Krebs von den Lungen-6（KL-6）作为一种肿瘤标志物，也被用作间质性肺炎（IP）的诊断工具。然而，KL-6在非小细胞肺癌（NSCLC）的免疫检查点抑制剂（ICI）治疗中的意义，特别是对于没有IP的患者，尚不清楚。本多中心、回顾性研究纳入了接受ICI治疗的晚期NSCLC患者，分析了血清KL-6值与ICI疗效的关联，以及血清KL-6值与ICI诱导的间质性肺疾病（ILD）发生的关联，重点关注没有IP的患者。共有322名患者在ICI治疗前提供了可用的KL-6值。在202名没有IP的接受ICI单药治疗的患者中，高KL-6组（≥500 U/mL）的无进展生存期（PFS）和总生存期（OS）显著较低（中位数：2.1个月 vs. 3.6个月，p = 0.048；中位数：9.2个月 vs. 14.5个月，p = 0.035）。KL-6高组与KL-6低组的响应率之间无显著差异（19% vs. 29%，p = 0.14）。多变量分析中，高KL-6是ICI单药治疗的不良PFS（风险比[HR]，1.52；95%可信区间[CI]，1.10-2.11，p = 0.012）和OS（HR，1.51；95% CI，1.07 - 2.13，p = 0.019）的显著预测因子。在IP有无的患者中，高KL-6组与低KL-6组之间ILD的发生率没有显著差异（20% vs. 15%，p = 1.00；12% vs. 12%，p = 1.00）。在没有IP的NSCLC的ICI单药治疗中，血清KL-6水平升高与不良预后相关。©2023该作者对Springer-Verlag GmbH Germany, Springer Nature的独家许可授权。

Krebs von den Lungen-6 (KL-6) functions as a tumor marker, as well as a diagnostic tool for interstitial pneumonia (IP). However, the significance of KL-6 in the immune-checkpoint inhibitor (ICI) treatment of non-small cell lung cancer (NSCLC), especially in patients without IP, is unknown.This multicenter, retrospective study, which included patients with advanced NSCLC who received ICI therapy, analyzed the association between serum KL-6 values and ICI efficacy and the association between serum KL-6 values and ICI-induced interstitial lung disease (ILD) occurrence, focusing primarily on patients without IP.In total, 322 patients had available KL-6 values before ICI therapy. Among 202 patients without IP who received ICI monotherapy, the high-KL-6 group (≥ 500 U/mL) showed significantly shorter progression-free survival (PFS) and overall survival (OS) than the low-KL-6 group (< 500 U/mL) (median: 2.1 vs. 3.6 months, p = 0.048; median: 9.2 vs. 14.5 months, p = 0.035). There was no significant difference in response rate between the KL-6 high and low groups (19% vs. 29%, p = 0.14). In the multivariate analysis, high KL-6 was a significant predictor of poor PFS (hazard ratio [HR], 1.52; 95% confidence interval [CI] 1.10-2.11, p = 0.012) and OS (HR, 1.51; 95% CI 1.07 - 2.13, p = 0.019) for patients treated with ICI monotherapy. There was no significant difference in the occurrence rate of ILD between the high KL-6 and low KL-6 groups in patients with (20% vs. 15%, p = 1.00) or without IP (12% vs. 12%, p = 1.00).In ICI monotherapy for NSCLC without IP, elevated serum KL-6 levels were associated with poorer outcomes.© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.