Nivolumab-induced anti-aminoacyl-tRNA synthetase antibody-positive polymyositis complicated by interstitial pneumonia in a patient with lung adenocarcinoma

Immune Checkpoint Inhibitor Related Rheumatological Complications: Cooperation between Rheumatologists and Oncologists

In cancer, immune checkpoint inhibitors (ICIs) improve patient survival but may lead to severe immune-related adverse events (irAEs). Rheumatic irAEs are a distinct entity that are much more common in a real-life than in clinical trial reports due to their unspecific symptoms and them being a rare cause of hospitalization. This review focuses on an interdisciplinary approach to the management of rheumatic irAEs, including cooperation between oncologists, rheumatologists, and immunologists. We discuss the immunological background of rheumatic irAEs, as well as their unique clinical characteristics, differentiation from other irAEs, and treatment strategies. Importantly, steroids are not the basis of therapy, and nonsteroidal anti-inflammatory drugs should be administered in the front line with other antirheumatic agents. We also address whether patients with pre-existing rheumatic autoimmune diseases can receive ICIs and how antirheumatic agents can interfere with ICIs. Interestingly, there is a preclinical rationale for combining ICIs with immunosuppressants, particularly tumor necrosis factor α and interleukin 6 inhibitors. Regardless of the data, the mainstay in managing irAEs is interdisciplinary cooperation between oncologists and other medical specialties.

Immune checkpoint inhibitor-related pneumonitis with atypical radiologic features in a patient with anti-aminoacyl-tRNA synthetase antibody

A man with non-small-cell lung cancer who was negative for anti-nuclear antibodies was admitted for dyspnea after immune checkpoint inhibitor (ICI) administration. Computed tomography (CT) showed complexed radiologic features, including subpleural and basal predominant reticular shadow with cystic structures and peribronchovascular consolidation. Although we treated him with high-dose steroid under a diagnosis of ICI-related pneumonitis, he developed acute exacerbation of pneumonitis with progressive fibrosis and volume loss. A re-evaluation identified anti-aminoacyl-tRNA synthetase antibody in the serum collected before ICI administration. This case highlights the importance of re-evaluating pre-existing autoimmune disorders in patients who develop ICI-related pneumonitis with atypical radiologic features.

Lung cancer and combined pulmonary fibrosis and emphysema with anti-ARS antibody

A 59-year-old man who had smoked for 23 pack-years was admitted to our hospital because of two-month history of back pain. The chest computed tomography scan demonstrated combined pulmonary fibrosis and emphysema (CPFE) and an irregular shaped nodule in the left lower lobe of the lung. A biopsy obtained from samples from subcarinal lymph nodes revealed non-small cell lung cancer. Anti-aminoacyl-tRNA synthetase (ARS) antibody was elevated up to 166 U/mL, although he had no symptoms suggestive connective tissue diseases. It is well known that most of CPFE patients are current or former heavy smokers, and some researchers described the relationship between CPFE and connective tissue diseases. To our best knowledge, this was the first report of lung cancer in patient with anti-ARS antibody-positive CPFE. In some anti-ARS antibody-positive patients, smoking might have a relationship with development of CPFE and lung cancer.

Incidence and Distinct Features of Immune Checkpoint Inhibitor-Related Myositis From Idiopathic Inflammatory Myositis: A Single-Center Experience With Systematic Literature Review and Meta-Analysis

Immune checkpoint inhibitor (ICI)-related myositis is a rare, potentially fatal condition that warrants further studies. Its incidence, clinical features, and prognosis remain poorly understood. To address these gaps, we conducted a systematic review and meta-analysis to evaluate the risk of myositis associated with ICI for solid tumors by analyzing phase III randomized controlled trials of anti-programmed death-1/ligand-1 (PD-1/PD-L1) and anti-cytotoxic T-lymphocyte antigen-4 (CTLA-4). To complement this analysis with clinical data, we evaluated published ICI case reports along with cases from our institutional registry. This registry comprised 422 patients treated with ICIs alone or in combination from September 2014 to June 2021. The analysis revealed an incidence of ICI-related myositis in 6,838 patients in 18 randomized controlled trials of 0.38% (odds ratio 1.96; 95% confidence interval 1.02–3.75) for patients receiving ICIs compared with controls. Detailed analysis of 88 cases from the literature search and our registry showed that myositis induced by PD-1 inhibitors was more frequent than that induced by anti-CTLA-4 agents, revealing a clinically diverse trend including myasthenia gravis and myocarditis. Importantly, having ptosis at the time of onset was significantly associated with the development of concomitant myocarditis (odds ratio 3.81; 95% CI 1.48–9.83), which is associated with poor prognosis. Regarding treatment, most patients received glucocorticoids, and some received immunosuppressants. Our study revealed the incidence of ICI-mediated myositis and the clinical features of myocarditis, highlighting the need for recognition and early intervention.

Case Report: The Neuromusclar Triad of Immune Checkpoint Inhibitors: A Case Report of Myositis, Myocarditis, and Myasthenia Gravis Overlap Following Toripalimab Treatment

The neuromuscular adverse events of immune checkpoint inhibitor (ICI) treatment include myositis, polymyalgia rheumatica, myocarditis, and myasthenia syndrome. We report a 47-year old female presenting with external ophthalmoplegia, generalized muscle weakness, and third-degree atrioventricular block 4 weeks after toripalimab treatment for metastatic thymoma. Creatine kinase was elevated to 25,200 U/l and cardiac troponin I to 2.796 ng/ml. Autoantibody profiling shows positive anti-ryanodine receptor and anti-acetylcholine receptor antibodies and negative myositis specific antibodies. Repetitive nerve stimulation did not reveal decrement of compound muscle action potentials. Pulse methylprednisolone and immunoglobulin infusion, together with temporary pacemaker insertion normalized her muscle enzyme levels and cardiac rhythm. This is the first report of overlaping neuromuscular adverse event of toripalimab.

Management of rheumatic complications of immune checkpoint inhibitor therapy - an oncological perspective

Immune checkpoint inhibitors (CPIs) are an effective treatment for many cancers but cause diverse immune-related adverse events (IrAEs). Rheumatological IrAEs include arthralgia, arthritis, tenosynovitis, myositis, polymyalgia rheumatica and sicca syndrome. CPI use can unmask RA as well as causing flares of prior autoimmune or connective tissue disease. Oncologists categorize and grade IrAEs using the Common Terminology Criteria for Adverse Events and manage them according to international guidelines. However, rheumatological events are unfamiliar territory: oncologists need to work with rheumatologists to elicit and assess symptoms, signs, results of imaging and autoantibody testing and to determine the use of steroids and DMARDs. Myositis may overlap with myasthenic crisis and myocarditis and can be life-threatening. Treatment should be offered on balance of risk and benefit, including whether to continue CPI treatment and recognizing the uncertainty over whether glucocorticoids and DMARDs might compromise cancer control.