免疫检查点抑制剂（ICIs）可改善肺癌预后；然而，ICI 相关的间质性肺疾病 (ILD) 是致命的且难以预测。在此，我们假设放射成像中预先存在的肺部炎症可能是 ILD 发病的潜在危险因素。因此，我们研究了肺癌中 18F-FDG-PET/CT 的非癌性肺 (NCL) 高摄取与 ICI-ILD 之间的关联。 ICI 治疗前三个月内接受 FDG-PET/CT 的原发性肺癌患者被追溯纳入。利用人工智能从原发肿瘤对侧肺中提取 NCL 区域（背景肺）。 NCL 对 FDG 的摄取通过 SUVmax (NCL-SUVmax)、SUVmean (NCL-SUVmean) 和总糖酵解活性 (NCL-TGA) 进行评估，定义为 NCL-SUVmean×NCL 体积 [mL]。 NCL-SUVmean 和 NCL-TGA 使用以下四个 SUV 阈值计算：0.5、1.0、1.5 和 2.0。 在 165 名患者中，28 名 (17.0%) 发展为 ILD。单变量分析显示，NCL-SUVmax、NCL-SUVmean2.0（SUV 阈值=2.0）和 NCL-TGA1.0（SUV 阈值=1.0）的高值与 ILD 发病显着相关（所有 p = 0.003）。根据年龄、肿瘤 FDG 摄取和预先存在的间质性肺异常进行调整的多变量分析显示，高 NCL-TGA1.0 (≥149.45) 与 ILD 发病独立相关（比值比，6.588；p = 0.002）。高 NCL-TGA1.0 组的 ILD 两年累积发生率显着高于低组（58.4% vs. 14.4%；p < 0.001）。FDG-PET/CT 上 NCL 的高摄取与ICI-ILD 开发，可作为原发性肺癌 ICI 治疗前的风险分层工具。版权所有 © 2024 大学放射科医生协会。由爱思唯尔公司出版。保留所有权利。

Immune checkpoint inhibitors (ICIs) have improved lung cancer prognosis; however, ICI-related interstitial lung disease (ILD) is fatal and difficult to predict. Herein, we hypothesized that pre-existing lung inflammation on radiological imaging can be a potential risk factor for ILD onset. Therefore, we investigated the association between high uptake in noncancerous lung (NCL) on 18F- FDG-PET/CT and ICI-ILD in lung cancer.Patients with primary lung cancer who underwent FDG-PET/CT within three months prior to ICI therapy were retrospectively included. Artificial intelligence was utilized for extracting the NCL regions (background lung) from the lung contralateral to the primary tumor. FDG uptake by the NCL was assessed via the SUVmax (NCL-SUVmax), SUVmean (NCL-SUVmean), and total glycolytic activity (NCL-TGA)defined as NCL-SUVmean×NCL volume [mL]. NCL-SUVmean and NCL-TGA were calculated using the following four SUV thresholds: 0.5, 1.0, 1.5, and 2.0.Of the 165 patients, 28 (17.0%) developed ILD. Univariate analysis showed that high values of NCL-SUVmax, NCL-SUVmean2.0 (SUV threshold=2.0), and NCL-TGA1.0 (SUV threshold=1.0) were significantly associated with ILD onset (all p = 0.003). Multivariate analysis adjusted for age, tumor FDG uptake, and pre-existing interstitial lung abnormalities revealed that a high NCL-TGA1.0 (≥149.45) was independently associated with ILD onset (odds ratio, 6.588; p = 0.002). Two-year cumulative incidence of ILD was significantly higher in the high NCL-TGA1.0 group than in the low group (58.4% vs. 14.4%; p < 0.001).High uptake of NCL on FDG-PET/CT is correlated with ICI-ILD development, which could serve as a risk stratification tool before ICI therapy in primary lung cancer.Copyright © 2024 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.