PD-L1高表達型肺癌的治療方法

程序性細胞死亡蛋白1 (Programmed cell death protein 1, PD-1)是免疫細胞上的免疫檢查點蛋白，能抑制免疫系統攻擊身體內其他細胞。⁸⁹ 癌當免疫細胞上的 PD-1 與腫瘤細胞上的程序性細胞死亡配體 1 (Programmed cell death ligand 1, PD-L1) 結合便會抑制免疫系統攻擊腫瘤細胞。⁸⁹

PD-1 和 PD-L1 免疫檢查點抑制劑能阻截腫瘤細胞上的PD-L1與免疫細胞上的PD-1之間的結合，從而激活免疫系統對抗腫瘤細胞。⁸⁹ PD-1 或 PD-L1 抑制劑通常作為晚期非小細胞肺癌（NSCLC）的臨床治療方案。³⁷

NSCLC 治療前應先評估晚期 NSCLC 患者的腫瘤是否存在驅動基因突變，以及是否表達 PD-L1，然後根據這些信息來考慮初始治療方案⁹⁰。PD-L1 表達水平高於50%的肺癌會被稱為 PD-L1 高表達型肺癌。³⁷

副作用
儘管免疫檢查點抑制劑有顯著的臨床療效，但同時亦會為病人帶來一些被稱為免疫相關不良事件 (immune-related adverse event, irAE) 的獨特副作用，其中包括皮膚（如皮疹）、胃腸（如腹瀉、結腸炎）、肝臟（如肝病）、內分泌等炎性反應。⁹¹

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