Lethal Immune Myocarditis and Myasthenia Gravis Due to Anti-PD-1 Treatment for a Bladder Cancer Patient: A Case Report and Possible Treatment Inspiration

Abstract: Immune checkpoint inhibitors (ICI) have become a new hope for many patients with advanced cancer by blocking tumor immune escape. Bladder cancer is a common malignant tumor of the urinary tract epithelium that often relapses and metastasizes after surgery, chemotherapy, and radiotherapy. Immunotherapy has dramatically improved patient survival rates and clinical benefits as a new, potentially effective therapy. However, avoidance of various immune-related adverse events (irAEs) remains an implausible idea. ICI-induced myocarditis is different from viral myocarditis, and mortality is still high with the current treatment. We report the case of an 82-year-old female patient with ICI-induced fulminant myocarditis and myasthenia gravis. Although she actively accepted the current mainstream treatment for immune-related myocarditis and myasthenia, she died of heart and respiratory failure. Analyzing and reporting the patient's disease development process and the changes in related indicators may help peers gain a deeper understanding of immune-related adverse events and reduce the mortality of immune-related myocarditis. Keywords: immune checkpoint inhibitors, immunotherapy, heart failure, multiple organs failure