Management of rheumatic complications of ICI therapy: a rheumatology viewpoint

Immune-related adverse events of anti-PD-1 immune checkpoint inhibitors: a single center experience

Objectives

Immune checkpoint inhibitors (ICIs) stimulate antitumor immune responses and, in parallel, they might trigger autoimmune and other immunopathological mechanisms eventually leading to immune-related adverse events (irAE). In our study, we assessed patients with malignancies who underwent anti-PD-1 treatment at the University of Debrecen, Clinical Center.

Patients and methods

Between June 2017 and May 2021, 207 patients started ICI treatment at our university. A total of 157 patients received nivolumab and 50 were treated with pembrolizumab. We looked for factors associated with the development of irAEs. In addition to correlation studies, we performed binary logistic regression analysis to determine, which factors were associated with irAEs. We also performed Forward Likelihood Ratio (LR) analysis to determine independent prognostic factors.

Results

At the time of data analysis, the mean duration of treatment was 2.03 ± 0.69 years. ROC analysis determined that 9 or more treatment cycles were associated with a significantly higher risk of irAEs. A total of 125 patients received ≥9 treatment cycles. Three times more patients were treated with nivolumab than pembrolizumab. Of the 207 patients, 66 (32%) developed irAEs. Among the 66 patients who developed irAEs, 36 patients (55%) developed one, 23 (35%) developed two, while 7 (10%) developed three irAEs in the same patient. The most common irAEs were thyroid (33 cases), dermatological (25 cases), pneumonia (14 cases) and gastrointestinal complications (13 cases). Patients who developed irAEs received significantly more treatment cycles (21.8 ± 18.7 versus 15.8 ± 17.4; p=0.002) and were younger at the start of treatment (60.7 ± 10.8 versus 63.4 ± 10.1 years; p=0.042) compared to patients without irAEs. Pembrolizumab-treated patients developed more but less severe irAEs compared to those receiving nivolumab.

Conclusion

ICI treatment is very effective, however, irAEs may develop. These irAEs might be related to the number of treatment cycles and the type of treated malignancy.

Sex and anti-inflammatory treatment affect outcome of melanoma and non-small cell lung cancer patients with rheumatic immune-related adverse events

BACKGROUND

Rheumatic immune-related adverse events (R-irAEs) occur in 5-15% of patients receiving immune checkpoint inhibitors (ICI) and, unlike other irAEs, tend to be chronic. Herein, we investigate the factors influencing cancer and R-irAEs outcomes with particular focus on adverse effects of anti-inflammatory treatment.

METHODS

In this prospective, multicenter, long-term, observational study, R-irAEs were comprehensively analyzed in patients with malignant melanoma (MM, n=50) and non-small cell lung cancer (NSCLC, n=41) receiving ICI therapy who were enrolled in the study between August 1, 2018, and December 11, 2022.

RESULTS

After a median follow-up of 33 months, progressive disease or death occurred in 66.0% and 30.0% of MM and 63.4% and 39.0% of patients with NSCLC. Male sex (progression-free survival (PFS): p=0.013, and overall survival (OS): p=0.009), flare of a pre-existing condition (vs de novo R-irAE, PFS: p=0.010) and in trend maximum glucocorticoid (GC) doses >10 mg and particularly ≥1 mg/kg prednisolone equivalent (sex-adjusted PFS: p=0.056, OS: p=0.051) were associated with worse cancer outcomes. Patients receiving disease-modifying antirheumatic drugs (DMARDs) showed significantly longer PFS (n=14, p=0.011) and OS (n=20, p=0.018). Effects of these variables on PFS and/or OS persisted in adjusted Cox regression models. Additionally, GC treatment negatively correlated with the time from diagnosis of malignancy and the latency from ICI start until R-irAE onset (all p<0.05). R-irAE features and outcomes were independent of other baseline patient characteristics in both studied cancer entities.

CONCLUSION

Male sex, flare of pre-existing rheumatologic conditions and extensive GC treatment appeared to be linked with unfavorable cancer outcomes, while DMARD use had a favorable impact. These findings challenge the current dogma of restrictive DMARD use for R-irAE and thus may pave the way to better strategies and randomized controlled trials for the growing number of patients with R-irAE.

Adverse event costs associated with first-line therapy for advanced non-small cell lung cancer in the United States: An analysis of clinical trials of immune checkpoint inhibitors

BACKGROUND: Immune checkpoint inhibitors, such as pembrolizumab, nivolumab, and atezolizumab, have demonstrated substantial survival benefits in patients with advanced non-small cell lung cancer (NSCLC). However, there is limited evidence on their relative safety profiles and adverse event (AE)-related cost burden. OBJECTIVE: To compare the AE management costs of nivolumab plus ipilimumab with and without limited chemotherapy with those of chemotherapy, pembrolizumab plus chemotherapy, and atezolizumab plus chemotherapy in a first-line setting among patients with advanced NSCLC. METHODS: The mean per-patient AE costs were estimated using the incidence of all-cause grade 3/4 AEs with any-grade incidence greater than or equal to 15% and the corresponding costs of AE management in the inpatient setting. AE rates were obtained from individual patient data from the CheckMate 227 and CheckMate 9LA trials for nivolumab plus ipilimumab with/without limited chemotherapy and aggregated data from the KEYNOTE-189 and KEYNOTE-407 trials for pembrolizumab plus chemotherapy and the IMpower130 trial for atezolizumab plus chemotherapy. AE management costs from the third-party payer perspective were estimated based on inpatient medical costs from the 2016 United States Healthcare Cost and Utilization Project National Inpatient Sample. All costs were inflated to 2020 US dollars. RESULTS: Nivolumab plus ipilimumab and nivolumab plus ipilimumab plus limited chemotherapy were associated with lower per-patient grade 3/4 AE costs compared with chemotherapy ($1,708 and $624 lower over the treatment course, respectively). Compared with pembrolizumab plus chemotherapy, nivolumab plus ipilimumab was associated with lower grade 3/4 AE costs in patients with nonsquamous histology (difference: -$4,866) and squamous histology (difference: -$3,795), and nivolumab plus ipilimumab with limited chemotherapy also had lower AE costs for both nonsquamous (difference: -$2,800) and squamous (difference: -$2,753) disease. Similarly, nivolumab plus ipilimumab and nivolumab plus ipilimumab plus limited chemotherapy were also associated with lower AE costs ($11,400 and $8,809 lower, respectively) compared with atezolizumab plus chemotherapy among patients with nonsquamous disease. In particular, nivolumab plus ipilimumab without or with limited chemotherapy were associated with much lower AE costs of hematological AEs compared with chemotherapy and other immune checkpoint inhibitor-based treatments in combination with a full course of chemotherapy. CONCLUSIONS: Nivolumab plus ipilimumab with/without limited chemotherapy was associated with lower AE management costs compared with chemotherapy, pembrolizumab plus chemotherapy, and atezolizumab plus chemotherapy as first-line treatment for advanced NSCLC. The AE cost benefits were largely driven by the lower cost burden for hematological AEs for nivolumab plus ipilimumab with/without limited chemotherapy. DISCLOSURES This study was supported by Bristol-Myers Squibb. The sponsor was involved in all aspects of the work and in the decision to submit the manuscript for publication. Dr Stenehjem has received consulting fees from Bristol-Myers Squibb. Dr Lubinga was an employee of Bristol-Myers Squibb at the time of the study's conduct and holds stock/options. Drs Betts and Wu are employees of Analysis Group, Inc., a consulting company that has received funding from Bristol-Myers Squibb for this research.

Side Effects of Cancer Immunotherapies: Dermatologic and Rheumatologic Toxicities

Dermatologic and rheumatologic toxicities are frequent adverse events during treatment with immune checkpoint inhibitors in oncology. Timely identification of these events and the referral to the oncologist or dermatologist are important in daily practice, such an organ damage involvements can be severe and sometimes life-threatening. The diagnosis and management of cutaneous toxicities, such as maculopapular rash and bullous dermatitis in particular, must be based on the body surface affected by skin lesions. Corticosteroids are basic treatment in moderate to severe cases. Rheumatologic toxicities are rarer and more heterogeneous, and they are often underestimated. They can occur in the absence of autoantibodies, and myositis can be life-threatening.

Severe treatment-induced inflammatory polyarthritis in advanced melanoma patients: 2 case reports

Immune checkpoint inhibitors (ICI) and targeted therapies form the therapeutic mainstay for v-Raf murine sarcoma viral oncogene homolog B V600-mutated metastatic melanoma. Both treatment regimens can cause inflammatory arthritis. The reported incidence of treatment-induced inflammatory arthritis is low, though presumably underestimated due to lack of awareness, clear definitions and uniform grading systems. Nevertheless, recognition is important as inflammatory arthritis can become chronic and thus affect the quality of life beyond treatment. In this short communication, we present two patients with metastatic melanoma treated with ICI and targeted therapies who develop severe polyarthritis. Based on their clinical discourse we describe standard inflammatory arthritis treatment modalities and more advanced immunomodulatory treatment options with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) or biologic DMARDs (bDMARDs). Long-term immunosuppressive treatment with glucocorticoids or DMARDs in this setting raises concerns about antitumour response and potential carcinogenic risk. Current literature on this topic is scarce, heterogeneous and retrospective. Prospective analysis of cancer patients treated with DMARDs is needed to clearly address these concerns.

Tumor necrosis factor alpha neutralization attenuates immune checkpoint inhibitor-induced activation of intermediate monocytes in synovial fluid mononuclear cells from patients with inflammatory arthritis

Objective

During treatment with immune checkpoint inhibitors (ICI) such as the anti-PD-1 antibody pembrolizumab, half of patients with pre-existing inflammatory arthritis experience disease flares. The underlying immunological mechanisms have not been characterized. Here, we investigate the effect of pembrolizumab on cells involved in inflammation and destruction in the synovial joint and how immunosuppressive treatments affect the pembrolizumab-induced immune reactions.

Methods

We included synovial fluid mononuclear cells (SFMCs, n = 28) and peripheral blood mononuclear cells (PBMCs, n = 6) from patients with rheumatoid arthritis and peripheral spondyloarthritis and PBMCs from healthy controls (n = 6). Fibroblast-like synovial cells (FLSs) were grown from SFMCs. The in vitro effect of pembrolizumab was tested in SFMCs cultured for 48 h, FLS-PBMC co-cultures and in SFMCs cultured for 21 days (inflammatory osteoclastogenesis). Cells and supernatants were analyzed by ELISA, flow cytometry, and pro-inflammatory multiplex assay. Finally, the effect of the disease-modifying anti-rheumatic drugs (DMARDs) adalimumab (TNFα inhibitor), tocilizumab (IL-6R inhibitor), tofacitinib (JAK1/JAK3 inhibitor), and baricitinib (JAK1/JAK2 inhibitor) on pembrolizumab-induced immune reactions was tested.

Results

Pembrolizumab significantly increased monocyte chemoattractant protein-1 (MCP-1) production by arthritis SFMCs (P = 0.0031) but not by PBMCs from patients or healthy controls (P = 0.77 and P = 0.43). Pembrolizumab did not alter MMP-3 production in FLS-PBMC co-cultures (P = 0.76) or TRAP secretion in the inflammatory osteoclastogenesis model (P = 0.28). In SFMCs, pembrolizumab further increased the production of TNFα (P = 0.0110), IFNγ (P = 0.0125), IL-12p70 (P = 0.0014), IL-10 (P = 0.0100), IL-13 (P = 0.0044), IL-2 (P = 0.0066), and IL-4 (P = 0.0008) but did not change the production of IL-6 (P = 0.1938) and IL-1 (P = 0.1022). The SFMCs treated with pembrolizumab showed an increased frequency of intermediate monocytes (P = 0.044), and the MCP-1 production increased only within the intermediate monocyte subset (P = 0.028). Lastly, adalimumab, baricitinib, and tofacitinib treatment were able to attenuate the pembrolizumab-induced MCP-1 production (P = 0.0004, P = 0.033, and P = 0.025, respectively), while this was not seen with tocilizumab treatment (P = 0.75).

Conclusion

Pembrolizumab specifically activated intermediate monocytes and induced the production of several cytokines including TNFα but not IL-6. These findings indicate that flares in patients with pre-existing inflammatory arthritis involve monocyte activation and could be managed with TNFα neutralization.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02737-6.

Rheumatological Adverse Events Following Immunotherapy for Cancer

Background and Objectives: The occurrence of rheumatological side effects in a patient after receiving immunotherapy for cancer is becoming increasingly common. Oncologists often fail to diagnose and refer affected patients to rheumatologists. This paper presents the various rheumatological adverse events that occur after immunotherapy in patients as well as their treatment and evolution. Materials and Methods: A total of 36 patients were monitored between November 2018 and March 2020. The oncologist monitoring the immunotherapy-treated patients identified the occurrence of musculoskeletal side effects. The grading of toxicities was performed by both the oncologist and the rheumatologist using common terminology criteria for adverse events (CTCAE). Rheumatological treatment was administered, and for some patients, immunotherapy was discontinued. Results: The clinical presentations of the patients varied. Mild side effects (grade 1-2) were reported in a higher proportion than severe side effects (grade 3-5). Therefore, thirty-one patients had mild-to-moderate side effects, and five patients had severe side effects. Adverse reactions occurred, on average, 10 weeks after the initiation of immunotherapy; this indicated that the severity of the toxicity was dose dependent. Patients were treated with NSAIDs or prednisone, depending on the severity of the side effects, and for patients with severe manifestations, immunotherapy was discontinued. The remission of rheumatic manifestations varied depending on the grade of the manifestations. Conclusions: The clinical, biological, and ultrasound presentations of the patients with adverse events followed by cancer treatments differed from classic rheumatological manifestations. Thorough examinations of these patients by both oncologists and rheumatologists are needed in order to correctly diagnose and treat rheumatological adverse events. Multiple studies that include a larger number of participants are needed in order to better understand the pathogenesis and clinical evolution of these patients under different treatment conditions.

Rheumatic Manifestations and Diseases From Immune Checkpoint Inhibitors in Cancer Immunotherapy

Immune checkpoint inhibitors (ICIs), which can enhance antitumor immunity and inhibit cancer growth, have revolutionized the treatment of multiple cancers and dramatically decreased mortality. However, treatment with ICIs is directly associated with immune-related adverse events (irAEs) because of inflammation in off-target organs and autoimmunity resulting from non-specific immune activation. These irAEs can cause rheumatic diseases and manifestations such as inflammatory arthritis, polymyalgia rheumatica, myositis, vasculitis, Sicca and Sjogen's syndrome, and systemic lupus erythematosus. Early diagnosis and treatment of these adverse events will improve outcomes and quality of life for cancer patients. The treatment of rheumatic diseases induced by ICIs requires multidisciplinary cooperation among physicians. Furthermore, the underlying mechanisms are not fully understood and it is difficult to predict and evaluate these side effects precisely. In this review, we summarize available studies and findings about rheumatic irAEs, focusing mainly on the clinical manifestations, epidemiology, possible mechanisms, and guiding principles for treating these irAEs.

[Myofasciitis under nivolumab treatment]

We report the case of a 73-year-old female patient with malignant melanoma who developed rapidly progressive dermatosclerosis of the arms and legs as well as myalgia and flexion contractures during treatment with the immune checkpoint inhibitor nivolumab. The diagnosis of a myofasciitis was confirmed by imaging and biopsy. Following consultation with the treating dermato-oncologists nivolumab treatment was paused and treatment with methotrexate and prednisolone was initiated. Immune checkpoint inhibitors can induce a variety of immune-mediated side effects and can also imitate symptoms of rheumatological diseases. The occurrence of myofasciitis under immune checkpoint inhibition has been reported in the literature only in a few cases. Further oncological and rheumatological treatment management should be carried out in close interdisciplinary coordination.

The Role of Immunotherapy in the Treatment of Adrenocortical Carcinoma

Adrenocortical carcinoma (ACC) is a rare epithelial neoplasm, with a high tendency for local invasion and distant metastases, with limited treatment options. Surgical treatment is the method of choice. For decades, the mainstay of pharmacological treatment has been the adrenolytic drug mitotane, in combination with chemotherapy. Immunotherapy is the latest revolution in cancer therapy, however preliminary data with single immune checkpoint inhibitors showed a modest activity in ACC patients. The anti-neoplastic activity of immune checkpoint inhibitors such as anti-cytotoxic-T-lymphocyte-associated-antigen 4 (anti-CTLA-4), anti-programmed death-1 (anti-PD-1), and anti-PD-ligand-1 (PD-L1) antibodies in different solid tumors has aroused interest to explore the potential therapeutic effect in ACC as well. Multiple ongoing clinical trials are currently evaluating the role of immune checkpoint inhibitors in ACC (pembrolizumab, combination pembrolizumab and relacorilant, nivolumab, combination nivolumab and ipilimumab). The primary and acquired resistance to immunotherapy continue to counter treatment efficacy. Therefore, attempts are made to combine therapy: anti-PD-1 antibody and anti-CTLA-4 antibody, anti-PD-1 antibody and antagonist of the glucocorticoid receptor. The inhibitors of immune checkpoints would benefit patients with antitumor immunity activated by radiotherapy. Immunotherapy is well tolerated by patients; the most frequently observed side effects are mild. The most common adverse effects of immunotherapy are skin and gastrointestinal disorders. The most common endocrinopathy during anti-CTLA treatment is pituitary inflammation and thyroid disorders.

Immune manifestations with checkpoint inhibitors in a single Brazilian center: experience and literature review

Objectives

The presence of autoimmune events were recorded in patients receiving immune checkpoint inhibitors.

Materials & Methods

Retrospective study in patients receiving immune checkpoint inhibitors (ICIs) during the period of 2012-2019.

Results

A total of 554 patients received ICIs of which 123 developed an immune related adverse event. Twenty one (17%) with toxicity were identified as having a pre-existing autoimmune disease and 88 required treatment with corticosteroids or hormone replacement. Thirty two (26%) out of 123 had to temporarily discontinue ICIs due to autoimmune manifestations. Endocrine and skin manifestations were the most prevalent immune disorders in our cohort. In melanoma better efficacy was seen in patients with immune toxicity.

Conclusion

Autoimmune diseases appear in patients receiving ICIs in this real world experience. Our results differ from other series on the frequency of autoimmunity. Complete discontinuation of ICIs due to autoimmunity was rare.

Nebenwirkungen immunonkologischer Therapien

Immunonkologische Therapien und insbesondere die Immuncheckpoint-Inhibitoren (ICPi) als Hauptvertreter dieser neuen Substanzklasse kommen bei zunehmender Anzahl von soliden und teils auch hämatologischen Tumorentitäten und Indikationen zum Einsatz. Die relativ hohen (Langzeit-)Tumoransprechraten auch in fortgeschrittenen und therapierefraktären Stadien haben die therapeutischen Möglichkeiten der Onkologie geradezu revolutioniert. Gleichzeitig bringt der zunehmende Einsatz von ICPi auch neue Herausforderungen: Immunonkologische Therapien verursachen ein breites Spektrum an autoimmunen Nebenwirkungen, sogenannten „immune-related adverse events“ (irAEs), die teilweise klassischen Autoimmunopathien ähneln und jedes Organsystem betreffen können. Die große Mehrheit der ICPi-behandelten Patienten erlebt ein irAE an mindestens einem Organsystem und davon weisen ca. 5–20% ein rheumatisches irAEs auf. Diese sind interessanterweise mit einem besseren Tumoransprechraten bei ICPi-Therapie assoziiert und können entweder die Erstmanifestation einer klassischen entzündlich-rheumatischen Erkrankung oder auch nur eine transiente Nebenwirkung mit spezifischen Charakteristika sein. Zweifelsohne wird das interdisziplinäre Management immunvermittelter Nebenwirkungen auch den Rheumatologen in den nächsten Jahren zunehmend beschäftigen. Der vorliegende Artikel fasst die Erkenntnisse zum klinischen Management von irAEs für den praktizierenden Rheumatologen zusammen.

Eight pillars of oncorheumatology: Crossroads between malignancies and musculoskeletal diseases

ONCORHEUMATOLOGY

RELATIONSHIP BETWEEN MALIGNANCIES AND MUSCULOSKELETAL DISEASES: Oncorheumatology is the meeting point of tumor formation and rheumatic musculoskeletal diseases (RMD). Multiple interactions exist between these two medical specialties. One major field is the topic of malignancies associated with rheumatic diseases, while the other topic covers the development of musculoskeletal disease in cancer patients. Within the first group, secondary malignancies may be associated with rheumatic diseases. Mostly sustained inflammation is responsible for transition into cancer. Tumor-associated antigens (TAA) with adhesive properties are present on tumor cells. These molecules may also be expressed by inflammatory leukocytes and soluble TAA levels may be elevated in RMDs. There has been continuous debate with respect to the possible carcinogenicity of conventional and targeted antirheumatic drugs. Very recent data from registries suggest that neither biologics, nor JAK inhibitors increase cancer risk in arthritis patients. The issue of physiotherapy in rheumatic patients with recent or current cancer has also been controversial. Some modalities, primarily exercise, may be safely applied to patients with RMD and cancer. The second large topic includes paraneoplastic syndromes. Musculoskeletal paraneoplasias are triggered by tumor-derived mediators. These syndromes are sometimes slightly different from the classical RMDs. Various chemotherapies may also be associated with autoimmune side effects. Recently, these immune-related complications have also been observed in cancer patients treated with immune-checkpoint inhibitors. Sex hormone-deprivation therapies, such as aromatase inhibitors and anti-androgens are widely used for the treatment of breast and prostate cancer, respectively. These compounds may induce bone loss and lead to osteoporosis. Finally, primary and secondary malignancies of the musculoskeletal system may also interest rheumatologists. In this review, the clinical, practical aspects of these eight pillars of oncorheumatology will be discussed.

Immune checkpoint inhibitor-induced inflammatory arthritis: identification and management

INTRODUCTION

Immune checkpoint inhibitors (ICIs) have proved to be groundbreaking in the field of oncology. However, immune system overactivation from ICIs has introduced a novel medical entity known as immune-related adverse events (irAEs), that can affect any organ or tissue. ICI-induced inflammatory arthritis (ICI-IIA) is the most common musculoskeletal irAE and can lead to significant morbidity and limitation in anti-cancer therapy.

AREAS COVERED

In this review, the authors focus on ICI-IIA. Relevant articles were identified through PubMed searches, spanning 2010 to the present. The authors detail the current understanding of its pathogenesis, diagnostic evaluation, and management strategies.

EXPERT OPINION

ICI-IIA is a complex irAE that we are just beginning to understand mechanistically and pathologically. It often presents later in the disease course than other irAEs and, due to various reasons, is under-recognized. In some patients, ICI-IIA may become a chronic disease, which distinguishes it from most irAEs that resolve after ICI discontinuation. Multiple important questions still demand further research including which patients may develop ICI-IIA? What are possible diagnostic and prognostic markers? Do anti-arthritis therapies interfere with the anti-tumor response? and when should steroid-sparing agents be initiated? Close collaboration and shared decision-making between oncologists, rheumatologists, and the patient are essential when managing this particular irAE.

[Clinical management of rheumatic immune-related adverse events : Recognize and treat rheumatological side effects of checkpoint inhibition]

Immune checkpoint inhibitors (ICPi) represent a major breakthrough in the treatment and prognosis of many cancers, particularly of malignant melanoma and non-small cell lung cancer; however, the high tumor response rates with ICPi are also frequently associated with autoimmune side effects, so-called immune-related adverse events (irAEs), which can involve virtually any organ system and mirror classical autoimmune diseases. Recent studies revealed that around 5-20% of patients treated with ICPi experience rheumatic irAEs covering the full spectrum of inflammatory rheumatic diseases. This article summarizes the state of the art of knowledge with respect to diagnostics and management of this newly recognized disease entity in rheumatology.

Sicca syndrome following immune checkpoint inhibition

The recent approval of Immunologic checkpoint inhibitors as an effective therapeutic strategy against cancer came at the cost of toxicities mediated by an excessive activation of immune system against health tissues, including among others musculoskeletal and sicca complaints.The latter occur in the context of an entity reminiscent of Sjogren's syndrome, with distinct characteristics such as abrupt onset, male predominance, lower prevalence of autoantibodies and response to steroids.

[Side effects of novel cancer immunotherapies]

Systemic treatment with immune checkpoint inhibitors (ICI) has revolutionized the treatment of hematological and oncological diseases in recent years. The mechanism of action hinges on enhancing the natural ability of the immune system to eliminate malignant cells. The most important substances in this arena include inhibitors of PD‑1, PD-L1 and CTLA‑4. As a consequence, the spectrum of treatment-associated adverse reactions is shifting away from classical cytotoxic effects (e.g. pancytopenia and polyneuropathy) towards novel entities of immune-mediated complex diseases. These so-called immune-related adverse events (irAEs) can involve any organ system and mimic known classical autoimmune conditions. Timely recognition of irAEs is the key for rapid initiation of a suitable treatment and is especially challenging in the clinical routine as it requires an intensive interdisciplinary management. Nephrologists are particularly confronted with this kind of problem due to the highly interdisciplinary nature of their work. This article summarizes the broad spectrum of currently known renal and more frequently occuring non-renal forms of irAEs and aims to prime the reader on diagnostic and therapeutic options.

Immune Checkpoint Inhibitor-Related Myositis: From Biology to Bedside

Immune checkpoint inhibitor (ICI)-related inflammatory diseases, including polymyositis (PM) and dermatomyositis (DM), in patients suffering from neoplastic disorders represent a medical challenge. The treatment of these conditions has taken on new urgency due to the successful and broad development of cancer-directed immunological-based therapeutic strategies. While primary and secondary PM/DM phenotypes have been pathophysiologically characterized, a rational, stepwise approach to the treatment of patients with ICI-related disease is lacking. In the absence of high-quality evidence to guide clinical judgment, the available data must be critically assessed. In this literature review, we examine partially neglected immunological and clinical findings to obtain insights into the biological profiles of ICI-related PM/DM and potential treatment options. We show that differential diagnosis is essential to stratifying patients according to prognosis and therapeutic impact. Finally, we provide a comprehensive assessment of druggable targets and suggest a stepwise patient-oriented approach for the treatment of ICI-related PM/DM.