Although rare, several immune-related adverse effects can be life-threatening. Here, we describe a metastatic gastric cancer patient presenting with nivolumab-related myasthenia gravis and myocarditis, a previously unreported adverse effect of gastric cancer treatment. A 66-year-old man with metastatic gastric cancer visited the emergency department because of dizziness after the first dose of nivolumab. Diagnoses of nivolumab-related myasthenia gravis and myocarditis were established. Myocardial biopsy results and anti-acetylcholine receptor antibody positivity confirmed the diagnoses. Despite plasma exchange and intravenous methylprednisolone and immunoglobulin administration, the patient’s general condition gradually worsened, and he died. Strict monitoring for cardiac and neuromuscular symptoms after nivolumab administration is necessary to rapidly treat these adverse effects.

中文翻译：

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一例转移性胃癌患者发生纳武单抗相关重症肌无力和心肌炎的罕见病例

虽然罕见，但一些与免疫相关的不良反应可能危及生命。在这里，我们描述了一名转移性胃癌患者，该患者表现出与纳武单抗相关的重症肌无力和心肌炎，这是以前未报告的胃癌治疗不良反应。一名患有转移性胃癌的 66 岁男性因第一剂纳武单抗后头晕而到急诊室就诊。确立了纳武单抗相关重症肌无力和心肌炎的诊断。心肌活检结果和抗乙酰胆碱受体抗体阳性证实了诊断。尽管进行了血浆置换、静脉注射甲泼尼龙和免疫球蛋白，但患者的全身情况逐渐恶化，最终死亡。