ニボルマブ投与後に重症筋無力症を発症した１例

A ７０s female suffering from recurrent gastric cancer presented with ptosis, dysphagia and lower limb and neck muscles weakness with elevation of serum CK levels after second treatment with the immune checkpoint inhibitor nivolumab. The symptoms suggested myasthenia gravis （MG）, although anti-acetylcholine receptor antibody and muscle-specific receptor tyrosine kinase antibody were negative. Steroid treatment quickly normalized CK levels and relieved MG symptoms. Nivolumab-induced MG can rapidly become severe and potentially fatal, and a prompt and accurate response is desirable.