Recently, immune checkpoint inhibitors (ICIs) have become the standard treatment option for patients with lung cancer, including small cell lung cancer (SCLC). ICI-induced neurological immune-related adverse events are rare and exhibit diverse clinical manifestations, often leading to missed or delayed diagnosis. Herein, we report the case of a patient with extensive-stage SCLC who received atezolizumab with etoposide/platinum and gradually developed neurological symptoms after three cycles of chemoimmunotherapy. Subsequently, the patient received a diagnosis of subacute immune-related cerebellar ataxia and was treated successfully with pulse steroid therapy. The patient exhibited almost complete remission of neurological symptoms and had progression-free survival for >24 months.

中文翻译：

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Atezolizumab 在患有广泛期小细胞肺癌的患者中诱导亚急性小脑共济失调。

近年来，免疫检查点抑制剂（ICIs）已成为肺癌患者的标准治疗选择，包括小细胞肺癌（SCLC）。ICI 引起的神经免疫相关不良事件很少见，且临床表现多样，常常导致漏诊或延迟诊断。在此，我们报告一例广泛期 SCLC 患者接受阿特珠单抗联合依托泊苷/铂治疗，并在三个周期的化学免疫治疗后逐渐出现神经系统症状。随后，患者被诊断为亚急性免疫相关小脑共济失调，并通过脉冲类固醇疗法成功治疗。该患者的神经系统症状几乎完全缓解，并且无进展生存期超过 24 个月。