Immune Checkpoint Inhibitor Associated Autoimmune Encephalitis, Rare and Novel Topic of Neuroimmunology: A Case Report and Review of the Literature

Abstract

Immune checkpoint inhibitors (ICIs) are being used in patients with various advanced malignancies, and patient outcomes have improved considerably. Although ICIs can effectively treat tumors, 30–60% of patients experience immune-related adverse events (irAEs). Autoimmune encephalitis (AE) is a rare irAE that has become a novel topic in neuroimmunology and has received increasing attention in recent years. Herein, we report a rare case of GAD65-antibody–associated AE after metastatic small cell lung cancer treatment with pembrolizumab. The patient received IVIg therapy for AE and continuous pembrolizumab therapy without suspension of tumor treatment. At 1 year follow-up, both the patient’s AE symptoms and tumors were stable. We consider that the treatment of ICI-associated AE should be more individualized with prudent decision-making and should balance the tumor progression and AE treatment. In addition, we have also comprehensively reviewed the literature of ICI-associated AE, and summarized the clinical features, treatment, and prognosis of AE caused by ICI, thus broadening our understanding of the neurological complications caused by ICI.

Protective effect of resveratrol against pembrolizumab‐induced hepatotoxicity and neurotoxicity in male rats

“…It has been suggested that further studies are needed in the field of neuroimmunology, the mechanisms, clinical features, and treatment of immune checkpoint inhibitor-associated autoimmune encephalitis. [36] In the present study, similar to liver tissue, PEMB treatment in brain tissue significantly increased TBARS and GSH levels and decreased SOD, CAT, and GPx activities. Based on the results of the evaluation of TBARS levels together with the decreased antioxidant enzyme activity, it can be said that PEMB increases oxidative stress in brain tissue.…”

Severe Cytokine Release Syndrome and Immune Effector Cell-associated Neurotoxicity Syndrome in a Man Receiving Immune Checkpoint Inhibitors for Lung Cancer

“…He also showed cerebral edematous changes in the brain on MRI, which have been reported in severe ICANS ( 4 , 8 ). In contrast, cerebral edema has not been reported as a typical change in irAE-related encephalitis ( 9 ). Therefore, we considered that the patient had developed ICANS accompanied by CRS.…”

Pembrolizumab-induced encephalitis in a patient with renal cell carcinoma post nephrectomy: A case report

“…In the former case report, corticosteroids were continued and the patient reacted well while pembrolizumab was continued, while in the latter the patient received IVIG therapy for autoimmune encephalitis with continuous pembrolizumab therapy without suspension of tumor treatment. 11 – 13 …”

“…In the former case report, corticosteroids were continued and the patient reacted well while pembrolizumab was continued, while in the latter the patient received IVIG therapy for autoimmune encephalitis with continuous pembrolizumab therapy without suspension of tumor treatment. [11][12][13] The ideal corticosteroid dosage is a topic of discussion. Prednisone or methylprednisolone at a dose of either 2 mg/ kg/day or 1 mg/kg/day should be used to treat irAEs when taking high-dose steroids, according to the general advice.…”