Division of Medical Oncology-Hematology, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University College of Medicine, Seoul, Korea.
Division of Rheumatology, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University College of Medicine, Seoul, Korea.
J Chemother. 2023 May;35(3):275-280. doi: 10.1080/1120009X.2022.2073162. Epub 2022 May 13.
Pembrolizumab is an immune checkpoint inhibitor (ICI) against the programmed death-1 receptor. Herein, we introduce a rare adverse effect during using pembrolizumab. We present the case of an 80-year-old man with biopsy-proven unresectable double primary squamous cell carcinoma and large cell neuroendocrine carcinoma of the lung. After using pembrolizumab for 10 months, he complained of muscle weakness of both upper and lower extremities. In a nerve conduction study, the repetitive nerve stimulation test in the abductor digiti minimi was diagnostic of Lambert-Eaton myasthenic syndrome (LEMS): low in the amplitude of compound muscle action potential (1.4 mV), 28.6% decrement in the 5-Hz stimulation, and 579% increment in the 50-Hz stimulation. The disease did not progress after the discontinuation of pembrolizumab, even without any anti-cancer treatment for 12 months. We believe our clinical experience of this rare and unexpected adverse effect should be shared.
帕博利珠单抗是一种针对程序性死亡受体 1 的免疫检查点抑制剂（ICI）。本文介绍了使用帕博利珠单抗时出现的一种罕见不良反应。我们报告了一例 80 岁男性，经活检证实患有不可切除的双原发性肺鳞状细胞癌和大细胞神经内分泌癌。使用帕博利珠单抗 10 个月后，他主诉出现上下肢肌肉无力。神经传导研究中，小指展肌重复神经刺激试验提示符合 Lambert-Eaton 肌无力综合征（LEMS）：复合肌肉动作电位振幅降低（1.4 mV），5 Hz 刺激时递减 28.6%，50 Hz 刺激时递增 579%。停用帕博利珠单抗后，疾病未进展，即使在 12 个月内未进行任何抗癌治疗也是如此。我们认为，应该分享我们对这种罕见且意外不良反应的临床经验。
