Autoimmune encephalitis following treatment with durvalumab for small-cell lung cancer.

The traditional treatment for small-cell lung cancer (SCLC) has been traditional systemic platinum-containing chemotherapy because the response rate is 50-90%. Durvalumab is an immune checkpoint inhibitor that blocks the binding of programmed cell death protein 1 and programmed cell death 1 ligand 1. Durvalumab combined with traditional chemotherapy agents has been recommended as the first-line treatment for extensive-stage SCLC, but its use may cause immune-related adverse events. Autoimmune encephalitis is a rare and potentially fatal neurological adverse event. This current case report describes a male patient in his late 50s with ES-SCLC who developed autoimmune encephalitis associated with durvalumab treatment after three cycles of combination chemotherapy. This current case furthers the understanding of autoimmune encephalitis caused by durvalumab treatment.