Diagnosis and Management of Immune Checkpoint Inhibitor-Associated Neurologic Toxicity: Illustrative Case and Review of the Literature

Managing suspected myasthenia gravis and myositis induced by pembrolizumab in a Jehovah's Witness sarcoma patient

INTRODUCTION

Immune checkpoint inhibitors (ICIs) can cause a spectrum of adverse events known as immune-related adverse events (irAEs) that resemble autoimmune responses. Immune-mediated myasthenia gravis (MG) is a rare and serious neurologic adverse event that has been associated with ICIs requiring prompt treatment. In the Jehovah's Witness population, typical management of these adverse events may not be options, and alternative treatment choices would be needed.

CASE REPORT

73-year-old Jehovah's Witness patient with high-grade undifferentiated pleiomorphic sarcoma who developed immune-mediated MG approximately 4 weeks after initiation of pembrolizumab. On the day of admission, the patient presented with a three-day history of worsening ptosis, right greater than left. He was later found to be seronegative for MG.

MANAGEMENT AND OUTCOME

The patient required therapy with pyridostigmine, steroids, and agreed to plasma exchange (PLEX) prior to discharge. He achieved near resolution of his neurologic symptoms, and pembrolizumab was discontinued. He later underwent radical resection of the left thigh soft tissue sarcoma and superficial inguinal lymph node dissection. He is now on active surveillance.

DISCUSSION

While neurologic adverse events typically present 6 weeks after initiation of ICIs, MG has been reported occurring as early as 4 weeks after initiation. This rare and serious adverse event requires prompt treatment, and clinicians need to be aware of the alternative treatment options in this unique patient population. Early conversations regarding blood products and factions must be had to develop a treatment plan in accordance with the patient's personal decisions.

Anti-PD-1 cancer immunotherapy induces central nervous system immune-related adverse events by microglia activation

Cancer treatment with anti-PD-1 immunotherapy can cause central nervous system immune-related adverse events (CNS-irAEs). The role of microglia in anti-PD-1 immunotherapy-induced CNS-irAEs is unclear. We found that anti-PD-1 treatment of mice caused morphological signs of activation and major histocompatibility complex (MHC) class II up-regulation on microglia. Functionally, anti-PD-1 treatment induced neurocognitive deficits in mice, independent of T cells, B cells, and natural killer cells. Instead, we found that microglia mediated these CNS-irAEs. Single-cell RNA sequencing revealed major transcriptional changes in microglia upon anti-PD-1 treatment. The anti-PD-1 effects were mediated by anti-PD-1 antibodies interacting directly with microglia and were not secondary to peripheral T cell activation. Using a proteomics approach, we identified spleen tyrosine kinase (Syk) as a potential target in activated microglia upon anti-PD-1 treatment. Syk inhibition reduced microglia activation and improved neurocognitive function without impairing anti-melanoma effects. Moreover, we analyzed CNS tissue from a patient cohort that had received anti-PD-1 treatment. Imaging mass cytometry revealed that anti-PD-1 treatment of patients was associated with increased surface marker expression indicative of microglia activation. In summary, we identified a disease-promoting role for microglia in CNS-irAEs driven by Syk and provide an inhibitor-based approach to interfere with this complication after anti-PD-1 immunotherapy.

Immune checkpoint inhibitors and neurotoxicity: a focus on diagnosis and management for a multidisciplinary approach

INTRODUCTION

Although immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, the consequential over activation of the immune system is often complicated by adverse events that can affect several organs and systems, including the nervous system. The precise pathophysiology underlying neurological irAEs (n-irAEs) is not completely known. Around 3.8% of patients receiving anti-CTLA-4 agents, 6.1% of patients receiving anti-PD-1/PD-L1, and 12% of patients receiving combination therapies have n-irAEs. Most n-irAEs are low-grade, while severe toxicities have rarely been reported. in this article, we performed an updated literature search on immuno-related neurotoxicity on main medical research database, from February 2017 to December 2023.

AREAS COVERED

We have also compared the latest national and international guidelines on n-irAEs management with each other in order to better define patient management.

EXPERT OPINION

A multidisciplinary approach appears necessary in the management of oncological patients during immunotherapy. Therefore, in order to better manage these toxicities, we believe that it is essential to collaborate with neurologists specialized in the diagnosis and treatment of n-irAEs, and that a global neurological assessment, both central and peripheral, is necessary before starting immunotherapy, with regular reassessment during treatment.

Update on Neuro-ophthalmic Manifestations of Immune Checkpoint Inhibitors

PURPOSE OF REVIEW

Immune checkpoint inhibitor (ICI) use has been on the rise for treatment of many different malignancies. Subsequently, more has been learned about immune-related adverse events (irAEs) that occur up to 12 months after treatment. This review summarizes the latest findings and management of neuro-ophthalmic associated irAEs.

RECENT FINDINGS

irAEs can affect the afferent and efferent neuro-ophthalmic pathways, thereby targeting central and peripheral nervous systems. As more cases are being reported, it is becoming apparent that neuro-ophthalmic irAEs often present with atypical features when compared to their spontaneous autoimmune counterparts. These neuro-ophthalmic presentations can also be signs of a more extensive inflammatory process that spans other organ systems, such as myopathies, endocrinopathies, and paraneoplastic syndromes. Awareness of neuro-ophthalmic irAEs and their atypical presentations can lead to early detection, termination of ICI treatment, and immunosuppressant therapy initiation.

[A case of Stiff-person syndrome with muscle tonicity of the extremities and neck after use of Dulvalumab for lung adenocarcinoma]

A 74-year-old woman taking dulvalumab for lung adenocarcinoma developed muscle tonicity in the extremities and trunk. Painful paroxysmal muscle spasms with profuse sweating were frequently observed, and surface electromyography showed simultaneous contraction of the active and antagonist muscles. Blood tests were strongly positive for anti-amphiphysin antibodies, and stiff-person syndrome (SPS) was diagnosed. Intravenous immunoglobulin therapy and clonazepam were initiated, and the paroxysmal painful muscle spasms disappeared. As the primary tumor was under control, and the onset occurred approximately six weeks after the resumption of immune checkpoint inhibitors, we considered SPS to be an immune-related adverse event. Although extremely rare, it should be considered a neuromuscular disease that can occur in association with immune checkpoint inhibitors.

Achilles' Heel of currently approved immune checkpoint inhibitors: immune related adverse events

Immunotherapy has revolutionized the cancer treatment landscape by opening up novel avenues for intervention. As the use of immune checkpoint inhibitors (ICIs) has exponentially increased, so have immune-related adverse events (irAEs). The mechanism of irAEs may involve the direct damage caused by monoclonal antibodies and a sequence of immune responses triggered by T cell activation. Common side effects include dermatologic toxicity, endocrine toxicity, gastrointestinal toxicity, and hepatic toxicity. While relatively rare, neurotoxicity, cardiotoxicity, and pulmonary toxicity can be fatal. These toxicities pose a clinical dilemma regarding treatment discontinuation since they can result in severe complications and necessitate frequent hospitalization. Vigilant monitoring of irAEs is vital in clinical practice, and the principal therapeutic strategy entails the administration of oral or intravenous glucocorticoids (GSCs). It may be necessary to temporarily or permanently discontinue the use of ICIs in severe cases. Given that irAEs can impact multiple organs and require diverse treatment approaches, the involvement of a multidisciplinary team of experts is imperative. This review aims to comprehensively examine the pathogenesis, clinical manifestations, incidence, and treatment options for various irAEs.

Immune checkpoint monoclonal antibody-related adverse effects in neuro-ophthalmology

Immunotherapy has renovated the field of oncology. Usually, cancer is treated by surgery, chemotherapy, and radiation. Immunotherapy is a promising treatment that harnesses the patient's own immune system to target cancer. Immune checkpoint inhibitors (ICIs) have proven to be a promising treatment avenue for managing cancer; however, their use had been associated with a unique spectrum of adverse side effects called immune-related adverse events (irAEs). As ICIs become increasingly relevant in cancer management, it is crucial to address these irAEs affecting various systems in the body, including the skin, liver, gastrointestinal tract, endocrine system, and the eye. Ocular toxicity and sight-threatening events are among the reported irAEs, impacting diverse ocular tissues. The most commonly reported ocular irAEs (OirAEs) are blurred vision, conjunctivitis, ocular surface disease uveitis, scleritis, and retinopathy. Nevertheless, the frequency and severity of these OirAEs can vary, even within the same class of ICIs. Thus, OirAEs can significantly impact the quality of life and patient compliance. Therefore, we aim to comprehensively analyze uncommon and severe ICI-related OirAEs associated with lung cancer by providing a comprehensive and updated review of immune checkpoint monoclonal antibody-related adverse effects in neuro-ophthalmology irAEs. Through a review of the relevant literature, we intend to illustrate the epidemiology, clinical characteristics, contributory factors, diagnosis, and management of ICI-associated ocular side effects. We will also discuss guidelines and best practice strategies for the prevention, monitoring, and management of these OirAEs.

Incidence and Outcome of Neurologic Immune-Related Adverse Events Associated With Immune Checkpoint Inhibitors in Patients With Melanoma

BACKGROUND AND OBJECTIVES

Neurologic immune-related adverse events (n-irAEs) reportedly occur in up to 8% of patients treated with immune checkpoint inhibitors (ICIs) of all age groups. We investigated the association between age and n-irAEs in patients treated with ICIs and examined the effect of n-irAEs on survival outcomes in a large cohort of patients with melanoma.

METHODS

We conducted a retrospective analysis of patients with advanced melanoma treated with ICIs at Ella Institute for Immuno-oncology and Melanoma between January 1, 2015, and April 20, 2022. The outcomes of interest were defined as the investigation of age-related frequency and severity of n-irAEs, the need for ICI interruption, the treatment required for n-irAE management, the safety of ICI reintroduction, and n-irAE's effect on survival.

RESULTS

ICI was administered to 937 patients. At least one irAE occurred in 73.5% (n = 689) of them. Among the study population, 8% (n = 76) developed a n-irAE, with a median age of 66 years in female and 68 years in male patients at onset. The median follow-up after n-irAE was 1,147 days (IQR: 1,091.5 range: 3,938). Fewer irAEs occurred in patients older than 70 years (median: 3 events, p = 0.04, CI 2.5-4.7) while specifically colitis and pneumonitis were more common in the 18-60 age group (p = 0.03, 95% CI 0.8-0.38, p = 0.009, 95% CI 0.06-0.2). Grade ≥ 3 toxicity was seen in 35.5% of patients across age groups. The median time from ICI administration to n-irAE development was 48 days across age groups. Common n-irAE phenotypes were myositis (44.7%), encephalitis (10.5%), and neuropathy (10.5%). N-irAE required hospitalization in 40% of patients and steroids treatment in 46% with a median of 4 days from n-irAE diagnosis to steroids treatment initiation. Nine patients needed second-line immunosuppressive treatment. Rechallenge did not cause additional n-irAE in 71% of patients. Developing n-irAE (HR = 0.4, 95% CI 0.32-0.77) or any irAE (HR = 0.7195% CI 0.56-0.88) was associated with longer survival.

DISCUSSION

N-irAEs are a relatively common complication of ICIs (8% of our cohort). Older age was not associated with its development or severity, in contrast with non-n-irAEs which occurred less frequently in the elderly population. Rechallenge did not result in life-threatening AEs. Development of any irAEs was associated with longer survival; this association was stronger with n-irAEs.

Neurological adverse events related to immune-checkpoint inhibitors in Spain: a retrospective cohort study

BACKGROUND

Neurological immune-related adverse events associated with immune checkpoint inhibitors can have several clinical manifestations, but the syndromes and prognostic factors are still not well known. We aimed to characterise and group the clinical features, with a special focus in patients presenting with encephalopathy, and to identify predictors of response to therapy and survival.

METHODS

This retrospective observational study included patients with neurological immune-related adverse events from 20 hospitals in Spain whose clinical information, serum samples, and CSF samples were studied at Hospital Clinic de Barcelona, Barcelona, Spain. Patients with pre-existing paraneoplastic syndromes or evidence of alternative causes for their neurological symptoms were excluded. We reviewed the clinical information, classified their clinical features, and determined the presence of neural antibodies. Neurological status was assessed by the treating physician one month after adverse event onset (as improvement vs no improvement) and at the last evaluation (complete recovery or modified Rankin Scale score decrease of at least 2 points, indicating good outcome, vs all other modified Rankin Scale scores, indicating poor outcome); if the participant had died, the date and cause of death were recorded. We used Fisher's exact tests and Mann-Whitney U tests to analyse clinical features, and multivariable logistic regression to analyse prognostic factors.

FINDINGS

From Jan 1, 2018, until Feb 1, 2023, 83 patients with suspected neurological immune-related adverse events after use of immune checkpoint inhibitors were identified, of whom 64 patients were included. These patients had a median age of 67 years (IQR 59-74); 42 (66%) were male and 22 (34%) were female. The predominant tumours were lung cancer (30 [47%] patients), melanoma (13 [21%] patients), and renal cell carcinoma (seven [11%] patients). Neural antibodies were detected in 14 (22%) patients; 52 (81%) patients had CNS involvement and 12 (19%) had peripheral nervous system involvement. Encephalopathy occurred in 45 (70%) patients, 12 (27%) of whom had antibodies or well defined syndromes consistent with definite paraneoplastic or autoimmune encephalitis, 24 (53%) of whom had encephalitis without antibodies or clinical features characteristic of a defined syndrome, and nine (20%) of whom had encephalopathy without antibodies or inflammatory changes in CSF or brain MRI. Nine (14%) of 64 patients had combined myasthenia and myositis, five of them with myocarditis. Even though 58 (91%) of 64 patients received steroids and 31 (48%) of 64 received additional therapies, 18 (28%) did not improve during the first month after adverse event onset, and 11 of these 18 people died. At the last follow-up for the 53 remaining patients (median 6 months, IQR 3-13), 20 (38%) had a poor outcome (16 deaths, one related to a neurological immune-related adverse event). Mortality risk was increased in patients with lung cancer (vs those with other cancers: HR 2·5, 95% CI 1·1-6·0) and in patients with encephalopathy without evidence of CNS inflammation or combined myocarditis, myasthenia, and myositis (vs those with the remaining syndromes: HR 5·0, 1·4-17·8 and HR 6·6, 1·4-31·0, respectively).

INTERPRETATION

Most neurological immune-related adverse events involved the CNS and were antibody negative. The presence of myocarditis, myasthenia, and myositis, of encephalopathy without inflammatory changes, or of lung cancer were independent predictors of death. Most deaths occurred during the first month of symptom onset. If our findings are replicated in additional cohorts, they could confirm that these patients need early and intensive treatment.

FUNDING

The Instituto de Salud Carlos III and the European Union.

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.

The Immune System's Echo: The Phenomenon of Delayed Neurological Immune-Related Adverse Events (NirAEs) in Adjuvant Immunotherapy

The use of immune checkpoint inhibitors (ICIs) in early-stage settings has shown promise but can lead to chronic immune-related toxicities known as delayed immune-related adverse events (DIREs). These events, occurring after immunotherapy cessation, can affect various organ systems. Fatal immune-related adverse events (irAEs) are relatively rare but significant. Diagnostic challenges exist in distinguishing DIREs from disease sequelae. Efforts are needed to develop evidence-based strategies for managing DIREs as long-term survival with ICIs becomes possible. This case study highlights delayed neurological immune-related adverse events (NirAEs) encountered during pembrolizumab treatment, emphasizing the need for accurate diagnosis and prompt management. Reporting practices in immunotherapy trials hinder accurate assessment of DIREs. Close monitoring, accurate diagnosis, and timely corticosteroid administration are vital for effective DIRE management.

Severe neuromuscular immune-related adverse events of immune checkpoint inhibitors at national cancer center in Korea

PURPOSE

Neuromuscular immune-related adverse events (irAEs) associated with immune checkpoint inhibitors (ICIs) have been increasingly recognized as a consequence of expanding use of ICIs in advanced cancers. We aimed to evaluate the frequency, phenotypes, rescue treatment, and clinical outcomes of severe neuromuscular irAEs of ICIs at National Cancer Center (NCC), Korea.

MATERIALS AND METHODS

Consecutive patients with newly developed severe neuromuscular irAEs (common terminology criteria for adverse events grade 3 or greater) after ICI treatment at NCC in Korea between December 2018 and April 2022 were included by searching neuromuscular diagnostic codes in electronic medical records and/or reviewing neurological consultation documentations.

RESULTS

Of the 1,503 ICI-treated patients, nine (0.6%) experienced severe neuromuscular irAEs; five with pembrolizumab and four with atezolizumab. The patients included five women and four men; their median age at onset was 59 years. The irAEs included Guillain-Barre syndrome (n = 5) and myasthenia gravis (MG) crisis with myositis (n = 4), and developed after a median of one (range 1-5) ICI cycle. The median modified Rankin score (mRS) was 4 (range 3-5) at the nadir. ICIs were discontinued in all patients, and rescue immunotherapy included corticosteroids (n = 9), intravenous immunoglobulin (n = 7), and plasmapheresis (n = 2). Eight patients showed improvements, with a median mRS of 3 (range 1-4); however, one patient (who had MG crisis with myocarditis) died.

CONCLUSIONS

In this real-world monocentric study, ICI-induced neuromuscular irAEs were rare but potentially devastating; thus, physicians should remain vigilant to enable prompt recognition and management of irAEs.

Shedding light on the side effects of immunotherapies used for leukemia: an updated review of the literature

INTRODUCTION

Leukemia is an abnormal clonal development of leukemic cells originating from the bone marrow, which is widely known for its significant prevalence and mortality rate. Chemotherapy, surgery, radiation, and combination therapies have been its routine therapeutic methods; however, the advent of cancer immunotherapy is known as revolutionary for its higher efficacy and lesser toxicity.

AREAS COVERED

Immunotherapy boosts the body's immune system by using components from other living organisms. Although immunotherapy seems to be safer than chemotherapy, many studies have noticed different immune-related side effects in various body systems (e.g. cardiovascular, neurologic) which we have reviewed in this investigation as the main goal. We tried to describe immunotherapy-related side effects in human body systems in detail.

EXPERT OPINION

Being aware of these side effects leads to better clinical decision-making for each individual, and a one-step-ahead management in case of occurrence. We also briefly discussed the role of immunotherapy in treating leukemia as one of the most prevalent cancers in children and tried to emphasize that it is crucial to monitor adverse events as they may remain obscure until adolescence.

Immune checkpoint inhibitor induced neurocognitive deficits in patients

This scientific commentary refers to 'Neurological outcomes in immune checkpoint inhibitor-related neurotoxicity', by Farina et al. (https://doi.org/10.1093/braincomms/fcad169).

Neurologic Complications of Cancer Treatment

OBJECTIVE

Advances in cancer treatment have led to extended survival and increased risk of neurologic complications in an aging population. This review summarizes potential neurologic complications in patients who have undergone treatment for neurologic and systemic malignancies.

LATEST DEVELOPMENTS

Radiation and cytotoxic chemotherapy along with other targeted therapies continue to be the mainstay of cancer treatment. These advances in cancer care have led to improved outcomes and increased the need to understand the spectrum of neurologic complications that may arise from treatment. While radiation and older therapies including cytotoxic chemotherapies have side effect profiles that are widely known and well understood, this article serves as a review of the more commonly associated neurologic complications of both traditional and newer treatments being offered to this patient population.

ESSENTIAL POINTS

Neurotoxicity is a common complication of cancer-directed treatment. In general, neurologic complications of radiation therapy are more common in central nervous system malignancies, and neurologic complications of chemotherapy are more common in non-neurologic malignancies. Attempts at prevention, early detection, and intervention remain paramount in the reduction of neurologic morbidity.

A Brain, A Heart, and the Courage: Balancing Benefit and Toxicity of Immunotherapy in Melanoma

The overall survival of advanced melanoma has improved dramatically. Immunotherapies, specifically checkpoint inhibitors, have played a large role in this improvement. These agents have also shown benefit in the adjuvant setting, are approved for treatment of resected stage II, III, and IV melanoma, and play an evolving role in the neoadjuvant setting. Although generally well tolerated, immune-related adverse events occur and can be severe. Here we focus on some severe and potentially long term toxicities, including cardiovascular and neurologic toxicities. Our understanding of the acute and long-term toxicities of immune checkpoint inhibitors continues to evolve. Oncologists must continue to balance cancer risk and treatment-related toxicities.

Demyelinating polyneuropathy combined with brachial plexopathy after nivolumab therapy for hodgkin lymphoma: a case report

BACKGROUND

Nivolumab is an immune checkpoint inhibitor that targets the programmed cell death-1 protein and is effective in treating advanced cancer. However, it is also associated with various immune-related neurological complications, including myasthenia gravis, Guillain-Barré syndrome, and demyelinating polyneuropathy. These complications can easily mimic other neurological diseases and have greatly varying therapeutic approaches depending on the underlying pathophysiology.

CASE PRESENTATION

Here, we report a case of nivolumab-induced demyelinating peripheral polyneuropathy involving the brachial plexus in a patient with Hodgkin lymphoma. Approximately 7 months after nivolumab treatment, the patient experienced muscle weakness with a tightness and tingling sensation in the right forearm. Electrodiagnostic studies showed features of demyelinating peripheral neuropathy with right brachial plexopathy. Magnetic resonance imaging revealed thickening with a diffuse enhancement of both brachial plexuses. The patient was eventually diagnosed with nivolumab-induced demyelinating polyneuropathy involving the brachial plexus. Oral steroid therapy improved motor weakness and sensory abnormalities without aggravation.

CONCLUSION

Our study indicates the possibility of nivolumab-induced neuropathies in cases involving muscle weakness with sensory abnormalities of the upper extremity following nivolumab administration in patients with advanced cancer. Comprehensive electrodiagnostic studies and magnetic resonance imaging are helpful in the differential diagnosis of other neurological diseases. Appropriate diagnostic and therapeutic approaches may prevent further neurological deterioration.

Do peripheral neuropathies differ among immune checkpoint inhibitors? Reports from the European post-marketing surveillance database in the past 10 years

Although the immunotherapy advent has revolutionized cancer treatment, it, unfortunately, does not spare cancer patients from possible immune-related adverse events (irAEs), which can also involve the peripheral nervous system. Immune checkpoint inhibitors (ICIs), blocking cytotoxic T-lymphocyteassociated protein 4 (CTLA-4), programmed cell death protein 1 (PD-1), or programmed cell death ligand 1 (PD-L1), can induce an immune imbalance and cause different peripheral neuropathies (PNs). Considering the wide range of PNs and their high impact on the safety and quality of life for cancer patients and the availability of large post-marketing surveillance databases, we chose to analyze the characteristics of ICI-related PNs reported as suspected drug reactions from 2010 to 2020 in the European real-world context. We analyzed data collected in the European pharmacovigilance database, Eudravigilance, and conducted a systematic and disproportionality analysis. In our study, we found 735 reports describing 766 PNs occurred in patients treated with ICIs. These PNs included Guillain-Barré syndrome, Miller-Fisher syndrome, neuritis, and chronic inflammatory demyelinating polyradiculoneuropathy. These ADRs were often serious, resulting in patient disability or hospitalization. Moreover, our disproportionality analysis revealed an increased reporting frequency of PNs with tezolizumab compared to other ICIs. Guillain-Barré syndrome is a notable potential PN related to ICIs, as it is associated with a significant impact on patient safety and has had unfavorable outcomes, including a fatal one. Continued monitoring of the safety profile of ICIs in real-life settings is necessary, especially considering the increased frequency of PNs associated with atezolizumab compared with other ICIs.

Stuttering as a signal of encephalopathy associated with toripalimab in a pancreatic ductal adenocarcinoma patient: a case report

BACKGROUND

Immune checkpoint inhibitor (ICI) combined with chemotherapy has exhibited promising results in small sample studies of pancreatic cancer patients. The efficacy of toripalimab, a programmed cell death protein 1 (PD-1) monoclonal antibody has been explored in the previous studies and it was established that immune-related adverse events (irAEs) associated with administration of this drug deserve proper attention and adequate management.

CASE PRESENTATION

A 43-year-old female patient with advanced pancreatic ductal adenocarcinoma (PDAC) was treated with toripalimab in combination with gemcitabine and nab-paclitaxel (T-GA) as the first-line treatment. She developed immune-related encephalopathy with stuttering as the main clinical symptom and Magnetic resonance imaging (MRI) showed multiple cerebral white matter demyelination changes, concomitant with asymptomatic cardiac enzyme elevation and hypothyroidism. The symptoms resolved after the discontinuation of toripalimab and corticosteroid treatment.

CONCLUSIONS

Stuttering might be an early sign of neurotoxicity which can be easily neglected during the treatment. These findings provide guidance for the identification of these rare and occult neurological irAEs (n-irAEs) in the clinical practice.

Evaluation and management of acute high-grade immunotherapy-related neurotoxicity

Immune checkpoint inhibitor monoclonal antibodies allow the host's immune system to attack tumors, which has revolutionized cancer care over the last decade. As the use of immune checkpoint inhibitors has expanded, so have autoimmune-like complications known as immune-related adverse events. These include the infrequent but increasingly more common, potentially deadly neurological immune related adverse events. When feeling acutely ill, patients will often seek care not from their oncologist but from their family physician, clinics, emergency, and urgent care sites, or other available providers. Thus, while assessing acutely ill cancer patients who are experiencing neurological symptoms, non-oncologists should be prepared to recognize, diagnose, and treat neurological immune related adverse events in addition to more familiar conditions. This narrative review is designed to update acute care clinicians on current knowledge and to present a symptom-based framework for evaluating and treating neurological immune related adverse events based on the leading immunotoxicity organizations' latest recommendations.

Monocyte chemoattractant protein 1 as a potential biomarker for immune checkpoint inhibitor-associated neurotoxicity

BACKGROUND

Oncological patients can benefit substantially from treatment with immune checkpoint inhibitors (ICI). However, there is a growing awareness of immune-related adverse events (irAE). Especially ICI-mediated neurological adverse events (nAE(+)), are tough to diagnose and biomarkers to identify patients at risk are missing.

METHODS

A prospective register with prespecified examinations was established for ICI treated patients in December 2019. At the time of data cut-off, 110 patients were enrolled and completed the clinical protocol. Herein, cytokines and serum neurofilament light chain (sNFL) from 21 patients were analyzed.

RESULTS

nAE of any grade were observed in 31% of the patients (n = 34/110). In nAE(+) patients a significant increase in sNFL concentrations over time was observed. Patients with higher-grade nAE had significantly elevated serum-concentrations of monocyte chemoattractant protein 1 (MCP-1) and brain-derived neurotrophic factor (BDNF) at baseline compared to individuals without any nAE (p < 0.01 and p < 0.05).

CONCLUSION

Here, we identified nAE to occur more frequently than previously reported. Increase of sNFL during nAE confirms the clinical diagnosis of neurotoxicity and might be a suitable marker for neuronal damage associated with ICI therapy. Furthermore, MCP-1 and BDNF are potentially the first clinical-class nAE predictors for patients under ICI therapy.

Checkpoint Inhibitor Immune-Related Adverse Events: A Multimodality Pictorial Review

Cancer immunotherapies are drugs that modulate the body's own immune system as an anticancer strategy. Checkpoint inhibitor immunotherapies interfere with cell surface binding proteins that function to promote self-recognition and tolerance, ultimately leading to upregulation of the immune response. Given the striking success of these agents in early trials in melanoma and lung cancer, they have now been studied in many types of cancer and have become a pillar of anticancer therapy for many tumor types. However, abundant upregulation results in a new class of side effects, known as immune-related adverse events (IRAEs). It is critical for the practicing radiologist to be able to recognize these events to best contribute to care for patients on checkpoint inhibitor immunotherapy. Here, we provide a comprehensive system-based review of immune-related adverse events and associated imaging findings. Further, we detail the best imaging modalities for each as well as describe problem solving modalities. Given that IRAEs can be subclinical before becoming clinically apparent, radiologists may be the first provider to recognize them, providing an opportunity for early treatment. Awareness of IRAEs and how to best image them will prepare radiologists to make a meaningful contribution to patient care as part of the clinical team.

A narrative review of the principal glucocorticoids employed in cancer

Glucocorticoids (GCs) are a pharmacological class of drugs widely used in oncology in both supportive and palliative settings. GCs differentially impact organs with immediate and long-term effects; with suppressive effect on the immune system anchoring their use to manage the toxicities of immune checkpoint inhibitors (ICIs). In addition, GCs are often used in the management of symptoms related to cancer or chemotherapy and as adjuvants in the treatment of pain in the management of other. In the palliative setting, GCs, especially administered subcutaneously can be to assist in the control of nausea, dyspnea, asthenia, and anorexia-cachexia syndrome. In this narrative review, we aim to summarize the role of GCs in the different settings (curative, supportive, and palliative) to help clinicians use these important drugs in their daily clinical practice with cancer patients.

Pembrolizumab-Induced Myasthenia Gravis and Myositis: Literature Review on Neurological Toxicities of Programmed Death Protein 1 Inhibitors

We present herein the case of an elderly male patient, who was receiving immunotherapy for his urothelial cancer and who presented to our facility with lower extremity weakness. The patient was diagnosed with myasthenia gravis, thyroiditis, myositis and myocarditis, which were considered as immune adverse events of pembrolizumab therapy. The patient received pyridostigmine, intravenous immunoglobulin, plasmapheresis, corticosteroids, and rituximab with mild improvement of his symptoms. The patient had some neurological recovery, was discharged to a nursing facility, however he was ventilator dependent. Of importance, our case is followed by review and discussion of the literature related to immunotherapy and its side effects.

Urinary incontinence as a possible signal of neuromuscular toxicity during immune checkpoint inhibitor treatment: Case report and retrospective pharmacovigilance study

Background

Immune checkpoint inhibitors (ICIs) are associated with different immune-related adverse events (irAEs), but there is limited evidence regarding the association between urinary incontinence and ICIs.

Methods

We described the case of a patient experiencing urinary incontinence who later experienced a series of irAEs such as myocarditis, myositis, and neurologic diseases while on ICI treatment in our hospital. In addition, we queried the Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) from the third quarter of 2010 to the third quarter of 2020 to perform a retrospective study to characterize the clinical features of urinary incontinence associated with ICIs.

Result

In the FAERS study, 59 cases of ICI-related urinary incontinence were retrieved, and approximately 32.2% of the cases were fatal. Combination therapy with nervous system drugs and age >80 years old were the significant risk factors for fatal outcomes. Among these cases of ICI-related urinary incontinence, 40.7% (n = 24) occurred concomitantly with other adverse events, especially, neurological (fifteen cases), cardiovascular (seven cases), musculoskeletal (six cases), and urological disorders (five cases). Five cases had an overlapping syndrome similar to our case report, including one case of myasthenia gravis with myocarditis and another of myasthenic syndrome with polymyositis.

Conclusion

ICI-related urinary incontinence might be a signal of fatal neuromuscular irAEs, especially when it occurs concomitantly with ICI-associated neuromuscular–cardiovascular syndrome. Clinicians should be aware of the occurrence of urinary incontinence to identify potentially lethal irAEs in the early phase.

[A case of myopathy, myocarditis, and encephalitis with nonconvulsive status epileptics after immune checkpoint inhibitor therapy for ureter cancer]

A 72-year-old man, who had received pembrolizumab of immune checkpoint inhibitor (ICI) over 6 months for ureter cancer, developed progressive skeletal muscle weakness, dysarthria, dyspnea, and consciousness disturbance over the past two weeks. The systemic work-up tests documented an encephalitis, myopathy, and myocarditis. Multiple autoimmune antibodies of anti-Tr, anti-titin, anti-kv1.4, anti-GM1 and anti-GD1a were positive in the serum. Although myopathy and myocarditis responded to high-dose steroid pulse therapy, encephalopathy deteriorated. Electroencephalogram showed a fluctuated pattern of rhythmic delta activity with fast waves, and a rapid response to intravenous diazepam revealed a condition of nonconvulsive status epileptics (NCSE). The patient had an uneventful course after anti-epileptic medication. The ICIs therapy may trigger a broader activation of multiple autoimmune mechanisms. When an encephalitis by immune-related adverse events does not respond to standard immunotherapy, NCSE may be a main pathophysiological mechanism, thereby anti-epileptics being an alternative treatment option.

Immune-checkpoint inhibitors: long-term implications of toxicity

The development of immune-checkpoint inhibitors (ICIs) has heralded a new era in cancer treatment, enabling the possibility of long-term survival in patients with metastatic disease, and providing new therapeutic indications in earlier-stage settings. As such, characterizing the long-term implications of receiving ICIs has grown in importance. An abundance of evidence exists describing the acute clinical toxicities of these agents, although chronic effects have not been as well catalogued. Nonetheless, emerging evidence indicates that persistent toxicities might be more common than initially suggested. While generally low-grade, these chronic sequelae can affect the endocrine, rheumatological, pulmonary, neurological and other organ systems. Fatal toxicities also comprise a diverse set of clinical manifestations and can occur in 0.4-1.2% of patients. This risk is a particularly relevant consideration in light of the possibility of long-term survival. Finally, the effects of immune-checkpoint blockade on a diverse range of immune processes, including atherosclerosis, heart failure, neuroinflammation, obesity and hypertension, have not been characterized but remain an important area of research with potential relevance to cancer survivors. In this Review, we describe the current evidence for chronic immune toxicities and the long-term implications of these effects for patients receiving ICIs.

Exploring the educational needs for severe immune-related adverse events of PD-1/PD-L1 inhibitors in advanced lung cancer : A single-center observational study

Objective

With the expanded use of immunotherapy in medical oncology, effective patient education regarding immune-related adverse events (irAEs) is crucial for oncology nursing. Therefore, this study aimed to identify educational needs for preventing unscheduled hospitalizations due to severe irAEs.

Methods

We retrospectively reviewed the medical records of 159 consecutive patients with lung cancer who received programmed cell death-1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors in 2020. We evaluated the frequency, severity, and unscheduled hospitalization due to irAEs based on the PD-1/PD-L1 inhibitor use. Educational needs were assessed based on initial symptoms, reporters, telephone consultation, and the time lag between symptom onset and hospital visit.

Results

Among 159 patients evaluable for irAEs, 73 (45.9%) experienced 91 irAEs during the study period. Seventeen patients (10.7%) required unscheduled hospitalization due to severe irAEs after a median duration of 4.1 days from symptom onset, and 52.9% visited hospitals after telephone consultations from caregivers. Pneumonitis (10 events) was the most frequent irAE requiring hospitalization, followed by adrenal insufficiency (three events). The type and severity of irAEs varied based on PD-1/PD-L1 inhibitor use.

Conclusions

The frequency of severe irAEs requiring hospitalization was high in patients who received PD-1/PD-L1 inhibitors for advanced lung cancer. The early detection of severe irAEs may be possible through education focusing on common irAEs that are potentially severe. Patients and caregivers should be aware of the importance of reporting slight changes in symptoms after PD-1/PD-L1 therapy initiation in a timely manner. Healthcare professionals need to acknowledge common irAEs and be qualified to implement systematic telephone triage of irAEs.

Review of Immune-Related Adverse Events (irAEs) in Non-Small-Cell Lung Cancer (NSCLC)—Their Incidence, Management, Multiorgan irAEs, and Rechallenge

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of advanced malignancies, including non-small cell lung cancer (NSCLC). These agents have improved clinical outcomes and have become quite an attractive alternative alone or combined with other treatments. Although ICIs are tolerated better, they also lead to unique toxicities, termed immune-related adverse events (irAEs). A reconstituted immune system may lead to dysregulation in normal immune self-tolerance and cause inflammatory side effects (irAEs). Although any organ system can be affected, immune-related adverse events most commonly involve the gastrointestinal tract, endocrine glands, skin, and liver. They can occur anytime during the treatment course and rarely even after completion. Owen and colleagues showed that approximately 30% of patients with NSCLC treated with ICIs develop irAEs. Kichenadasse et al. conducted a thorough evaluation of multiorgan irAEs, which is of particular interest because information regarding these types of irAEs is currently sparse. It is important to delineate between infectious etiologies and symptom progression during the management of irAEs. Close consultation with disease-specific subspecialties is encouraged. Corticosteroids are the mainstay of treatment of most irAEs. Early intervention with corticosteroids is crucial in the general management of immune-mediated toxicity. Grade 1–2 irAEs can be closely monitored; hypothyroidism and other endocrine irAEs may be treated with hormone supplementation without the need for corticosteroid therapy. Moderate- to high-dose steroids and other additional immunosuppressants such as tocilizumab and cyclophosphamide might be required in severe, grade 3–4 cases. Recently, increasing research on irAEs after immunotherapy rechallenge has garnered much attention. Dolladille and colleagues assessed the safety in patients with cancer who resumed therapy with the same ICIs and found that rechallenge was associated with about 25–30% of the same irAEs experienced previously (4). However, such data should be carefully considered. Further pooled analyses may be required before we conclude about ICIs’ safety in rechallenge.

Immunotherapy Associated Neurotoxicity in Pediatric Oncology

Novel immunotherapies are increasingly being employed in pediatric oncology, both in the upfront and relapsed/refractory settings. Through various mechanisms of action, engagement and activation of the immune system can cause both generalized and disease site-specific inflammation, leading to immune-related adverse events (irAEs). One of the most worrisome irAEs is that of neurotoxicity. This can present as a large spectrum of neurological toxicities, including confusion, aphasia, neuropathies, seizures, and/or death, with variable onset and severity. Earlier identification and treatment, generally with corticosteroids, remains the mainstay of neurotoxicity management to optimize patient outcomes. The pathophysiology of neurotoxicity varies across the different therapeutic strategies and remains to be elucidated in most cases. Furthermore, little is known about long-term neurologic sequelae. This review will focus on neurotoxicity seen with the most common immunotherapies used in pediatric oncology, including CAR T cell therapy, alternative forms of adoptive cell therapy, antibody therapies, immune checkpoint inhibitors, and tumor vaccines. Herein we will discuss the incidence, pathophysiology, symptomatology, diagnosis, and management strategies currently being utilized for immunotherapy-associated neurotoxicity with a focus on pediatric specific considerations.

Pembrolizumab-Related Side Effects: Acute Renal Failure and Severe Neurological Toxicity

Immunotherapy with immune checkpoint inhibitors represents nowadays a marked improvement in cancer treatment. Nevertheless, they can cause severe toxicities that put the patient at high risk, often requiring aggressive treatment. We present the case of a female patient who developed a severe immune-related adverse reaction to Pembrolizumab prescribed for melanoma treatment. Her array of symptoms, which presented a few days after last drug administration, consisted of severe neurological deficit, severe renal failure, polymyositis, and hyperthyroidism. Treatment required the immediate interruption of the trigger drug, infusion of high dose steroids, renal replacement therapy, plasmapheresis, and methimazole, as will be further discussed.

Biomarkers Associated with Immune-Related Adverse Events under Checkpoint Inhibitors in Metastatic Melanoma

Simple Summary

Our aim was to check for possible associations between clinical parameters or NGS-based genetic alterations and the occurrence of immune-related adverse events (IRAE) in melanoma patients with immune checkpoint inhibitors (ICI). We analyzed 95 melanoma patients with ICI and were able to identify several biomarkers associated with the development of IRAE. Female sex was significantly associated with the development of hepatitis, increased total and relative monocytes at ICI initiation were significantly associated with the development of pancreatitis, the same, pre-existing autoimmune diseases. Furthermore, the following genetic alterations were identified being associated with IRAE: SMAD3 (pancreatitis); CD274, SLCO1B1 (hepatitis); PRDM1, CD274 (encephalitis); PRDM1, CD274, TSHR, FAN1 (myositis). Myositis and encephalitis, both, were associated with alterations of PRDM1 and CD274, which might explain their joined appearance in clinical practice. Our findings can help to assess the risk for the development of IRAE in melanoma patients with ICI.

Abstract

Immune checkpoint inhibitors (ICI) have revolutionized the therapeutic landscape of metastatic melanoma. However, ICI are often associated with immune-related adverse events (IRAE) such as colitis, hepatitis, pancreatitis, hypophysitis, pneumonitis, thyroiditis, exanthema, nephritis, myositis, encephalitis, or myocarditis. Biomarkers associated with the occurrence of IRAE would be desirable. In the literature, there is only little data available and furthermore mostly speculative, especially in view of genetic alterations. Our major aim was to check for possible associations between NGS-based genetic alterations and IRAE. We therefore analyzed 95 melanoma patients with ICI and evaluated their NGS results. We checked the data in view of potential associations between copy number variations (CNVs), small variations (VARs), human leucocyte antigen (HLA), sex, blood count parameters, pre-existing autoimmune diseases and the occurrence of IRAE. We conducted a literature research on genetic alterations hypothesized to be associated with the occurrence of IRAE. In total, we identified 39 genes that have been discussed as hypothetical biomarkers. We compared the list of these 39 genes with the tumor panel that our patients had received and focused our study on those 16 genes that were also included in the tumor panel used for NGS. Therefore, we focused our analyses on the following genes: AIRE, TERT, SH2B3, LRRK2, IKZF1, SMAD3, JAK2, PRDM1, CTLA4, TSHR, FAN1, SLCO1B1, PDCD1, IL1RN, CD274, UNG. We obtained relevant results: female sex was significantly associated with the development of hepatitis, combined immunotherapy with colitis, increased total and relative monocytes at therapy initiation were significantly associated with the development of pancreatitis, the same, pre-existing autoimmune diseases. Further significant associations were as follows: HLA homozygosity (hepatitis), and VARs on SMAD3 (pancreatitis). Regarding CNVs, significant markers included PRDM1 deletions and IL1RN (IRAE), CD274 duplications and SLCO1B1 (hepatitis), PRDM1 and CD274 (encephalitis), and PRDM1, CD274, TSHR, and FAN1 (myositis). Myositis and encephalitis, both, were associated with alterations of PRDM1 and CD274, which might explain their joined appearance in clinical practice. The association between HLA homozygosity and IRAE was clarified by finding HLA-A homozygosity as determining factor. We identified several genetic alterations hypothesized in the literature to be associated with the development of IRAE and found significant results concerning pre-existing autoimmune diseases and specific blood count parameters. Our findings can help to better understand the development of IRAE in melanoma patients. NGS might be a useful screening tool, however, our findings have yet to be confirmed in larger studies.

Neurologic Complications of Immune Checkpoint Inhibitors

The clinical use of cancer immunotherapy with immune checkpoint inhibitors has transformed the management of cancer and added another effective treatment option for different types of malignancies. The blockade of immune checkpoint pathways triggers an enhanced immune response leading to cancer regression but may also lead to autoimmune toxicities or immune-related adverse events, which may involve skin, endocrine, respiratory, gastrointestinal or neurologic manifestations. Clinically relevant neurologic complications involving the central and/or peripheral nervous system affect up to 1% of patients treated with immune checkpoint inhibitors and may be associated with significant morbidity and mortality. Common neurologic complications include aseptic meningitis and encephalitis, hypophysitis, myasthenia, myositis and neuropathies. Neurologic immune-related adverse events after immune checkpoint inhibition should be distinguished from cancer progression or other complications of cancer therapy (e.g. infections). The treatment of neurologic complications may include holding or withdrawing cancer immunotherapy, anti-inflammatory and immunosuppressive therapies with corticosteroids and steroid-sparing agents, immunomodulation with intravenous immune globulin or plasmapheresis and symptomatic treatment (e.g. antiepileptic medications, pain medications).

Evaluation of headache in patients with cancer

Headache is a common complaint and is often benign. When patients with cancer describe new headaches, it is important to ensure that there are no emergent or concerning etiologies, including metastatic disease. This review article details primary and secondary headaches. Red flags-the do-not-miss warning signs-are described. An initial approach to the evaluation, including suggestions for imaging, features to look for in a targeted examination, and when to request a consultation, is outlined. An overview of headache etiologies is described with a particular emphasis on the most common types: migraine and tension. The classification of headaches, based on criteria from the International Classification of Headache Disorders (3rd edition; beta version), is reviewed. Medications used for treatment, including newer biological agents, are described, and there are details about both abortive and preventive medication therapies. Suggestions for complementary and integrative therapies, some of which may be synergistic in treating other cancer symptoms, are outlined; they include mindfulness therapies, which are gaining traction in treating a variety of medical conditions. Readers should have an understanding of headache evaluation in patients with cancer and should know how to formulate a plan for a diagnosis. In addition, readers will gain familiarity with common treatments, both pharmacological and complementary/integrative.

Anti-γ-Aminobutyric Acid Type β Receptor Antibody-Associated Encephalitis After 2 Cycles of Durvalumab Therapy in a Patient with Small Cell Lung Cancer: A Case Report

Anti-γ-aminobutyric acid type β receptor (anti-GABA_BR) antibody-associated encephalitis is a type of autoimmune encephalitis. According to current literature, its pathogenesis is reported to be closely related to tumor factors. However, diagnosis can be difficult because of the rarity of cases, limited clinical understanding, and a lack of specificity in clinical manifestation and imaging presentation. Clinical trials have demonstrated that immunotherapy can prolong the survival of patients with small cell lung cancer; however, in some cases, immunotherapy may induce anti-GABA_BR antibody-associated encephalitis. Patients who develop this encephalitis during immunotherapy often delay treatment because the cause is not clearly identified. In this study, we report a case of a 61-year-old man with a confirmed diagnosis of small cell lung cancer who had acute onset of cognitive impairment and seizures after two cycles of durvalumab (AstraZeneca UK Limited) combination chemotherapy. This reaction was initially considered as an immune-related adverse event (irAE) caused by durvalumab treatment, and the patient was eventually considered to have a paraneoplastic neurological disorder caused by the primary tumor. This report raises awareness of the symptoms of cognitive impairment and seizures in patients with small cell lung cancer, and the possible adverse events associated with immunotherapy. This case also highlights the importance of detecting anti-GABA_BR antibodies in patients with small cell lung cancer.

Management of Immune-Related Adverse Events in Patients Treated With Immune Checkpoint Inhibitor Therapy: ASCO Guideline Update

PURPOSE

To increase awareness, outline strategies, and offer guidance on the recommended management of immune-related adverse events (irAEs) in patients treated with immune checkpoint inhibitor (ICPi) therapy.

METHODS

A multidisciplinary panel of medical oncology, dermatology, gastroenterology, rheumatology, pulmonology, endocrinology, neurology, hematology, emergency medicine, nursing, trialists, and advocacy experts was convened to update the guideline. Guideline development involved a systematic literature review and an informal consensus process. The systematic review focused on evidence published from 2017 through 2021.

RESULTS

A total of 175 studies met the eligibility criteria of the systematic review and were pertinent to the development of the recommendations. Because of the paucity of high-quality evidence, recommendations are based on expert consensus.

RECOMMENDATIONS

Recommendations for specific organ system-based toxicity diagnosis and management are presented. While management varies according to the organ system affected, in general, ICPi therapy should be continued with close monitoring for grade 1 toxicities, except for some neurologic, hematologic, and cardiac toxicities. ICPi therapy may be suspended for most grade 2 toxicities, with consideration of resuming when symptoms revert ≤ grade 1. Corticosteroids may be administered. Grade 3 toxicities generally warrant suspension of ICPis and the initiation of high-dose corticosteroids. Corticosteroids should be tapered over the course of at least 4-6 weeks. Some refractory cases may require other immunosuppressive therapy. In general, permanent discontinuation of ICPis is recommended with grade 4 toxicities, except for endocrinopathies that have been controlled by hormone replacement. Additional information is available at www.asco.org/supportive-care-guidelines.

A review of neurotoxicities associated with immunotherapy and a framework for evaluation

Immuno-oncology agents, including immune checkpoint inhibitors (ICIs) and chimeric antigen receptor T (CAR-T) cell therapies, are increasing in use for a growing list of oncologic indications. While harnessing the immune system against cancer cells has a potent anti-tumor effect, it can also cause widespread autoimmune toxicities that limit therapeutic potential. Neurologic toxicities have unique presentations and can progress rapidly, necessitating prompt recognition. In this article, we review the spectrum of central and peripheral neurologic immune-related adverse events (irAEs) associated with ICI therapies, emphasizing a diagnostic framework that includes consideration of the therapy regimen, timing of symptom onset, presence of non-neurologic irAEs, pre-existing neurologic disease, and syndrome specific features. In addition, we review the immune effector cell-associated neurotoxicity syndrome (ICANS) associated with CAR-T cell therapy and address diagnostic challenges specific to patients with brain metastases. As immunotherapy use grows, so too will the number of patients affected by neurotoxicity. There is an urgent need to understand pathogenic mechanisms, predictors, and optimal treatments of these toxicities, so that we can manage them without sacrificing anti-tumor efficacy.

Development of preclinical and clinical models for immune-related adverse events following checkpoint immunotherapy: a perspective from SITC and AACR

Recent advances in cancer immunotherapy have completely revolutionized cancer treatment strategies. Nonetheless, the increasing incidence of immune-related adverse events (irAEs) is now limiting the overall benefits of these treatments. irAEs are well-recognized side effects of some of the most effective cancer immunotherapy agents, including antibody blockade of the cytotoxic T-lymphocyte-associated protein 4 and programmed death protein 1/programmed-death ligand 1 pathways. To develop an action plan on the key elements needed to unravel and understand the key mechanisms driving irAEs, the Society for Immunotherapy for Cancer and the American Association for Cancer Research partnered to bring together research and clinical experts in cancer immunotherapy, autoimmunity, immune regulation, genetics and informatics who are investigating irAEs using animal models, clinical data and patient specimens to discuss current strategies and identify the critical next steps needed to create breakthroughs in our understanding of these toxicities. The genetic and environmental risk factors, immune cell subsets and other key immunological mediators and the unique clinical presentations of irAEs across the different organ systems were the foundation for identifying key opportunities and future directions described in this report. These include the pressing need for significantly improved preclinical model systems, broader collection of biospecimens with standardized collection and clinical annotation made available for research and integration of electronic health record and multiomic data with harmonized and standardized methods, definitions and terminologies to further our understanding of irAE pathogenesis. Based on these needs, this report makes a set of recommendations to advance our understanding of irAE mechanisms, which will be crucial to prevent their occurrence and improve their treatment.

Encephalitis Induced by Durvalumab During Treatment of Metastatic Small-Cell Lung Cancer: Illustrative Case and Review of the Literature

The immune checkpoint inhibitors have improved the standards of care in cancer treatment and have dramatically improved patient prognoses. These new antibodies turned to be an integral part of the standard of care for metastatic small-cell lung cancer. Platinum-based chemotherapy combined with checkpoint inhibitors, resulted in statistically significant improvement of progression free survival and overall survival. Immune checkpoint inhibitors immune-related adverse events have been observed and reported as a consequence of administering these innovative treatment drugs. Neurological immune-related adverse events are rare complications; however, they can be potentially fatal, particularly encephalitis. This report describes a 66-year-old female who received Durvalumab for metastatic small-cell lung cancer. Following 3 cycles of treatment, she developed encephalitis.

Presynaptic Paraneoplastic Disorders of the Neuromuscular Junction: An Update

The neuromuscular junction (NMJ) is the target of a variety of immune-mediated disorders, usually classified as presynaptic and postsynaptic, according to the site of the antigenic target and consequently of the neuromuscular transmission alteration. Although less common than the classical autoimmune postsynaptic myasthenia gravis, presynaptic disorders are important to recognize due to the frequent association with cancer. Lambert Eaton myasthenic syndrome is due to a presynaptic failure to release acetylcholine, caused by antibodies to the presynaptic voltage-gated calcium channels. Acquired neuromyotonia is a condition characterized by nerve hyperexcitability often due to the presence of antibodies against proteins associated with voltage-gated potassium channels. This review will focus on the recent developments in the autoimmune presynaptic disorders of the NMJ.

Consensus disease definitions for neurologic immune-related adverse events of immune checkpoint inhibitors

Expanding the US Food and Drug Administration-approved indications for immune checkpoint inhibitors in patients with cancer has resulted in therapeutic success and immune-related adverse events (irAEs). Neurologic irAEs (irAE-Ns) have an incidence of 1%-12% and a high fatality rate relative to other irAEs. Lack of standardized disease definitions and accurate phenotyping leads to syndrome misclassification and impedes development of evidence-based treatments and translational research. The objective of this study was to develop consensus guidance for an approach to irAE-Ns including disease definitions and severity grading. A working group of four neurologists drafted irAE-N consensus guidance and definitions, which were reviewed by the multidisciplinary Neuro irAE Disease Definition Panel including oncologists and irAE experts. A modified Delphi consensus process was used, with two rounds of anonymous ratings by panelists and two meetings to discuss areas of controversy. Panelists rated content for usability, appropriateness and accuracy on 9-point scales in electronic surveys and provided free text comments. Aggregated survey responses were incorporated into revised definitions. Consensus was based on numeric ratings using the RAND/University of California Los Angeles (UCLA) Appropriateness Method with prespecified definitions. 27 panelists from 15 academic medical centers voted on a total of 53 rating scales (6 general guidance, 24 central and 18 peripheral nervous system disease definition components, 3 severity criteria and 2 clinical trial adjudication statements); of these, 77% (41/53) received first round consensus. After revisions, all items received second round consensus. Consensus definitions were achieved for seven core disorders: irMeningitis, irEncephalitis, irDemyelinating disease, irVasculitis, irNeuropathy, irNeuromuscular junction disorders and irMyopathy. For each disorder, six descriptors of diagnostic components are used: disease subtype, diagnostic certainty, severity, autoantibody association, exacerbation of pre-existing disease or de novo presentation, and presence or absence of concurrent irAE(s). These disease definitions standardize irAE-N classification. Diagnostic certainty is not always directly linked to certainty to treat as an irAE-N (ie, one might treat events in the probable or possible category). Given consensus on accuracy and usability from a representative panel group, we anticipate that the definitions will be used broadly across clinical and research settings.

Critically ill patients with severe immune checkpoint inhibitor related neurotoxicity: A multi-center case series

PURPOSE

Serious immune checkpoint inhibitor (ICI)-related neurotoxicity is rare. There is limited data on the specifics of care and outcomes of patients with severe neurological immune related adverse events (NirAEs) admitted to the Intensive Care Unit (ICU).

MATERIALS AND METHODS

Retrospective study of patients with severe NirAEs admitted to the ICU at 3 academic centers between January 2016 and December 2018. Clinical data collected included ICI exposure, type of NirAE (central [CNS] or peripheral nervous system [PNS) disorders), and patient outcomes including neurological recovery and mortality.

RESULTS

Seventeen patients developed severe NirAEs. Eight patients presented with PNS disorders; 6 with myasthenia gravis (MG), 1 had a combination of MG and polyneuropathy and 1 had Guillain-Barre syndrome. Nine patients had CNS disorders (6 seizures and 5 had concomitant encephalopathy. During ICU admission, 65% of patients required mechanical ventilation, 35% vasopressors, and 18% renal replacement therapy. The median ICU and hospital length of stay were 7 (2-36) and 18 (4-80) days, respectively. Hospital mortality was 29%. At hospital discharge, 18% of patients made a full neurologic recovery, 41% partial recovery, and 12% did not recover.

CONCLUSION

Severe NirAEs while uncommon, can be serious or even life-threatening if not diagnosed and treated early.

A systematic review of immune checkpoint inhibitor-related neurological adverse events and association with anti-neuronal autoantibodies

Introduction: Immune checkpoint inhibitors (ICI) therapy has led to a paradigm shift in cancer drug development and in the clinical evaluation of approaches to combination cancer treatment. Dysregulation of the immune system by ICI therapy may also elicit autoimmune phenomena and consequently manifest clinically as immune-related adverse events (irAEs) including neurological irAEs. Areas Covered: The purpose of this review is to explore the role of autoantibodies in the diagnosis and prediction of neurological irAEs and to evaluate their pathogenicity. We searched Pubmed and Embase for neurological irAEs and associated autoantibodies and found 28 patients with central and peripheral neurological irAEs. Of these patients, up to 40% had encephalitis, 34.4% with myasthenia gravis and 22% of patients with peripheral neuropathy and Guillain-Barre Syndrome had autoantibodies. Expert Opinion: Overall, our survey suggested a causal relationship between neurological irAEs and autoantibodies. Detection of autoantibodies may help to diagnose neurological irAEs and inform their clinical management.

Immune checkpoint inhibitor-induced aseptic meningitis and encephalitis: a case-series and narrative review

BACKGROUND

Along with the increasing use of immune checkpoint inhibitors comes a surge in immune-related toxicity. Here, we review the currently available data regarding neurological immune adverse events, and more specifically aseptic meningitis and encephalitis, and present treatment and diagnostic recommendations. Furthermore, we present five cases of immunotherapy-induced aseptic meningitis and encephalitis treated at our institution.

RECENT FINDINGS

Neurological immune-related adverse events, including aseptic meningitis and encephalitis, secondary to checkpoint inhibitors are a rare but complex and clinically relevant entity, comprising a wide range of diseases, most often presenting with symptoms with a wide range of differential diagnoses. Our case-series highlights the challenges of such entities and the importance of properly identifying and managing aseptic meningitis and encephalitis.

SUMMARY

Checkpoint inhibitor-induced meningoencephalitis warrants prompt investigations and treatment. Properly diagnosing aseptic meningitis, encephalitis, or mixed presentations may guide the treatment decision, as highlighted by our case-series. After rapid exclusion of alternative diagnoses, urgent corticosteroids are the therapeutic backbone but this could change in favour of highly specific cytokine-directed treatment options.

PLAIN LANGUAGE SUMMARY

Aseptic meningitis and encephalitis with immune checkpoint inhibitors: a single centre case-series and review of the literature Over the course of the past decade, checkpoint inhibitors have revolutionized cancer care. With their favourable toxicity profile and potential for durable and deep responses, they have become ubiquitous across the field of oncology. Furthermore, combination checkpoint inhibitors are also gaining ground, with increased efficacy and, unfortunately, immune-related toxicity. While there are guidelines based on extensive clinical experience for frequent adverse events, uncommon entities are less readily identified and treated. Neurological immune-related adverse events secondary to checkpoint inhibitors are a rare but complex entity, comprising a wide range of diseases, most often presenting with aspecific symptoms. In this paper, we discuss a single institution case-series of patients with autoimmune aseptic meningitis and encephalitis, and we perform a narrative literature review on this subject. We conclude with our treatment recommendations based on available evidence.

Systemic adverse effects and toxicities associated with immunotherapy: A review

Immunotherapy is rapidly evolving secondary to the advent of newer immunotherapeutic agents and increasing approval of the current agents by the United States Food and Drug Administration to treat a wide spectrum of cancers. Immunotherapeutic agents have gained immense popularity due to their tumor-specific action. Immunotherapy is slowly transforming into a separate therapeutic entity, and the fifth pillar of management for cancers alongside surgery, radiotherapy, chemotherapy, and targeted therapy. However, like any therapeutic entity it has its own adverse effects. With the increasing use of immuno-therapeutic agents, it is vital for physicians to acquaint themselves with these adverse effects. The aim of this review is to investigate the common systemic adverse effects and toxicities associated with the use of different classes of immunotherapeutic agents. We provide an overview of potential adverse effects and toxicities associated with different classes of immunotherapeutic agents organized by organ systems, as well as an extensive discussion of the current recommendations for treatment and clinical trial data. As we continue to see increasing usage of these agents in clinical practice, it is vital for physicians to familiarize themselves with these effects.

Myositis and myasthenia during nivolumab administration for advanced lung cancer: a case report and review of the literature

The immunotherapy significantly improved survival of non-small cell lung cancer patients, but it may cause immune-related adverse events, which are severe in less than 10% of cases. We report the case of one patient who developed myositis and myasthenia during nivolumab treatment for metastatic lung squamous carcinoma. Moreover, we reviewed literature data in order to identify similar cases in cancer patients treated with immune-checkpoints inhibitors. A 65-year-old patient, who had previously received a first-line platinum-based therapy, developed diplopia and ptosis 4 weeks after the start of nivolumab. Although antibodies associated with myositis, myasthenia gravis and paraneoplastic syndromes were absent, immune-related myositis and myasthenia were diagnosed. Corticosteroids, immunoglobulin and pyridostigmine showed poor efficacy and the patient died 7 weeks after the appearance of the first symptoms. Fifteen similar cases were found in the literature. A close collaboration between different specialists is essential to rapidly identify and treat severe immune-related adverse events.

Brain Stem Encephalitis in a Patient With Recurrent Small Cell Lung Cancer Treated With Immune Checkpoint Inhibitor: Case Presentation and Review of the Literature

Immunotherapy with checkpoint inhibitors (CPIs) has revolutionized the management of advanced cancer including advanced small cell lung cancer (SCLC). Unfortunately, those agents are not without adverse effects. Immune imbalance through enhanced cellular immune response may result in impaired endogenous immunological tolerance mechanisms that can result in a wide spectrum of immunological side effects also known as immune-related adverse events (irAEs). Scarce data are currently available about neurological immune-related adverse events (neuro irAEs), mainly obtained from clinical trials, case reports, or small case series. Most reported cases presented with nonspecific symptoms. It is important to recognize and promptly treat neuro irAEs, as it may be serious and even potentially fatal.

We present a rare case of nivolumab induced brain stem encephalitis in a patient with advanced SCLC presented 10 months after starting treatment with symptoms of nystagmus, gait disturbance, and blurry vision. Nivolumab was held and the patient was started on oral steroids with tapering dose. The patient’s symptoms gradually improved over a few weeks. Re-challenging with nivolumab six weeks later resulted in recurrence of symptoms and again the patient was prescribed oral steroids with tapering dose. She maintained response off treatment for six months. This case report is aimed to highlight the importance of clinically suspecting and promptly treating neurological irAE, when managing a patient with CPIs.

Neuroimmunological adverse events associated with immune checkpoint inhibitor: a retrospective, pharmacovigilance study using FAERS database

PURPOSE

To investigate the characteristics and risk factors for neurologic adverse events (AEs) induced by immune checkpoint inhibitors (ICIs).

METHODS

An observational, retrospective, and pharmacovigilance study based on the FAERS database collected between January 2014 and December 2019 was conducted. ICI-related AEs were defined as adverse reactions in patients using anti-PD-1 (nivolumab and pembrolizumab), anti-PD-L1 (atezolizumab, avelumab, and durvalumab), and anti-CTLA-4 (ipilimumab and tremelimumab). Neurologic AEs previously reported to be associated with ICI were evaluated in the disproportionality analysis using the reporting odds ratio (ROR).

RESULTS

Among 50,406 ICI-related reports, 3619 (7.2%) neurological case was found: 1985 with anti-PD-1, 372 with anti-PD-L1, 366 with anti-CTLA-4, and 896 with the combination of ICIs. In comparison to non-ICI drug use, ICI use demonstrated higher risk for neurologic complication, including hypophysitis/hypopituitarism, myasthenia gravis, encephalitis/myelitis, meningitis, Guillain-Barre syndrome, vasculitis, and neuropathy. The risk of neurologic AEs associated with ICI combination therapy was as high as or even higher than ICI monotherapy, most significantly in hypophysitis/hypopituitarism. The proportion of serious neurological events and death related to combination therapy has been decreasing in recent years. Older age, male and female sex, and metastasis were not significant risk factors for the incidence of neurologic ICI-related AEs. Patients at older age, with melanoma or non-small cell lung cancer, or on dual ICI therapy may be at higher risk of fatal neurologic AEs.

CONCLUSION

ICI use is associated with a higher risk of neurological complications, with dual ICI therapy posing a higher risk, while older age, sex, or metastasis were not. Patients at older age, with certain cancer types, or on dual ICI therapy may be at higher risk of fatal neurologic AEs.