Successful Early Treatment of Anti‐N‐Methyl‐ <scp>d</scp> ‐Aspartate Receptor Encephalitis Associated With Small Cell Lung Cancer in an Elderly Male Patient: A Case Report

This was a rare case of anti-NMDAR encephalitis associated with SCLC in an elderly male patient. Diagnosis in elderly individuals is often challenging because of the atypical presentations and lower tumor association. Nevertheless, timely intervention initiation may lead to favorable outcomes. Clinicians should consider autoimmune encephalitis, including anti-NMDAR encephalitis, when evaluating acute onset neuropsychiatric symptoms in elderly individuals and initiate early immunotherapy alongside tumor screening.