Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea.
Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea.
Pathology. 2024 Dec;56(7):969-981. doi: 10.1016/j.pathol.2024.06.006. Epub 2024 Aug 22.
Programmed cell death-ligand 1 (PD-L1) expression is a predictive biomarker for response to immune checkpoint inhibitor in head and neck squamous cell carcinoma. Given the range of antibodies and platforms for PD-L1 testing, it is essential to understand the performance of different staining and scoring methods. PD-L1 expression in 156 head and neck mucosal squamous cell carcinoma (HNmSCC) cases at Asan Medical Center was assessed using 106 tissue microarray (TMA) cores and 50 whole slides. Three standardised PD-L1 assays (22C3 pharmDx, SP263, and 28-8 pharmDx) and one laboratory-developed test (22C3 LDT) were evaluated: the combined positive score (CPS) with ≥1, ≥20, and ≥50 cut-offs, and the tumour positive score (TPS) with ≥1%, ≥20%, ≥50% cut-offs. Concordance on a continuous scale among the assays was good to excellent for CPS [intraclass correlation coefficient (ICC) range 0.73-0.94] and TPS (ICC range 0.70-0.94) and in both TMA and whole slides cohorts. Stratification by variable cut-offs demonstrated moderate to good agreement among most assays, as analysed by Gwet's AC1. PD-L1 expression was significantly correlated with tumour location using the 22C3 pharmDx assay (CPS, p=0.014; TPS, p=0.033). Notable concordance was found among PD-L1 assays, suggesting their potential interchangeability in HNmSCC.
程序性细胞死亡配体 1（PD-L1）表达是头颈部鳞状细胞癌对免疫检查点抑制剂反应的预测性生物标志物。鉴于 PD-L1 检测的抗体和平台种类繁多，了解不同染色和评分方法的性能至关重要。使用 106 个组织微阵列（TMA）核心和 50 个全切片评估了在 Asan 医疗中心的 156 例头颈部黏膜鳞状细胞癌（HNmSCC）病例中的 PD-L1 表达。评估了三种标准化 PD-L1 检测方法（22C3 pharmDx、SP263 和 28-8 pharmDx）和一种实验室开发的检测方法（22C3 LDT）：以≥1、≥20 和≥50 为截断值的联合阳性评分（CPS）和以≥1%、≥20%、≥50%为截断值的肿瘤阳性评分（TPS）。CPS（组内相关系数（ICC）范围 0.73-0.94）和 TPS（ICC 范围 0.70-0.94）在 TMA 和全切片队列中，各检测方法之间在连续尺度上的一致性均良好到极好。根据可变截断值进行分层分析显示，大多数检测方法之间具有中度到良好的一致性，Gwet's AC1 分析结果如此。使用 22C3 pharmDx 检测方法，PD-L1 表达与肿瘤位置显著相关（CPS，p=0.014；TPS，p=0.033）。PD-L1 检测方法之间存在显著的一致性，这表明它们在 HNmSCC 中具有潜在的可互换性。
