Department of Respiratory Medicine, Kanazawa Medical University, Kahoku, Japan.
Thorac Cancer. 2023 Sep;14(27):2754-2760. doi: 10.1111/1759-7714.15059. Epub 2023 Aug 3.
Immune checkpoint inhibitor (ICI) monotherapy is currently approved for the treatment of advanced non-small cell lung cancer (NSCLC) patients with programmed death ligand-1 (PD-L1) expression ≥50%. However, the efficacy of ICI monotherapy in patients with PD-L1 expression <50% has not yet been fully elucidated. The aim of this study was to identify the clinical characteristics of NSCLC patients with PD-L1 expression <50% who respond to single-agent ICIs and factors that predict response.
Patients with advanced or recurrent NSCLC with a PD-L1 tumor proportion score (TPS) of 50% or less who received new monotherapy with an ICI between July 2012 and December 2022 were retrospectively analyzed. Patients with response were compared with those without response in the post-treatment response assessment.
Among the 37 patients, six (16.2%) NSCLC patients in the response group responded to ICI monotherapy and had a significantly lower body mass index (BMI) (p = 0.003). Significantly more patients in the response group developed immune-related adverse events (irAEs) than in the nonresponse group (p < 0.001). Multivariate analysis identified high BMI as a significant independent risk factor predicting nonresponse to ICI monotherapy in NSCLC patients with PD-L1 < 50%.
Among NSCLC patients with PD-L1 < 50%, those with a higher BMI were more likely to be nonresponders to ICI monotherapy. In addition, the group that responded to ICI monotherapy may have been at higher risk of developing irAEs, suggesting that careful follow-up is warranted.
免疫检查点抑制剂（ICI）单药治疗目前已被批准用于治疗程序性死亡配体-1（PD-L1）表达≥50%的晚期非小细胞肺癌（NSCLC）患者。然而，ICI 单药治疗 PD-L1 表达<50%的患者的疗效尚未完全阐明。本研究旨在确定 PD-L1 表达<50%的 NSCLC 患者对单药 ICI 有反应的临床特征以及预测反应的因素。
回顾性分析了 2012 年 7 月至 2022 年 12 月期间接受新的 ICI 单药治疗的 PD-L1 肿瘤比例评分（TPS）<50%的晚期或复发性 NSCLC 患者。对治疗后反应评估中出现反应和无反应的患者进行比较。
在 37 名患者中，有 6 名（16.2%）对 ICI 单药治疗有反应的 NSCLC 患者的体重指数（BMI）明显较低（p=0.003）。在有反应组中，发生免疫相关不良事件（irAE）的患者明显多于无反应组（p<0.001）。多变量分析确定高 BMI 是 PD-L1<50%的 NSCLC 患者对 ICI 单药治疗无反应的显著独立危险因素。
在 PD-L1<50%的 NSCLC 患者中，BMI 较高的患者对 ICI 单药治疗的反应性较低。此外，对 ICI 单药治疗有反应的患者可能更容易发生 irAE，因此需要谨慎随访。
