Yamazoe Masami, Hatakeyama Taku, Furukawa Kento, Kato Koji, Horiuchi Kazuhiro
Pulmonology, Hakodate Municipal Hospital, Hakodate, JPN.
Pulmonology, Sapporo Medical University School of Medicine, Sapporo, JPN.
Cureus. 2023 Jan 9;15(1):e33557. doi: 10.7759/cureus.33557. eCollection 2023 Jan.
The case of a 70-year-old man who developed Lambert-Eaton myasthenic syndrome (LEMS) while receiving treatment for extensive-stage small-cell lung cancer (SCLC) is presented. He started receiving maintenance immunotherapy with atezolizumab following four cycles of combination therapy with , carboplatin, and etoposide. After five cycles of maintenance therapy, he complained of muscle weakness in the lower limbs and fatigue. Electromyographic findings and positive results for anti-P/Q-type voltage-gated calcium channel antibody made a diagnosis of LEMS. Based on the onset time of LEMS and the state of his underlying cancer at the time of the appearance of neurological symptoms, he was diagnosed with LEMS as an immune-related adverse event (irAE) induced by atezolizumab. After discontinuing atezolizumab treatment and initiating combination therapy with steroid pulse plus intravenous immunoglobulin, his neurological symptoms improved. Although 18 months have passed since the discontinuation of atezolizumab treatment, there has been neither recurrence of neurological symptoms nor a progression of his cancer without salvage chemotherapy. This is a rare case of LEMS as a neurological irAE induced by atezolizumab. Clinicians must be aware of the potential for LEMS to develop in SCLC patients taking atezolizumab treatment.
本文介绍了一例70岁男性患者，该患者在接受广泛期小细胞肺癌（SCLC）治疗时出现了兰伯特-伊顿肌无力综合征（LEMS）。他在接受了四个周期的顺铂、卡铂和依托泊苷联合治疗后，开始接受阿替利珠单抗维持免疫治疗。在五个周期的维持治疗后，他出现了下肢肌肉无力和疲劳的症状。肌电图检查结果以及抗P/Q型电压门控钙通道抗体检测呈阳性，确诊为LEMS。根据LEMS的发病时间以及出现神经症状时其基础癌症的状态，他被诊断为阿替利珠单抗诱导的免疫相关不良事件（irAE）导致的LEMS。在停用阿替利珠单抗治疗并开始使用类固醇冲击联合静脉注射免疫球蛋白进行联合治疗后，他的神经症状有所改善。尽管自停用阿替利珠单抗治疗以来已经过去了18个月，但在未进行挽救性化疗的情况下，他既没有神经症状复发，癌症也没有进展。这是一例由阿替利珠单抗引起的LEMS作为神经irAE的罕见病例。临床医生必须意识到接受阿替利珠单抗治疗的SCLC患者发生LEMS的可能性。
