With their groundbreaking clinical responses, immune checkpoint inhibitors (ICIs) have ushered in a new chapter in cancer therapeutics. However, they are often associated with life-threatening or organ-threatening autoimmune/autoinflammatory phenomena, collectively termed immune-related adverse events (irAEs). In this review, we will first describe the mechanisms of action of ICIs as well as irAEs. Next, we will review biomarkers for predicting the development of irAEs or stratifying risks.

Immune checkpoint inhibitors (ICI) are highly effective but may induce severe or even fatal and unpredictable immune-related adverse events (irAEs). It is unclear whether human leukocyte antigen (HLA) genes contribute to the susceptibility of developing irAEs during ICI therapy.

This multicentre retrospective study investigated the association of irAE and outcome with HLA-A*02:01 status in a cohort of 97 patients with metastatic melanoma undergoing ICI therapy. Organ-specific irAEs and therapy outcome as assessed by response rate, progression-free survival (PFS) and overall survival (OS) were analysed depending on HLA type HLA-A*02:01. For the outcome only patients with cutaneous melanoma were analysed. Chi square test, exact fisher test, Kruskal Wallis test and log rank test were employed for statistical analysis (p ≤ 0.05).

The cohort included 38 HLA-A*02:01 positive (39.2%) and 59 HLA-A*02:01 negative (60.8%) patients. Data showed no evidence of an association of HLA-A*02:01 with organ-specific irAEs except for a numerical difference in immune-related colitis. Furthermore, response rates of the subgroup of patients with metastatic cutaneous melanoma did not differ between the two cohorts. The median PFS was 5 months and 8 months in HLA-A*02:01 positive and negative patients with cutaneous melanoma, respectively.

HLA-A*02:01 was not associated with specific checkpoint inhibitor-induced organ toxicity in this cohort of HLA-A-typed melanoma patients. Interestingly, in the relatively small subgroup of patients with cutaneous melanoma an earlier progression in HLA-A*02:01 positive patients was observed, however not in the long term. These findings are exploratory due to the limited sample size and require validation in larger, prospective cohorts.

Immune-related adverse events (irAE) pose challenges to the use of immune checkpoint inhibitors (ICI). While risk factors for irAE are emerging, most studies are small, retrospective analyses that seldom report on diverse cancers or rare irAE. This paper reports a systematic review that summarises literature on irAE risk factors across cancers and proposes a categorisation approach.

A systematic search was conducted in Medline OVID, Embase and Web of Science databases following PRISMA guidelines (CRD42022310127). Original research published in peer-reviewed journals between January 2017-Decmeber 2021 were selected. Eligible studies included patients with any cancer and evaluated any potential risk factor for any grade/type of irAE. Study design, sample size, and method for analysing association between irAE and risk factors were compared.

A total of 293 eligible studies containing 305,879 patients receiving ICI reported irAE in 58,291 patients (19.1 %). There were 221 retrospective, 55 prospective studies, and 17 systematic reviews/meta-analyses. Eighteen studies evaluated the predictive validity of models. Proposed risk factors were grouped based on common themes and underlying aetiology: 1) patient, 2) laboratory, 3) medical history, 4) cancer-related, 5) clinical score, 6) medications, and 7) imaging features. Opposing associations were reported between advancing age and irAE risk.

This systematic review provides a comprehensive overview of evidence on irAE risk factors across a large patient population. Studies were heterogeneous resulting from variations in design, sample size and analysis method, and lack generalisability due to statistically underpowered evidence. We propose an approach to categorise potential irAE risk factors to support ongoing collaborative research.

Immune checkpoint inhibitors (ICIs) have led to improved outcome in patients with various types of cancer. Due to inhibition of physiological anti-inflammatory mechanisms, patients treated with ICIs may develop autoimmune inflammation of the colon, associated with morbidity, decreased quality of life (QoL), and mortality. In this review, we summarize clinical and pathophysiological aspects of immune-mediated colitis (ImC), highlighting novel treatment options. In the colon, ICIs trigger resident and circulating T cell activation and infiltration of myeloid cells. In addition, the gut microbiota critically contribute to intestinal immune dysregulation and loss of barrier function, thereby propagating local and systemic inflammation. Currently available therapies for ImC include corticosteroids, antitumor necrosis factor-α (TNF-α)- and anti-integrin α4β7 antibodies. Given that systemic immunosuppression might impair antitumor immune responses, novel therapeutic approaches are urgently needed.

Immunotherapy has changed the treatment landscape for patients with cancer in the past decade. Immune checkpoint inhibitor (ICI)-based therapies have proven effective in a range of malignancies, including liver and gastrointestinal cancers, but they can cause diverse off-target organ toxicities. With the increasingly wider application of these drugs, immune-mediated liver injury from ICIs has become a commonly encountered challenge in clinical hepatology and gastroenterology. In this Review, we discuss the evidence from human and animal studies on the immunological mechanisms of immune-mediated liver injury from ICIs and summarize its clinical features and practical considerations for its management.

Background/Objectives: Earlier detection of severe immune-related hematological adverse events (irHAEs) in cancer patients treated with a PD-1 or PD-L1 inhibitor is critical to improving treatment outcomes. The study aimed to develop a simple machine learning (ML) model for predicting irHAEs associated with PD-1/PD-L1 inhibitors. Methods: We utilized the Observational Medical Outcomes Partnership-Common Data Model based on electronic medical records from a tertiary (KHMC) and a secondary (KHNMC) hospital in South Korea. Severe irHAEs were defined as Grades 3-5 by the Common Terminology Criteria for Adverse Events (version 5.0). The predictive model was developed using the KHMC dataset, and then cross-validated against an independent cohort (KHNMC). The full ML models were then simplified by selecting critical features based on the feature importance values (FIVs). Results: Overall, 397 and 255 patients were included in the primary (KHMC) and cross-validation (KHNMC) cohort, respectively. Among the tested ML algorithms, random forest achieved the highest accuracy (area under the receiver operating characteristic curve [AUROC] 0.88 for both cohorts). Parsimonious models reduced to 50% FIVs of the full models showed comparable performance to the full models (AUROC 0.83-0.86, p > 0.05). The KHMC and KHNMC parsimonious models shared common predictive features including furosemide, oxygen gas, piperacillin/tazobactam, and acetylcysteine. Conclusions: Considering the simplicity and adequate predictive performance, our simplified ML models might be easily implemented in clinical practice with broad applicability. Our model might enhance early diagnostic screening of irHAEs induced by PD-1/PD-L1 inhibitors, contributing to minimizing the risk of severe irHAEs and improving the effectiveness of cancer immunotherapy.

The immune system is one of the common targets of drugs' toxicity (Immunotoxicity) and/or efficacy (Immunotherapy). Immunotoxicity leads to adverse effects on human health, which raises serious concerns for the regulatory agencies. Currently, immunotoxicity assessment is conducted using different in vitro and in vivo assays. In silico and in vitro human cell-based immunotoxicity assays should also be explored for screening purposes as these are time and cost effective as well as for ethical reasons. For in vivo studies, tier 1-3 assessments (Tier 1: hematology, serum globulin levels, lymphoid organ's weight and histopathology; Tier 2: immunophenotyping, TDAR and cell mediated immunity; and Tier 3: host resistance) should be used. These non-clinical in vivo assessments are useful to select immunological endpoints for clinical trials as well as for precautionary labeling. As per regulatory guidelines, adverse immunogenicity information of drug should be included in product's labeling to make health care practitioner aware of safety concerns before prescribing medicines and patient management (USFDA, 2022a, 2022b). This review mainly focuses on the importance of immunotoxicity assessment during drug discovery and development.

Immune-related adverse events (irAE) induced by immune checkpoint inhibitors (ICI) are a treatment-limiting barrier. There are few large-scale studies that estimate irAE prevalence. This paper presents a systematic review that reports the prevalence of irAE by cancer type and ICI.

A systematic review was undertaken in MEDLINE OVID, EMBASE and Web of Science databases from 2017-2021. A total of 293 studies were identified for analysis and, of these, event rate was calculated for 272 studies, which involved 58,291 patients with irAE among 305,879 total patients on ICI. Event rate was calculated by irAE and ICI type.

Mean event rate for general irAE occurrence across any grade was 40.0% (37.3-42.7%) and high grade was 19.7% (15.8-23.7%). Mean event rates for six specific types of irAE are reported. Mean event rate for ICI monotherapy was 30.5% (28.1-32.9%), 45.7% (29.6-61.7%) for ICI combination therapy, and 30.0% (25.3-34.6%) for both ICI monotherapy and combination therapy.

This systematic review characterises irAE prevalence across current research that examines irAE risk factors across cancers and ICI. The findings confirms that irAE occurrence is very common in the real-world setting, both high grade and irAE across any grade.

Checkpoint inhibitors are increasingly important in anti-cancer treatment. Therefore, knowledge of immune-related cutaneous adverse events (ir-cAE) is crucial for therapy management and continuation.

The study aimed to analyze the incidence of cutaneous adverse events caused by checkpoint inhibitor therapy, including their clinical presentation, management, and impact on further treatment.

This is a descriptive, monocentric retrospective study that uses data from the electronic health record system at a tertiary referral hospital in Central Switzerland from September 2019 to September 2022. The electronic health records of patients who received a therapy with checkpoint inhibitors were examined for age, sex, type of immunotherapy, time to occurrence of ir-cAEs, characteristics of the ir-cAEs, the treatment approach, and the continuation or cessation of the therapy due to ir-cAEs.

Out of 431 patients, for 131 patients (30.4%) at least one ir-cAE event was documented. In particular, 109 (25.3%) experienced pruritus and 61 (14.2%) showed a maculopapular exanthema. The severity of the ir-cAE was mild in 88 patients (67.2% out of those with ir-cAEs). Ir-cAE were observed in 10 out of 20 patients (50%) treated with ipilimumab/nivolumab and in 15 out of 24 (62.5%) treated with durvalumab. In 15 patients (3.5%), checkpoint inhibitor therapy had to be discontinued due to cutaneous side effects.

This study showed that approximately one third of the patients experienced ir-cAEs. The most frequently observed ir-cAEs were pruritus, maculopapular exanthema and xerosis cutis. In general, the dermatological manifestations are mild and responsive to topical treatment or self-limiting with no requirement for treatment interruption.

Immune checkpoint inhibitors lead to effective antitumour responses but also to immune-related adverse events (irAEs), which affect the nervous system in 1-5% of patients. Encephalitis is the most frequent central nervous system irAE and is clinically relevant due to its high severity and mortality. Early diagnosis is crucial but is hampered by the broad list of alternative diagnoses, the lack of established diagnostic criteria, and the need of extensive diagnostic procedures (e.g., spinal tap, brain MRI) alongside expert neurological evaluation. Additionally, the response to corticosteroids is inconsistent, and the management of corticosteroid-refractory patients remains poorly defined. This mini-review discusses the role of various soluble biomarkers in the diagnosis, prognostication, and management of ICI-encephalitis. Neural antibodies, which are well-established biomarkers of autoimmune and paraneoplastic encephalitis, are found in only a subset of ICI-encephalitis, in which they can aid to establish the diagnosis. The most prevalent are paraneoplastic neurological syndromes (PNS)-associated antibodies, which are found almost exclusively in focal ICI-encephalitis syndromes and are associated with poor outcomes, possibly due to predominantly cytotoxic T cell involvement leading to irreversible neuronal loss. Beside antibodies, serum brain injury biomarkers such as NfL and S100B are elevated in ICI-encephalitis and, even if non-specific, may be useful as a routine test to quickly identify patients in whom neurological evaluation and second-level diagnostic procedures should be prioritized. Additionally, higher serum and CSF NfL levels have been associated with lack of treatment response in ICI-encephalitis, suggesting they may have a prognostic role. Among cytokines, elevated interleukin 6 (IL6) levels have been observed in serum and/or CSF samples of some patients with ICI-encephalitis, but the role of IL6 as a biomarker for response to IL6-directed therapies requires further investigation. Likewise, the value of other biomarkers, including T cells markers and HLA haplotypes, still needs to be evaluated in large cohorts. Overall, neural antibodies are important diagnostic and prognostic biomarkers in ICI-encephalitis, and other soluble biomarkers, especially NfL, deserve further investigation since they have a promising application in clinical practice.

Almost one-quarter of immune checkpoint inhibitor (ICI) recipients experience sicca syndrome, while Sjögren's disease (SjD) is estimated at 0.3-2.5%, possibly underreported.

This narrative review (Medline/Embase until January/31/2024) addresses the pathophysiology, incidence, demographic/clinical features, biomarkers, labial salivary gland biopsy (LSGB), fulfillment of the idiopathic SjD (iSjD) classificatory criteria, differential diagnosis, and management of sicca syndrome/SjD associated with ICIs.

SjD associated with ICIs is underdiagnosed, since studies that performed the mandatory SjD investigation identified that 40-60% of patients with sicca syndrome associated with ICIs meet the iSjD classificatory criteria. LSGB played a fundamental role in recognizing these cases, as most of them had negative anti-Ro/SS-A antibody. Despite the finding of focal lymphocytic sialoadenitis in LSGB samples mimicking iSjD, immunohistochemical analysis provided novel evidence of a distinct pattern for sicca syndrome/SjD associated with ICIs compared to iSjD. The former has scarcity of B lymphocytes, which are a hallmark of iSjD. Additionally, patients with sicca syndrome/SjD associated with ICIs have demographical/clinical/serological and treatment response dissimilarities compared to iSjD. Dryness symptoms are more acute in the former than in iSjD, with predominance of xerostomia over xerophthalmia, and partial/complete response to glucocorticoids. Dryness symptoms in ICI-treated patients warrant prompt SjD investigation.

Maximal heterozygosity on the human leukocyte antigen (HLA) loci has been found to be associated with improved survival and development of immune-related adverse events (irAEs) among NSCLC patients treated with immunotherapy. Here, we investigated the effect of germline HLA-I/-II on clinical outcomes among NSCLC patients treated with first-line pembrolizumab in combination with chemotherapy.

We prospectively recruited patients with NSCLC who were commencing first-line pembrolizumab in combination with chemotherapy. DNA from white blood cells was used for high-resolution HLA-I/II typing.

Of the 65 patients recruited, 53 complied with the inclusion criteria. We did not find an association between HLA-I/-II homozygosity and clinical outcome among the studied population. However, the presence of HLA-A01 was associated with unfavourable PFS (HR = 2.32, 95%CI 1.13-4.77, p = 0.022) and worsening OS (HR = 2.86, 95%CI 1.06-7.70, p = 0.038). The presence of HLA-B27 was associated with improved PFS (HR = 0.35, 95%CI 0.18-0.71, p = 0.004) and trends toward improving OS. None of the HLA-I supertypes were associated with the development or worsening of irAEs.

The absence of association between genomic HLA-I/-II homozygosity and clinical outcome among patients with advanced NSCLC treated with pembrolizumab in combination with chemotherapy might reflect a diminished role for HLA molecules among patients with low or no PD-L1. HLA-A01 and HLA-B27 might have a role in predicting clinical outcomes among this cohort of patients. Further studies are needed to explore biomarkers for this group of patients.

Immune checkpoint inhibitors (ICIs) constitute a pivotal class of immunotherapeutic drugs in cancer treatment. However, their widespread clinical application has led to a notable surge in immune-related adverse events (irAEs), significantly affecting the efficacy and survival rates of patients undergoing ICI therapy. While conventional hematological and imaging tests are adept at detecting organ-specific toxicities, distinguishing adverse reactions from those induced by viruses, bacteria, or immune diseases remains a formidable challenge. Consequently, there exists an urgent imperative for reliable biomarkers capable of accurately predicting or diagnosing irAEs. Thus, a thorough review of existing studies on irAEs biomarkers is indispensable. Our review commences by providing a succinct overview of major irAEs, followed by a comprehensive summary of irAEs biomarkers across various dimensions. Furthermore, we delve into innovative methodologies such as machine learning, single-cell RNA sequencing, multiomics analysis, and gut microbiota profiling to identify novel, robust biomarkers that can facilitate precise irAEs diagnosis or prediction. Lastly, this review furnishes a concise exposition of irAEs mechanisms to augment understanding of irAEs prediction, diagnosis, and treatment strategies.

The advent of immune checkpoint inhibitors (ICIs) has revolutionized the treatment landscape for various malignancies by harnessing the body's immune system to target cancer cells. However, their widespread use has unveiled a spectrum of immune-related adverse events, highlighting a critical balance between antitumor immunity and autoimmunity. This review article delves into the molecular immunology of ICIs, mapping the journey from their therapeutic action to the unintended induction of immune-related adverse events. We provide a comprehensive overview of all available ICIs, including cytotoxic T-lymphocyte-associated protein 4, programmed cell death protein 1, programmed death-ligand 1 inhibitors, and emerging targets, discussing their mechanisms of action, clinical applications, and the molecular underpinnings of associated immune-related adverse events. Special attention is given to the activation of autoreactive T cells, B cells, cytokine release, and the inflammatory cascade, which together contribute to the development of immune-related adverse events. Through a molecular lens, we explore the clinical manifestations of immune-related adverse events across organ systems, offering insights into diagnosis, management, and strategies to mitigate these adverse effects. The review underscores the importance of understanding the delicate interplay between enhancing antitumor responses and minimizing immune-related adverse events, aiming to guide future research and the development of next-generation ICIs with improved drug safety profiles.

Metabolomics has the characteristics of terminal effects and reflects the physiological state of biological diseases more directly. Several current biomarkers of multiple omics were revealed to be associated with immune-related adverse events (irAEs) occurrence. However, there is a lack of reliable metabolic biomarkers to predict irAEs. This study aims to explore the potential metabolic biomarkers to predict risk of irAEs and to investigate the association of plasma metabolites level with survival in patients with lung cancer receiving PD-1/PD-L1 inhibitor treatment.

The study collected 170 plasmas of 85 patients with lung cancer who received immune checkpoint inhibitors (ICIs) treatment. 58 plasma samples of 29 patients with irAEs were collected before ICIs treatment and at the onset of irAEs. 112 plasma samples of 56 patients who did not develop irAEs were collected before ICIs treatment and plasma matched by treatment cycles to onset of irAEs patients. Untargeted metabolomics analysis was used to identify the differential metabolites before initiating ICIs treatment and during the process that development of irAEs. Kaplan-Meier curves analysis was used to detect the associations of plasma metabolites level with survival of patients with lung cancer.

A total of 24 differential metabolites were identified to predict the occurrence of irAEs. Baseline acylcarnitines and steroids levels are significantly higher in patients with irAEs, and the model of eight acylcarnitine and six steroid metabolites baseline level predicts irAEs occurrence with area under the curve of 0.91. Patients with lower concentration of baseline decenoylcarnitine(AcCa(10:1) 2, decenoylcarnitine(AcCa(10:1) 3 and hexanoylcarnitine(AcCa(6:0) in plasma would have better overall survival (OS). Moreover, 52 differential metabolites were identified related to irAEs during ICIs treatment, dehydroepiandrosterone sulfate, corticoserone, cortisol, thyroxine and sphinganine 1-phaosphate were significantly decreased in irAEs group while oxoglutaric acid and taurocholic acid were significantly increased in irAEs group.

High levels of acylcarnitines and steroid hormone metabolites might be risk factor to development of irAEs, and levels of decenoylcarnitine (AcCa(10:1) 2, decenoylcarnitine (AcCa(10:1) 3 and hexanoylcarnitine (AcCa(6:0) could be used to predict OS for patients with lung cancer received ICIs treatment.

Immune checkpoint inhibitors (ICIs) including anti-programmed death cell protein 1 (anti-PD1) and anti-programmed cell death-ligand 1 (PD-L1), by disinhibiting the antitumor responses of lymphocytes, have extended survival benefits for patients in lung cancer. ICIs can also lead to a wide spectrum of immune-related adverse events (irAEs), due to dysregulation of immune reactions. Here, we report a 27-year-old female patient with adenocarcinoma of the lung treated with pembrolizumab-combined chemotherapy treatment, who complained of urinary irritation symptoms. No bacteria were found in multiple urine cultures. B-mode ultrasonography indicated a high echo in the right lateral wall of the bladder, about 5.6 × 4.5 mm in size. Transurethral bladder tumor resection (TURBT) was operated. At biopsy, we found CD3+ CD8+ lymphocyte, plasma cell, and eosinophil infiltration and lymphoid follicle formation in the bladder mucosal layer. This is a report of non-bacterial inflammation of the urinary tract caused by immunotherapy.

Recombinant antibodies (Abs) are an integral modality for the treatment of multiple tumour malignancies. Since the Food and Drug Administration (FDA) approval of rituximab as the first monoclonal antibody (mAb) for cancer treatment, several mAbs and antibody (Ab)-based therapies have been approved for the treatment of solid tumour malignancies and other cancers. These Abs function by either blocking oncogenic pathways or angiogenesis, modulating immune response, or by delivering a conjugated drug. The use of Ab-based therapy in cancer patients who could benefit from the treatment, however, is still limited by associated toxicity profiles which may stem from biological features and processes related to target binding, alongside biochemical and/or biophysical characteristics of the therapeutic Ab. A significant immune-related adverse event (irAE) associated with Ab-based therapies is cytokine release syndrome (CRS), characterized by the development of fever, rash and even marked, life-threatening hypotension, and acute inflammation with secondary to systemic uncontrolled increase in a range of pro-inflammatory cytokines. Here, we review irAEs associated with specific classes of approved, Ab-based novel cancer immunotherapeutics, namely immune checkpoint (IC)-targeting Abs, bispecific Abs (BsAbs) and Ab-drug-conjugates (ADCs), highlighting the significance of harmonization in preclinical assay development for safety assessment of Ab-based biotherapeutics as an approach to support and refine clinical translation.

Cutaneous immune-related adverse events (cirAEs) are the most common toxicities to occur in the setting of immune checkpoint inhibitor (ICI) therapy. Identifying patients who are at increased risk of developing cirAEs may improve quality of life and outcomes.

To investigate the influence of cancer type and histology on the development of cirAEs in the setting of ICI therapy and survival outcomes.

This retrospective cohort study included patients recruited between 1 December 2011 and 30 October 2020. They received ICI from 2011 to 2020 with follow-up of outcomes through October 2021. We identified 3668 recipients of ICI therapy who were seen at Massachusetts General Brigham and Dana-Farber. Of these, 669 developed cirAEs. Records that were incomplete or categories of insufficient sample size were excluded from the study cohort. Multivariate Cox proportional hazards models were used to investigate the impact of cancer organ system and histology on cirAE development, after adjusting for demographics, Charlson Comorbidity Index, ICI type, cancer stage at ICI initiation, and year of ICI initiation. Time-varying Cox proportional hazards modelling was used to examine the impact of cirAE development on mortality.

Compared with other nonepithelial cancers (neuroendocrine, leukaemia, lymphoma, myeloma, sarcoma and central nervous system malignancies), cutaneous squamous cell carcinoma [cSCC; hazard ratio (HR) 3.57, P < 0.001], melanoma (HR 2.09, P < 0.001), head and neck adenocarcinoma (HR 2.13, P = 0.009), genitourinary transitional cell carcinoma (HR 2.15, P < 0.001) and genitourinary adenocarcinoma (HR 1.53, P = 0.037) were at significantly higher risk of cirAEs in multivariate analyses. The increased risk of cirAEs translated into an adjusted survival benefit for melanoma (HR 0.37, P < 0.001) and cSCC (HR 0.51, P = 0.011).

The highest rate of cirAEs and subsequent survival benefits were observed in cutaneous malignancies treated with ICI therapies. This study improves our understanding of patients who are at highest risk of developing cirAEs and would, therefore, benefit from appropriate counselling and closer monitoring by their oncologists and dermatologists throughout their ICI therapy. Limitations include its retrospective nature and cohort from one geography.

Aim: Inherent variations in human leukocyte antigen (HLA) alleles have been revealed epidemiologically to influence the development of autoimmune diseases. HLA alleles may thus also be associated with the development of immune-related adverse events (irAEs), such as thyroid irAE.Materials & methods: In this case-control study, 71 cancer patients who received immune checkpoint inhibitors were enrolled and HLA-genotyped and the frequency of HLA alleles was compared.Results: A*26:01, DPA1*01:03 and DPB1*02:01 were significantly more frequent in patients with thyroid irAE than in patients without any irAEs (35.0 vs 3.2% [p = 0.004], 80.0 vs 45.2% [p = 0.020] and 55.0 vs 25.8% [p = 0.044], respectively).Conclusion: A*26:01, DPA1*01:03 and DPB1*02:01 appear to be associated with thyroid irAE.

The use of immune checkpoint inhibitors (ICIs) for the treatment of various advanced and aggressive types of malignancy has significantly increased both survival and long-term remission rates. ICIs block crucial inhibitory pathways of the immune system, in order to trigger an aggravated immune response against the tumor. However, this enhanced immune activation leads to the development of numerous immune-related adverse events (irAEs), which may affect any system. Although severe neurological irAEs are relatively rare, they carry a high disability burden, and they can be potentially life-threatening. Therefore, clinicians must be alert and act promptly when individuals receiving ICIs present with new-onset neurological symptoms. In this narrative review, we have collected all the currently available data regarding the epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment of post-ICI neurological irAEs. This review aims to raise physicians' awareness, enrich their knowledge regarding disease pathogenesis, and guide them through the diagnosis and management of post-ICI neurological irAEs.

Recently, antitumor immunotherapies have witnessed a breakthrough with the emergence of immune checkpoint inhibitors (ICIs) including programmed cell death-1 (PD-1), programmed cell death-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors. Unfortunately, the use of ICIs has also led to the advent of a novel class of adverse events that differ from those of classic chemotherapeutics and are more reminiscent of autoimmune diseases, the immune-related adverse events (IRAEs). Herein, we performed an insight of the main IRAEs associated with ICIs, focusing on gastroenterological IRAEs and specifically on checkpoint inhibitor colitis, which represents the most widely reported IRAE to date. We comprehensively dissected the current evidence regarding pathogenesis, diagnosis, and management of ICIs-induced colitis, touching upon also on innovative therapies.

The introduction of immune checkpoint inhibitors (ICIs) has transformed the management of various malignancies. Alongside their therapeutic success, the widespread application of ICIs has unveiled a spectrum of immune-related adverse events (irAEs), most often affecting the skin. Cutaneous irAEs (cirAEs) encompass a range from common morbilliform and lichenoid rashes to more severe conditions such as bullous dermatoses and psoriasiform eruptions, each presenting distinct clinical challenges. Moreover, less common but clinically severe cutaneous reactions like toxic epidermal necrolysis have also been observed. cirAEs are frequently observed, with an incidence ranging from 37% to 70% for anti-cytotoxic T lymphocyte-associated antigen-4 antibodies and 17% to 40% for anti- programmed death-1/anti-programmed death ligand-1 antibodies. Recognizing the critical need for effective therapeutic strategies, this review carefully examines current approaches and guidelines for managing cirAEs.

With their groundbreaking clinical responses, immune checkpoint inhibitors (ICIs) have ushered in a new chapter in cancer therapeutics. However, they are often associated with life-threatening or organ-threatening autoimmune/autoinflammatory phenomena, collectively termed immune-related adverse events (irAEs). In this review, we will first describe the mechanisms of action of ICIs as well as irAEs. Next, we will review biomarkers for predicting the development of irAEs or stratifying risks.

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.

Although immune checkpoint inhibitors have greatly improved cancer therapy, they also cause immune-related adverse events, including a wide range of inflammatory side effects resulting from excessive immune activation. Types of immune-related adverse events are diverse and can occur in almost any organ, with different frequencies and severities. Furthermore, immune-related adverse events may occur within the first few weeks after treatment or even several months after treatment discontinuation. Predictive biomarkers include blood cell counts and cell surface markers, serum proteins, autoantibodies, cytokines/chemokines, germline genetic variations and gene expression profiles, human leukocyte antigen genotype, microRNAs and the gut microbiome. Given the inconsistencies in research results and limited practical utility, there is to date no established biomarker that can be used in routine clinical practice, and additional investigations are essential to demonstrate efficacy and subsequently facilitate integration into routine clinical use.

The development of the immune checkpoint inhibitors (ICI) is one of the most remarkable achievements in cancer therapy in recent years. However, their exponential use has led to an increase in immune-related adverse events (irAEs). Gastrointestinal and liver events encompass hepatitis, colitis and upper digestive tract symptoms accounting for the most common irAEs, with incidence rates varying from 2% to 40%, the latter in patients undergoing combined ICIs therapy. Based on the current scientific evidence derived from both randomized clinical trials and real-world studies, this statement document provides recommendations on the diagnosis, treatment and prognosis of the gastrointestinal and hepatic ICI-induced adverse events.

With immune checkpoint inhibitors (ICIs) becoming the mainstay of treatment for many cancers, managing their immune-related adverse events (irAEs) has become an important part of oncological care. This Review covers the clinical presentation of irAEs and crucial aspects of reversibility, fatality and long-term sequelae, with special attention to irAEs in specific patient populations, such as those with autoimmune diseases. In addition, the genetic basis of irAEs, along with cellular and humoral responses to ICI therapy, are discussed. Detrimental effects of empirically used high-dose steroids and second-line immunosuppression, including impaired ICI effectiveness, call for more tailored irAE-treatment strategies. We discuss open therapeutic challenges and propose potential avenues to accelerate personalized management strategies and optimize outcomes.

The emergence of immune checkpoint inhibitors (ICIs) has heralded a transformative era in the therapeutic landscape of non-small cell lung cancer (NSCLC). While ICIs have demonstrated clinical efficacy in a portion of patients with NSCLC, these treatments concurrently precipitate a spectrum of immune-related adverse events (irAEs), encompassing mild to severe manifestations, collectively posing a risk of significant organ damage. Consequently, there exists an imperative to augment our comprehension of the pathophysiological underpinnings of irAEs and to formulate more efficacious preventive and ameliorative strategies. In this comprehensive review, we delineate the clinical presentation of organ-specific irAEs in patients with NSCLC and provide an in-depth analysis of recent advancements in understanding the mechanisms driving ICI-induced toxicity. Furthermore, we discuss potential strategies and targets for ameliorating these irAEs. Ultimately, this review aims to furnish valuable insights to guide further research endeavours in the context of irAEs in NSCLC patients.

Immune-checkpoint inhibitor-mediated colitis (IMC) is an increasingly recognized adverse event in cancer immunotherapy, particularly associated with immune checkpoint inhibitors (ICIs) such as anti-cytotoxic T-lymphocyte antigen-4 and anti-programmed cell death protein-1 antibodies. As this revolutionary immunotherapy gains prominence in cancer treatment, understanding, diagnosing, and effectively managing IMC becomes paramount. IMC represents a unique challenge due to its immune-mediated nature and potential for severe complications. However, a precise picture of IMC pathophysiology is currently unavailable. Therefore, we aimed to summarize the existing data while acknowledging the need for further research. This comprehensive review explores the mechanisms underlying ICIs, gastrointestinal adverse effects, and, in particular, IMC's incidence, prevalence, and features. Our review also emphasizes the importance of recognizing IMC's distinct clinical and histopathological features to differentiate it from other forms of colitis. Furthermore, this paper highlights the urgent need for evolving diagnostic methods, therapeutic strategies, and a multidisciplinary approach to effectively manage IMC.

Immune checkpoint inhibitors are frequently associated with the development of immunotherapy-related adverse events (irAEs). The exact etiology, including the role of environmental factors, remains incompletely understood.

We analyzed the records of 394 melanoma patients from three centers (northern and southern hemisphere). Patients had received at least one cycle of anti-PD-1/anti-CTLA-4 with a minimum follow-up of 3 months. We study the distribution and time to irAEs onset throughout the calendar year.

764 irAEs were recorded; the most frequent were skin rash (35%), hepatitis (32%) and colitis (30%). The irAEs incidence was the highest in autumn and winter, and the ratio for the 'number of irAEs' per 'therapies commenced' was the highest in winter and lowest in summer (2.4 and 1.7, respectively). Season-specific patterns in the time of irAEs onset were observed for pneumonitis (shorter time to onset in autumn, p = 0.025), hepatitis (shorter time to onset in spring, p = 0.016) and sarcoid-like immune reaction (shorter time to onset in autumn, p = 0.041). Season-specific patterns for early-onset irAEs were observed for hepatitis (spring, p = 0.023) and nephritis (summer, p = 0.017). Early-onset pneumonitis was more frequent in autumn-winter (p = 0.008) and early-onset nephritis in spring-summer (p = 0.004).

Environmental factors that are associated with particular seasons may contribute to the development of certain irAEs and suggest the potential effect of environmental triggers. The identification of these factors may enhance preventive and therapeutic strategies to reduce the morbidity of irAEs.

The development of the immune checkpoint inhibitors (ICI) is one of the most remarkable achievements in cancer therapy in recent years. However, their exponential use has led to an increase in immune-related adverse events (irAEs). Gastrointestinal and liver events encompass hepatitis, colitis and upper digestive tract symptoms accounting for the most common irAEs, with incidence rates varying from 2 % to 40 %, the latter in patients undergoing combined ICIs therapy. Based on the current scientific evidence derived from both randomized clinical trials and real-world studies, this statement document provides recommendations on the diagnosis, treatment and prognosis of the gastrointestinal and hepatic ICI-induced adverse events.

The success of immunotherapy has made it a lifesaving treatment, but not without side effects. Currently, the risk factors for developing immune-related adverse events (irAEs) in patients who receive immunotherapy are poorly understood, and there is no risk-stratifying mechanism for potentially fatal irAEs. It is postulated that oncology patients with preexisting autoimmune diseases are likely to have flares on immunotherapy. However, some patients develop de novo autoimmune conditions on immunotherapy without a prior history. Literature reports have postulated that human leukocyte antigen (HLA) inherence may play a role in irAEs. However, this potential remains underexplored.

The oncology patients who developed autoimmune adverse events on immunotherapy for whom the continuation of treatment was prudent or lifesaving were selected. Of note, all nine patients received checkpoint inhibitors (CIs). Of the nine selected patients, only one had a prior history of an autoimmune condition. None of the nine selected patients had an active autoimmune condition at the time of CI initiation. Their HLA was typed, and the results were cross-referenced with the literature reports in PubMed and Google search with the corresponding autoimmune condition of each patient.

Herein, we report nine patients with irAEs for whom retrospective HLA typing revealed the inherence of multiple related HLA alleles that may correspond to the autoimmune condition that they had developed on immunotherapy. It is to be mentioned that the inherence of enriched disease-related HLA alleles was shared among patients with the same irAEs. These patients developed a range of irAEs including bullous pemphigoid, pemphigus foliaceus/vulgaris, thyroiditis, vitiligo, and hepatitis on immunotherapy. Although some combinations of disease-related HLA were well reported in otherwise idiopathic autoimmune diseases, a frequently repeated HLA allele combination in our patient population was found to be rarely seen in the general population.

The authors suggest that an enriched inherence of disease-related HLA alleles may play a role in the genetic propensity for the development of irAEs in oncology patients, who receive immunotherapy, including CIs. Inherence of more than one or a cluster of particular autoimmune disease-related HLA alleles in patients who receive immunotherapy may unmask the corresponding autoimmune disease as the genotype inherence presents with the phenotype of the corresponding condition. It is suggested that enriched linked HLA genotypes, which are otherwise rare in the general population, may present as the corresponding phenotype of the autoimmune condition. Such clinical presentation, enhanced by immunotherapy, such as CIs, can play a role in risk stratifying patients for precision medicine and improve the outcome.

Immune checkpoint inhibitors (ICI) are important treatment options for metastatic non-small cell lung cancer (mNSCLC). However, not all patients benefit from ICIs and can experience immune-related adverse events (irAEs). Limited understanding exists for germline determinants of ICI efficacy and toxicity, but Human Leukocyte Antigen (HLA) genes have emerged as a potential predictive biomarker. We performed HLA typing on 85 patients with mNSCLC, on ICI therapy and analyzed the impact of HLA Class II genotype on progression free survival (PFS), overall survival (OS), and irAEs. Most patients received pembrolizumab (83.5%). HLA-DRB4 genotype was seen in 34/85 (40%) and its presence correlated with improved OS in both univariate (p = 0.022; 26.3 months vs 10.2 months) and multivariate analysis (p = 0.011, HR 0.49, 95% CI [0.29, 0.85]). PFS did not reach significance (univariate, p = 0.12, 8.2 months vs 5.1 months). Eleven patients developed endocrine irAEs. HLA-DRB4 was the predominant genotype among these patients (9/11, 81.8%). Cumulative incidence of endocrine irAEs was higher in patients with HLA-DRB4 (p = 0.0139). Our study is the first to suggest that patients with metastatic NSCLC patients on ICI therapy with HLA-DRB4 genotype experience improved survival outcomes. Patients with HLA-DRB4 had the longest median OS (26.3 months). Additionally, we found a correlation between HLA-DRB4 and the occurrence of endocrine irAEs.

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.

The development of immune checkpoint inhibitors (ICIs) has a tremendous effect on the treatment options for multiple types of cancer. Nonetheless, there is a large interpatient variability in response, survival, and the development of immune-related adverse events (irAEs). Pharmacogenetics is the general term for germline genetic variations, which may cause the observed interindividual differences in response or toxicity to treatment. These genetic variations can either be single-nucleotide polymorphisms (SNPs) or structural variants, such as gene deletions, amplifications or rearrangements. For ICIs, pharmacogenetic variation in the human leukocyte antigen molecules has also been studied with regard to treatment outcome. This review presents a summary of the literature regarding the pharmacogenetics of ICI treatment, discusses the most important known genetic variations and offers recommendations on the application of pharmacogenetics for ICI treatment.

Immune checkpoint inhibitor (ICI) treatment has been linked to a variety of immune-related adverse events (irAEs), which can affect any organ system. The incidence and risk factors of irAEs have not been adequately evaluated among older adults with NSCLC.

A cohort study was conducted using 1999-2019 SEER-Medicare data among beneficiaries aged ≥65 years with a diagnosis of NSCLC who received nivolumab, pembrolizumab, or atezolizumab. Incident irAEs were identified post-ICI initiation. Demographic, cancer-related characteristics, and clinical history risk factors of irAEs were evaluated with competing events considered.

A total of 8175 older NSCLC patients were included (with 46.8% experiencing irAEs). Pneumonitis (16.5%), hypothyroidism (10.5%), arrhythmia (11.18%), and acute kidney injury (AKI) (5.8%) were the most common irAEs. The median time to first irAE was 82 days (IQR: 29-182 days). The earliest onset of irAE occurrence was for hematologic irAEs, while the latest were gastrointestinal, dermatologic, and musculoskeletal irAEs. Fine-Gray regression modeling revealed significantly greater hazards of irAE occurrence in patients who received pembrolizumab at index, did not have CNS metastases, had a history of autoimmune disorder, and had chemotherapy in combination with ICI. Race, socioeconomic status, previous radiation therapy, and comorbidity burden were found to be associated with the occurrence of certain type of irAEs.

A significant proportion of older patients with NSCLC develop an irAE after receiving ICI treatment. Factors related to cancer and treatment as well as demographics contribute to the increased risk of irAEs. Close monitoring and prediction of irAE among older patients receiving ICI is warranted.

To overcome the epidemiological severity of cancer, developing effective treatments is urgently required. In response, immune checkpoint inhibitors (ICIs) have been revealed as a promising resolution for treatment-resistant cancers across the world. Yet, they have both advantages and disadvantages, bringing therapeutic benefits while simultaneously inducing toxicity, and in particular, immune-mediated adverse drug reactions (imADRs), to the human body. These imADRs can be pathogenic and sometimes lethal, hampering health prediction and monitoring following the provision of ICI treatment. Therefore, it is necessary to collectively identify the determinant factors that contribute to these imADRs induced by ICIs. This article evaluated treatment-, tumor-, and patient-related determinants, and indicated a research gap for future investigations on the pathogenic mechanism of imADRs and translational conversion of determinants into clinical biomarkers to aid pharmacovigilance and cancer therapies.

Immune-checkpoint inhibitors (ICIs), different from traditional cancer treatment models, have shown unprecedented anti-tumor effects in the past decade, greatly improving the prognosis of many malignant tumors in clinical practice. At present, the most widely used ICIs in clinical immunotherapy for a variety of solid tumors are monoclonal antibodies against cytotoxic T lymphocyte antigen-4 (CTLA-4), programmed cell death protein 1 (PD-1) and their ligand PD-L1. However, tumor patients may induce immune-related adverse events (irAEs) while performing immunotherapy, and irAE is an obstacle to the prospect of ICI treatment. IrAE is a non-specific disease caused by immune system imbalance, which can occur in many tissues and organs. For example, skin, gastrointestinal tract, endocrine system and lung. Although the exact mechanism is not completely clear, related studies have shown that irAE may develop through many ways. Such as excessive activation of autoreactive T cells, excessive release of inflammatory cytokines, elevated levels of autoantibodies, and common antigens between tumors and normal tissues. Considering that the occurrence of severe IrAE not only causes irreversible damage to the patient's body, but also terminates immunotherapy due to immune intolerance. Therefore, accurate identification and screening of sensitive markers of irAE are the main beneficiaries of ICI treatment. Additionally, irAEs usually require specific management, the most common of which are steroids and immunomodulatory therapies. This review aims to summarize the current biomarkers for predicting irAE in gastric cancer and their possible mechanisms.