irAEs within the context of pre-existing autoimmune and paraneoplastic syndromes. It underscores the importance of a multidisciplinary approach to diagnosis and treatment, highlighting the pivotal role of severity grading in guiding treatment decisions.

Immune-Related Adverse Events Due to Cancer Immunotherapy: Immune Mechanisms and Clinical Manifestations

The landscape of cancer treatment has undergone a significant transformation with the introduction of Immune Checkpoint Inhibitors (ICIs). Patients undergoing these treatments often report prolonged clinical and radiological responses, albeit with a potential risk of developing immune-related adverse events (irAEs). Here, we reviewed and discussed the mechanisms of action of ICIs and their pivotal role in regulating the immune system to enhance the anti-tumor immune response. We scrutinized the intricate pathogenic mechanisms responsible for irAEs, arising from the evasion of self-tolerance checkpoints due to drug-induced immune modulation. We also summarized the main clinical manifestations due to irAEs categorized by organ types, detailing their incidence and associated risk factors. The occurrence of irAEs is more frequent when ICIs are combined; with neurological, cardiovascular, hematological, and rheumatic irAEs more commonly linked to PD1/PD-L1 inhibitors and cutaneous and gastrointestinal irAEs more prevalent with CTLA4 inhibitors. Due to the often-nonspecific signs and symptoms, the diagnosis of irAEs (especially for those rare ones) can be challenging. The differential with primary autoimmune disorders becomes sometimes intricate, given the clinical and pathophysiological similarities. In conclusion, considering the escalating use of ICIs, this area of research necessitates additional clinical studies and practical insights, especially the development of biomarkers for predicting immune toxicities. In addition, there is a need for heightened education for both clinicians and patients to enhance understanding and awareness.

Prognosis of immune checkpoint inhibitor-induced myasthenia gravis: a single center experience and systematic review

Background

Immune checkpoint inhibitors (ICI)-induced myasthenia gravis (MG) is an uncommon but potentially fatal neurotoxicity. We aim to help physicians familiarize themselves with the clinical characteristics of ICI-induced MG, facilitating early diagnosis and prompt intervention.

Methods

We searched the Chinese People's Liberation Army General Hospital medical record system from January 2017 to August 2023 for patients diagnosed with ICI-induced MG. We systematically reviewed the literature until August 2023 to identify all similar patients. We collected clinical information on these patients.

Results

110 patients were identified, 9 from our institution and 101 from case reports. In our institution, Median age was 66 years (range: 49-79 years). 6 were males. The most common was lung cancer (n = 4). All patients had no previous history of MG and received PD-1 or PD-L1 inhibitors. The median time from ICI initiation to first MG symptoms was 4 weeks (range: 2-15 weeks). ICIs were discontinued in all patients. Most patients initially received high-dose corticosteroids, and their symptoms improved. Some patients are discharged with corticosteroids maintenance therapy. In addition, 55 patients (50%) with concomitant myositis and/or myocarditis and MG-induced mortality were more common in the myositis and/or myocarditis group (10.9% vs. 34.5%, p = 0.016). Overlap of myositis with MG (OR = 3.148, p = 0.009) and anti-AChR antibody positivity (OR = 3.364, p = 0.005) were both significantly associated with poor outcomes.

Conclusion

Our study reveals the prognosis of ICI-induced MG and suggests that myositis and/or myocarditis are severe comorbidities of ICI-induced MG, emphasizing the importance of early diagnosis and clinical intervention.

Immune checkpoint inhibitor-related myositis and myocarditis: diagnostic pitfalls and imaging contribution in a real-world, institutional case series

BACKGROUND

Immune checkpoint inhibitors (ICIs) are reshaping the prognosis of many cancers, but often cause immune-related adverse events (irAEs). Among neurological irAEs, myositis is the most frequently reported. Our aim is to describe clinical and non-clinical characteristics, treatment and outcome of all irMyositis (skeletal limb-girdle and/or ocular myositis) and irMyocarditis cases in our reference center.

METHODS

We retrospectively enrolled all irMyositis/irMyocarditis patients seen between 2018 and 2022. We reviewed demographics, clinical characteristics, biological, neurophysiological, imaging workup, treatment and outcome.

RESULTS

We included 14 consecutive patients. The most frequent treatments were pembrolizumab (35%) or ipilimumab-nivolumab combination (35%). Limb-girdle, ocular (non-fluctuating palpebral ptosis and/or diplopia with or without ophthalmoparesis) and cardiac phenotypes were equally distributed, overlapping in 40% of cases. Ocular involvement was frequently misdiagnosed; review of brain MRIs disclosed initially missed signs of skeletal myositis in one patient and ocular myositis in 3. Seven patients had other co-existing irAEs. When performed, myography showed a myogenic pattern. CK was elevated in 8/15 patients, troponin-T in 12/12 and troponin-I in 7/9 tested patients. ICI were discontinued in all cases, with further immunosuppressive treatment in nine patients. In most cases, neurological and cardiological outcome was good at last follow-up.

CONCLUSION

Myositis is a potentially severe irAE. Despite its heterogeneous presentation, some highly suggestive clinical symptoms, such as ocular involvement, or radiological signs should raise physicians' attention to avoid misdiagnosis. We thus recommend a multidisciplinary assessment (including complete neuromuscular evaluation) even in case of isolated myocarditis. Our series underlines the importance of an early diagnosis, since suspension of ICI and adequate treatment are usually associated with good functional outcome.

Cardiac magnetic resonance-based layer-specific strain in immune checkpoint inhibitor-associated myocarditis

AIMS

To assess the different imaging characteristics between corticosteroid-sensitive (CS) and corticosteroid-refractory (CR) immune checkpoint inhibitor-associated myocarditis (ICIaM) with cardiac magnetic resonance (CMR) and the potential CMR parameters in the early detection of CR ICIaM.

METHODS AND RESULTS

Thirty-five patients diagnosed with ICIaM and 30 age and gender-matched cancer patients without a history of ICI treatment were enrolled. CMR with contrast was performed within 2 days of clinical suspicion. Left ventricular ejection fraction (LVEF) and late gadolinium enhancement (LGE) were assessed by CMR. LV sub-endocardial (GLSendo) and sub-epicardial (GLSepi) global longitudinal strains were quantified by offline feature tracking analysis. CS and CR ICIaM were defined based on the trend of Troponin I and clinical course during corticosteroid treatment. All 35 patients presented with non-fulminant symptoms upon initial assessment. Twenty patients (57.14%) were sensitive, and 15 (42.86%) were refractory to corticosteroids. Compared with controls, 22 patients (62.86%) with ICIaM developed LGE. LVEF decreased in CR ICIaM compared with the CS group and controls. GLSendo (-14.61 ± 2.67 vs. -18.50 ± 2.53, P < 0.001) and GLSepi (-14.75 ± 2.53 vs. -16.68 ± 2.05, P < 0.001) significantly increased in patients with CR ICIaM compared with the CS ICIaM. In patients with CS ICIaM, although GLSepi (-16.68 ± 2.05 vs. -19.31 ± 1.80, P < 0.001) was impaired compared with the controls, GLSendo was preserved. There was no difference in CMR parameters between LGE-positive and negative groups. LVEF, GLSendo, and GLSepi were predictors of CR ICIaM. When LVEF, GLSendo, and GLSepi were included in multivariate analysis, only GLSendo remained an independent predictor of CR ICIaM (OR: 2.170, 95% CI: 1.189-3.962, P = 0.012). A GLSendo of ≥-17.10% (sensitivity, 86.7%; specificity, 80.0%; AUC, 0.860; P < 0.001) could predict CR ICIaM in the ICIaM cohort. Kaplan-Meier analysis showed that in patients with impaired GLSendo of ≥-17.10%, cardiovascular adverse events (CAEs) occurred much earlier than in patients with preserved GLSendo of <-17.10% (Log-rank test P = 0.017).

CONCLUSIONS

CR and CS ICIaM demonstrated different functional and morphological characteristics in different myocardial layers. An impaired GLSendo could be a helpful parameter in early identifying corticosteroid-refractory individuals in the ICIaM population.

The role of circulating biomarkers in predicting the 30-day mortality of immune checkpoint inhibitors-related myocarditis: a retrospective cohort study

Immune checkpoint inhibitors-related myocarditis (ICIs-M) is a rare and highly lethal immune-related adverse events (irAEs) in common irAEs. This study aims to find circulating biomarkers that can reflect disease state and prognosis accurately. 48 patients with ICIs-M were enrolled according to the diagnostic criteria for ICIs-related myocarditis. For all enrolled patients, valuable information was extracted retrospectively from the medical system, mainly including demographic information, tumor information and laboratory examination. The follow-up period was defined as 30 days after the first diagnosis of ICIs-M. In this study, the 30-day mortality rate of ICIs-M was 24.4%. After adjusting for potential confounding factors using multivariate analysis tools, we demonstrated the excellent performance of biomarkers in predicting 30-day mortality in patients with ICIs-M, including PLT (hazard ratio (HR), 1.07; 95% confidence interval (95%CI), 1.01-1.14; p = 0.028), ALT (HR, 1.23; 95%CI, 1.06-1.41; p = 0.005), AST(HR, 1.06; 95%CI, 1.01-1.10; p = 0.015), LDH (HR, 1.15; 95%CI, 1.04-1.26; p = 0.004), troponin I(HR, 1.44; 95%CI, 1.09-1.89; p = 0.009), PLR (blood plate/lymphocyte) (HR, 1.04; 95% CI, 1.01-1.07; p = 0.024), LAR (lactate dehydrogenase/albumin) (HR, 1.05; 95%CI, 1.01-1.09; p = 0.012), and AAR (aspartate transaminase/albumin) (HR, 1.18; 95%CI, 1.00-1.39; p = 0.048). The analysis of the receiver operating characteristic showed that biomarkers with area under curve (AUC) greater than or equal to 0.80 were LDH (cutoff value, 724.5; AUC, 0.86; 95%CI, 0.75-0.97), LAR (cutoff value, 18.11; AUC, 0.87; 95%CI, 0.76-0.97), troponin I (cutoff value, 0.87; AUC, 0.80; 95%CI, 0.62-0.99), and AAR(cutoff value, 1.52; AUC, 0.80; 95%CI, 0.61-0.98). LDH, LAR, troponin I, and AAR are a group of promising biomarkers that demonstrate excellent predictive ability in predicting the 30-day mortality rate of immune-related myocarditis.

The ABC of Immune-Mediated Hepatitis during Immunotherapy in Patients with Cancer: From Pathogenesis to Multidisciplinary Management

Immune-mediated hepatotoxicity (IMH) is not-so-rare complication during treatment with immune checkpoint inhibitors (ICIs). This narrative review aims to report the current knowledge on hepatic immune-related adverse events (irAEs) during immunotherapy from pathogenesis to multidisciplinary management. The majority of cases of IMH are asymptomatic and only a few patients may have clinical conditions. The severity of IMH is usually stratified according to Common Terminology for Clinical Adverse Events (CTCAE) criteria, but these scores may overestimate the clinical severity of IMH compared to the Drug-Induced Liver Injury Network (DILIN) scale. The differential diagnosis of IMH is challenging because the elevated liver enzymes can be due to a number of etiologies such as viral infection, autoimmune and metabolic diseases, liver metastases, biliary diseases, and other drugs. The cornerstones of IMH management are represented by withholding or delaying ICI administration and starting immunosuppressive therapy. A multidisciplinary team, including oncologists, hepatologists, internists, and emergency medicine physicians, is essential for the management of IMH.

Inaugural dropped head syndrome and camptocormia in inflammatory myopathies: a retrospective study

OBJECTIVES

Inaugural axial muscle involvement, defined as dropped head syndrome (DHS) and/or camptocormia (CC), is poorly described in inflammatory myopathies (IM). This study aimed to further characterize IM patients with inaugural DHS/CC, their outcome and care management.

METHODS

This retrospective study included IM patients diagnosed between 2000 and 2021. The main inclusion criterion was IM revealed by axial muscle deficit (DHS/CC).

RESULTS

Twenty-seven patients were included; median (IQR) age at first symptoms was 66.0 years (55.5-75.0); 21 were female (77.8%). There were nine IBM, 33.3%, nine overlap myositis (OM, 33.3%), five DM, 18.5%, two immune checkpoint inhibitor-related myositis (7.4%), one focal myositis (3.7%) and one myositis with anti-Hu antibodies (3.7%). Age at first symptoms was ≤70 years in 16 patients (59.3%), including all DM patients and 8/9 OM patients (88.9%). In this group, partial remission of the disease was obtained in 9/16 (56.3%) and complete remission in 1/16 patients (6.3%); regression of DHS/CC was achieved in 3/16 patients (18.8%). Conversely, in the group of 11 patients aged >70 years at first symptoms, there were eight IBM (72.7%). Partial remission was obtained in 5/11 patients (45.5%), the disease was stable in 6/11 patients (54.5%); no complete remission was obtained nor regression of DHS/CC.

CONCLUSION

The analysis of IM patients with inaugural DHS/CC delineates two groups of patients according to the age at first symptoms in terms of clinical and outcome specificities, and proposes an adapted diagnostic and care management approach to prevent long-term complications.

Complement and MHC patterns can provide the diagnostic framework for inflammatory neuromuscular diseases

Histopathological analysis stands as the gold standard for the identification and differentiation of inflammatory neuromuscular diseases. These disorders continue to constitute a diagnostic challenge due to their clinical heterogeneity, rarity and overlapping features. To establish standardized protocols for the diagnosis of inflammatory neuromuscular diseases, the development of cost-effective and widely applicable tools is crucial, especially in settings constrained by limited resources. The focus of this review is to emphasize the diagnostic value of major histocompatibility complex (MHC) and complement patterns in the immunohistochemical analysis of these diseases. We explore the immunological background of MHC and complement signatures that characterize inflammatory features, with a specific focus on idiopathic inflammatory myopathies. With this approach, we aim to provide a diagnostic algorithm that may improve and simplify the diagnostic workup based on a limited panel of stainings. Our approach acknowledges the current limitations in the field of inflammatory neuromuscular diseases, particularly the scarcity of large-scale, prospective studies that validate the diagnostic potential of these markers. Further efforts are needed to establish a consensus on the diagnostic protocol to effectively distinguish these diseases.

Neurologic manifestations of autoimmunity with immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) are cancer immunotherapies that enhance the body's own immune system to treat cancer. ICI treatment, however, can cause immune-related adverse events (irAEs) that can affect any organ, resulting in significant morbidity and mortality. Neurologic irAEs (nirAEs) are rare and can affect the peripheral nervous system more commonly than the central nervous system. Treatment is dependent on the severity of the neurologic manifestations and often includs discontinuation of the ICI and initiation of steroid therapy as the first line; other treatments have also been used. NirAEs and cardiac irAEs have higher fatality rates underlying the importance of early recognition and appropriate management. This chapter reviews the clinical manifestations of neurologic immune-related adverse events associated with ICI treatment as well as diagnostic and therapeutic modalities.

Neurological adverse events of immune checkpoint inhibitors and the development of paraneoplastic neurological syndromes

Immune checkpoint inhibitors, a class of oncological treatments that enhance antitumour immunity, can trigger neurological adverse events closely resembling paraneoplastic neurological syndromes. Unlike other neurological adverse events caused by these drugs, post-immune checkpoint inhibitor paraneoplastic neurological syndromes predominantly affect the CNS and are associated with neural antibodies and cancer types commonly found also in spontaneous paraneoplastic neurological syndromes. Furthermore, post-immune checkpoint inhibitor paraneoplastic neurological syndromes have poorer neurological outcomes than other neurological adverse events of immune checkpoint inhibitors. Early diagnosis and initiation of immunosuppressive therapy are likely to be crucial in preventing the accumulation of neurological disability. Importantly, the neural antibodies found in patients with post-immune checkpoint inhibitor paraneoplastic neurological syndromes are sometimes detected before treatment, indicating that these antibodies might help to predict the development of neurological adverse events. Experimental and clinical evidence suggests that post-immune checkpoint inhibitor paraneoplastic neurological syndromes probably share immunological features with spontaneous paraneoplastic syndromes. Hence, the study of post-immune checkpoint inhibitor paraneoplastic neurological syndromes can help in deciphering the immunopathogenesis of paraneoplastic neurological syndromes and in identifying novel therapeutic targets.

Immune Checkpoint Inhibition-Related Myasthenia-Myositis-Myocarditis Responsive to Complement Blockade

OBJECTIVE

Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy but come with immune-related adverse events (irAEs) that provide a novel challenge for treating physicians. Neuromuscular irAEs, including myositis, myasthenia gravis (MG), and demyelinating polyradiculoneuropathy, lead to significant morbidity and mortality.

METHODS

We present a case of severe myasthenia-myositis-myocarditis overlap in a patient receiving ICIs for breast cancer. Clinical findings were recorded.

RESULTS

A 47-year-old woman developed tetraparesis, dysphagia, and muscle pain during ICI treatment. MG with a thymoma had been diagnosed earlier. Neuromuscular overlap irAEs with cardiac affection was confirmed, and ICI treatment was discontinued. Given a lack of clinical response to standard therapies, a muscle biopsy was performed demonstrating complement deposition. Eculizumab treatment led to rapid improvement in muscle strength and cardiac function.

DISCUSSION

Neuromuscular irAEs are associated with a high in-hospital mortality, and specific treatment strategies remain an unmet need. Here, early muscle biopsy enabled targeted therapy after standard approaches failed, thereby highlighting the value of identifying a specific treatment target. To improve therapeutic outcomes, the development of patient-tailored strategies for neuromuscular irAEs requires further studies.

The Role of Environmental Factors in the Development of Idiopathic Inflammatory Myopathies: a Narrative Review

PURPOSE OF REVIEW

This review aims to evaluate recent findings on the role of environmental factors in the development and clinical presentation of idiopathic inflammatory myopathies (IIMs).

RECENT FINDINGS

A targeted literature review was conducted to identify reports relevant to the association between environmental factors and IIMs published over the past three years. There has been an increasing number of publications dealing with the association of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or vaccination with the development of IIMs, highlighting the significant role of the antiviral immune response in the pathogenesis of the disease. Traditional environmental factors associated with the pathogenic process of IIM subclassifications included drugs such as statins and immune checkpoint inhibitors, ultraviolet radiation, smoking, air pollutants, and vitamin D deficiency. Correlations of seasonality and residence with the onset of certain IIM subtypes suggest a potential role of environmental triggers in the pathogenic process. An interplay between genetic predisposition and various environmental factors might contribute to the development of IIMs as well as the heterogeneous clinical and serological presentation of IIMs. The growing evidence on the role of environmental factors in the development of IIMs provides important clues to elucidate the pathophysiology of these disease entities. The mechanisms underlying the interactions between genetic predisposition and environmental factors should be investigated in the future.

Advances of autoimmune rheumatic diseases related to malignant tumors

BACKGROUND

Malignant neoplasms are a well-recognized global public health concern, with significant impacts on human health and quality of life. The interplay between tumors and autoimmune rheumatic diseases is complex, and the resulting tumor-associated rheumatic diseases represent a rare and intricate group of conditions that occur in the context of malignant tumors. In addition, various rheumatic diseases can arise as a consequence of oncology treatment. These diseases present with intricate clinical manifestations and pathological features, often rendering them challenging to diagnose and impacting patients' quality of life. Despite this, they have yet to be fully recognized.

METHODS

This article presents a literature review of published original articles and review articles concerning paraneoplastic rheumatic syndromes and rheumatic diseases associated with cancer treatment. We conducted a comprehensive literature search in PubMed, Web of Science and Google Scholar databases, excluding duplicated and irrelevant studies. In cases of duplicated research, we selected articles with higher impact factors for the review.

RESULTS

This review focuses on the clinical features, diagnosis, and treatment of paraneoplastic rheumatic diseases, as well as the pathogenesis of these diseases. Additionally, we summarize the autoimmune rheumatic diseases associated with cancer treatment. Ultimately, the goal of this review is to enhance recognition and improve the management of autoimmune rheumatic diseases related to tumors.

Concomitant Use of Steroids and Immunotherapy in a Patient With Paraneoplastic Dermatomyositis and Gastroesophageal Adenocarcinoma

Idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of autoimmune pathologies often associated with occult malignancies. Glucocorticoids (GCs) represent the initial therapy to control symptoms and avoid complications. Immune checkpoint inhibitors (ICIs) have shifted the paradigm of cancer treatment. Nivolumab has become the first-line therapy in combination with chemotherapy for untreated, unresectable, non-HER-2-positive advanced gastroesophageal adenocarcinoma. The use of ICIs increases the risk of immune-related adverse events (irAEs), especially in patients with autoimmune diseases, and patients receiving steroids or immunosuppressants might be associated with poorer immunotherapy efficacy. We describe the case of a 49-year-old male who was diagnosed with paraneoplastic dermatomyositis (PDM) and gastroesophageal adenocarcinoma. He was started on prednisone taper, and concomitantly, he was started on chemotherapy with fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT), with administration of pegfilgrastim and dexamethasone during each cycle. Additionally, he was started on nivolumab. His course was complicated by worsening episodes of myopathies due to the immunotherapy, requiring adjustments to the prednisone taper. A positron emission tomography (PET) scan and repeat endoscopic ultrasonography with biopsy eight months after therapy initiation showed no major evidence of disease compared to prior. In our case, we exemplified the importance of multidisciplinary management for dosing and tapering of GCs and timing of ICI initiation, and we described the successful response to nivolumab in a patient with autoimmune disease concurrently receiving GCs.

Immune checkpoint inhibitors induced side effects of the peripheral nervous system

PURPOSE OF REVIEW

This review highlights recent knowledge on the diagnosis and treatment of immune checkpoint inhibitor-induced neurological side effects (irNAE) focussing on the neuromuscular system.

RECENT FINDINGS

irNAEs mainly resemble sporadic neuromuscular autoimmune diseases and paraneoplastic neurological syndromes. However, neurological symptoms may be unspecific (muscle weakness, fatigue) in the oncological setting and carry the risk of misdiagnosis and delayed therapeutic intervention. The role of disease-specific neuromuscular autoantibodies in the diagnosis is controversial as preexisting autoantibodies may otherwise be present before immune checkpoint inhibitor (ICI) treatment without clinical symptoms and may not develop in case of irNAE manifestation. A new necrotising form of myositis (irMyositis) has been described presenting with facial weakness and ptosis mimicking myasthenia gravis. It comes along with a high rate of severe myocarditis accounting for a triad overlap syndrome (myasthenia/myositis/myocarditis). The role of modern biologicals in the treatment of irNAEs has to be determined.

SUMMARY

irNAEs are rare but carry the risk of permanent morbidity and mortality. Early suspicion and diagnosis are key to prevent neurological sequelae. Beyond interruption of ICI administration, treatment corresponds to sporadic autoimmune diseases. The myasthenia/myositis/myocarditis overlap syndrome deserves special attention as it carries the highest risk of mortality. The role of neurotoxic pretreatment regimens, preexisting subclinical neurological autoimmune diseases and the risk of ICI-re-challenge after irNAEs has to be further investigated.

Role of Biomarkers in the Management of Immune-Checkpoint Inhibitor-Related Myocarditis

PURPOSE OF REVIEW

Immune checkpoint inhibitor (ICI)-related myocarditis poses a major clinical challenge given its non-specific presentation, rapid progression, and high mortality rate. Here, we review the role of blood-based biomarkers in the clinical management of patients with ICI-related myocarditis.

RECENT FINDINGS

Myocardial injury, its unique pattern, and the co-occurrence with myositis are defining features of ICI-related myocarditis. Non-cardiac biomarkers, specifically creatinine phosphokinase, precedes the symptomatic presentation and is highly sensitive for diagnosing ICI-related myocarditis, making them useful screening biomarkers. Combined elevations in cardiac troponins and non-cardiac biomarkers improve the confidence of an ICI myocarditis diagnosis. High troponin and creatinine phosphokinase levels are strongly associated with severe outcomes. We propose biomarker-based algorithms for the monitoring and diagnosis of ICI-related myocarditis. Biomarkers, such as cardiac troponins and creatine phosphokinase, can be used in combination in the monitoring, diagnosis, and prognostication of patients with ICI-related myocarditis.

Rheumatic complications of checkpoint inhibitors: Lessons from autoimmunity

Immune checkpoint inhibitors are now an established treatment in the management of a range of cancers. Their success means that their use is likely to increase in future in terms of the numbers of patients treated, the indications and the range of immune checkpoints targeted. They function by counteracting immune evasion by the tumor but, as a consequence, can breach self-tolerance at other sites leading to a range of immune-related adverse events. Included among these complications are a range of rheumatologic complications, including inflammatory arthritis and keratoconjunctivitis sicca. These superficially resemble immune-mediated rheumatic diseases (IMRDs) such as rheumatoid arthritis and Sjogren's disease but preliminary studies suggest they are clinically and immunologically distinct entities. However, there appear to be common processes that predispose to the development of both that may inform preventative interventions and predictive tools. Both groups of conditions highlight the centrality of immune checkpoints in controlling tolerance and how it can be restored. Here we will discuss some of these commonalities and differences between rheumatic irAEs and IMRDs.

Cardiomuscular Biomarkers in the Diagnosis and Prognostication of Immune Checkpoint Inhibitor Myocarditis

BACKGROUND

Immune checkpoint inhibitors (ICIs) are approved for multiple cancers but can result in ICI-associated myocarditis, an infrequent but life-threatening condition. Elevations in cardiac biomarkers, specifically troponin-I (cTnI), troponin-T (cTnT), and creatine kinase (CK), are used for diagnosis. However, the association between temporal elevations of these biomarkers with disease trajectory and outcomes has not been established.

METHODS

We analyzed the diagnostic accuracy and prognostic performances of cTnI, cTnT, and CK in patients with ICI myocarditis (n=60) through 1-year follow-up in 2 cardio-oncology units (APHP Sorbonne, Paris, France and Heidelberg, Germany). A total of 1751 (1 cTnT assay type), 920 (4 cTnI assay types), and 1191 CK sampling time points were available. Major adverse cardiomyotoxic events (MACE) were defined as heart failure, ventricular arrhythmia, atrioventricular or sinus block requiring pacemaker, respiratory muscle failure requiring mechanical ventilation, and sudden cardiac death. Diagnostic performance of cTnI and cTnT was also assessed in an international ICI myocarditis registry.

RESULTS

Within 72 hours of admission, cTnT, cTnI, and CK were increased compared with upper reference limits (URLs) in 56 of 57 (98%), 37 of 42 ([88%] P=0.03 versus cTnT), and 43 of 57 ([75%] P<0.001 versus cTnT), respectively. This increased rate of positivity for cTnT (93%) versus cTnI ([64%] P<0.001) on admission was confirmed in 87 independent cases from an international registry. In the Franco-German cohort, 24 of 60 (40%) patients developed ≥1 MACE (total, 52; median time to first MACE, 5 [interquartile range, 2-16] days). The highest value of cTnT:URL within the first 72 hours of admission performed best in terms of association with MACE within 90 days (area under the curve, 0.84) than CK:URL (area under the curve, 0.70). A cTnT:URL ≥32 within 72 hours of admission was the best cut-off associated with MACE within 90 days (hazard ratio, 11.1 [95% CI, 3.2-38.0]; P<0.001), after adjustment for age and sex. cTnT was increased in all patients within 72 hours of the first MACE (23 of 23 [100%]), whereas cTnI and CK values were less than the URL in 2 of 19 (11%) and 6 of 22 (27%) of patients (P<0.001), respectively.

CONCLUSIONS

cTnT is associated with MACE and is sensitive for diagnosis and surveillance in patients with ICI myocarditis. A cTnT:URL ratio <32 within 72 hours of diagnosis is associated with a subgroup at low risk for MACE. Potential differences in diagnostic and prognostic performances between cTnT and cTnI as a function of the assays used deserve further evaluation in ICI myocarditis.

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.

Neurologic Complications of Cancer Immunotherapy

Immunotherapy has revolutionized cancer treatment over the past decade. As it is increasingly introduced into routine clinical practice, immune-related complications have become more frequent. Accurate diagnosis and treatment are essential, with the goal of reduced patient morbidity. This review aims to discuss the various clinical manifestations, diagnosis, treatments, and prognosis of neurologic complications associated with the use of immune checkpoint inhibitors, adoptive T-cell therapies, and T-cell redirecting therapies. We also outline a suggested clinical approach related to the clinical use of these agents.

Transcriptomic profiling reveals distinct subsets of immune checkpoint inhibitor induced myositis

OBJECTIVES

Inflammatory myopathy or myositis is a heterogeneous family of immune-mediated diseases including dermatomyositis (DM), antisynthetase syndrome (AS), immune-mediated necrotising myopathy (IMNM) and inclusion body myositis (IBM). Immune checkpoint inhibitors (ICIs) can also cause myositis (ICI-myositis). This study was designed to define gene expression patterns in muscle biopsies from patients with ICI-myositis.

METHODS

Bulk RNA sequencing was performed on 200 muscle biopsies (35 ICI-myositis, 44 DM, 18 AS, 54 IMNM, 16 IBM and 33 normal muscle biopsies) and single nuclei RNA sequencing was performed on 22 muscle biopsies (seven ICI-myositis, four DM, three AS, six IMNM and two IBM).

RESULTS

Unsupervised clustering defined three distinct transcriptomic subsets of ICI-myositis: ICI-DM, ICI-MYO1 and ICI-MYO2. ICI-DM included patients with DM and anti-TIF1γ autoantibodies who, like DM patients, overexpressed type 1 interferon-inducible genes. ICI-MYO1 patients had highly inflammatory muscle biopsies and included all patients that developed coexisting myocarditis. ICI-MYO2 was composed of patients with predominant necrotising pathology and low levels of muscle inflammation. The type 2 interferon pathway was activated both in ICI-DM and ICI-MYO1. Unlike the other types of myositis, all three subsets of ICI-myositis patients overexpressed genes involved in the IL6 pathway.

CONCLUSIONS

We identified three distinct types of ICI-myositis based on transcriptomic analyses. The IL6 pathway was overexpressed in all groups, the type I interferon pathway activation was specific for ICI-DM, the type 2 IFN pathway was overexpressed in both ICI-DM and ICI-MYO1 and only ICI-MYO1 patients developed myocarditis.

Neurological outcomes in immune checkpoint inhibitor-related neurotoxicity

While the spectrum of neurological immune checkpoint inhibitor-related adverse events is expanding, patients' outcomes are not well documented. This study aimed to assess outcomes of neurological immune-related adverse events and to identify prognostic factors. All patients experiencing grade ≥2 neurological immune-related adverse events identified at two clinical networks (French Reference Center for Paraneoplastic Neurological Syndromes, Lyon; and OncoNeuroTox, Paris) over five years were included. Modified Rankin scores were assessed at onset, 6, 12, 18 months, and last visit. A multi-state Markov model was used to estimate the transition rates between minor disability (mRS <3), severe disability (mRS 3-5), and death (mRS 6), over the study period. The state-to-state transition rates were estimated using maximum likelihood and variables were introduced into the different transitions to study their effects. A total of 147 patients were included out of 205 patients with a suspicion of neurological immune-related adverse events. The median age was 65 years (range 20-87) and 87/147 patients (59.2%) were male. Neurological immune-related adverse events involved the peripheral nervous system in 87/147 patients (59.2%), the central nervous system in 51/147 (34.7%), and both systems in 9/147 (6.1%). Paraneoplastic-like syndromes were observed in 30/147 patients (20.4%). Cancers included lung cancers (36.1%), melanoma (30.6%), urological cancers (15.6%), and others (17.8%). Patients were treated with programmed cell death protein (ligan) 1 (PD(L)1) inhibitors (70.1%), CTLA4 inhibitors (3.4%) or both (25.9%). Severe disability was reported in 108/144 patients (75.0%) at onset and in 33/146 patients (22.6%) at last visit (median follow-up duration: 12 months, range 0.5-50); 48/147 (32.7%) patients died, from cancer progression (17/48, 35.4%), neurological toxicity (15/48, 31.2%), other causes (10/48, 20.8%) or unknown causes (6/48, 12.5%). The rate of transition from severe to minor disability independently increased with melanoma [compared to lung cancer, hazard ratio = 3.26, 95%CI (1.27; 8.41)] and myositis/neuromuscular junction disorders [hazard ratio = 8.26, 95%CI (2.90; 23.58)], and decreased with older age [hazard ratio = 0.68, 95%CI (0.47; 0.99)] and paraneoplastic-like syndromes [hazard ratio = 0.29, 95%CI (0.09; 0.98)]. In patients with neurological immune-related adverse events, myositis/neuromuscular junction disorders and melanoma increase the transition rate from severe to minor disability, while older age and paraneoplastic-like syndromes result in poorer neurological outcomes; future studies are needed to optimize the management of such patients.

Drug therapy for myocarditis induced by immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs), including cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death 1 (PD-1), and its ligand 1 (PD-L1), have improved the survival in multiple types of cancers; however, ICIs may cause cardiovascular toxicity. Although rare, ICI-mediated cardiotoxicity is an extremely serious complication with a relatively high mortality. In this review, we discuss the underlying mechanism and clinical manifestations of cardiovascular toxicity induced by ICIs. According to previous studies, multiple signaling pathways are involved in myocarditis induced by ICIs. Further, we summarize the clinical trials of drugs for the treatment of ICI-associated myocarditis. Although these drugs have shown the beneficial effects of alleviating cardiac function and reducing mortality rates, their efficacy is not optimal. Finally, we discuss the therapeutic potential of some novel compounds as well as the underlying mechanisms of their action.

Rheumatologic immune checkpoint inhibitor-related adverse events

PURPOSE OF REVIEW

Immune check point inhibitors (ICIs) are a unique class of cancer treatments that harness the body's innate antitumor response. Although these medications have transformed oncology care, they also lead to generalized immune activation that can result in toxicities across a spectrum of organ systems called immune-related adverse events. This article reviews the most common rheumatologic immune-related adverse events and their management.

RECENT FINDINGS

Inflammatory arthritis, polymyalgia rheumatic, sicca symptoms, systemic sclerosis, myositis, and vasculitis have all been reported as ICI adverse events. Treatment includes nonsteroidal anti-inflammatory drugs, glucocorticoids, traditional DMARDs, and biologics.

SUMMARY

Rheumatologists have an important role in the management of patients with rheumatologic immune-related adverse events. Working with our oncology colleagues, we can help manage rheumatologic immune-related adverse events while optimally preserving ICI's antitumor effects.