Limbic encephalitis associated with anti-Hu antibody induced by atezolizumab treatment for small cell lung cancer: A case report.

With the emergence and frequent use of immune checkpoint inhibitors (ICIs), reports of immunotherapy-induced limbic encephalitis have begun to appear. The present study describes the case of a patient with small cell lung cancer who developed Hu-associated limbic encephalitis while being treated with atezolizumab. After treatment with high-dose steroids and intravenous immunoglobulin, the neurological symptoms of the patient (including confusion, short-term memory loss, disorientation, and impaired calculation ability) remained stable for 3 months, after which the patient was lost to follow-up. ICIs may accelerate autoimmune reactions that target paraneoplastic origin autoantigens. Clinicians should be alert to the risk of ICI-induced paraneoplastic neurological syndromes in patients with tumors, such as small cell lung cancer, that are traditionally associated with paraneoplastic neurological syndromes.