程序性细胞死亡配体 1 (PD L1) 是一种在肿瘤细胞中高度表达的跨膜蛋白。免疫检查点抑制剂治疗以 PD-1/PD-L1 阻断诱导肿瘤消退为目标。 PD-L1 表达的免疫组织化学 (IHC) 使患者能够选择免疫治疗，并可被视为头颈鳞状细胞癌 (HNSCC) 免疫治疗的潜在预测生物标志物。确定 HNSCC 中的 PDL1 表达，与临床病理特征和相关性相关联。我们回顾性分析了 2017 年 1 月至 2018 年 11 月期间在我们三级医院收治的 59 例 HNSCC 病例，并随访至死亡/2022 年 11 月的总生存期。使用联合阳性评分 (CPS) 与抗体克隆 22C3 对 59 例患者进行 PD-L1 的 IHC 分析进行了 HNSCC 病例。 PD-L1表达与临床病理特征和转归相关。SPSS20.0采用Pearson卡方检验分析PD-L1表达与临床病理参数的相关性。采用Kaplan-Meier法计算生存曲线，并采用log-rank检验分析差异。共有25例（42.4%）PDL表达阳性（CPS≥1）。 16/25例（27.1%）属于CPS（≥1，<10）。两位病理学家注意到 PD-L1 IHC 表达几乎完美的观察者间一致性。 PD-L1评分与临床病理特征之间没有统计学上显着的相关性。PD-L1状态的检测可以进一步了解印度HNSCC患者PD-L1表达的频率，从而可能改善临床治疗策略，确保我们的患者获得最大的治疗免疫疗法的好处。版权所有：© 2024 口腔颌面病理学杂志。

Programmed cell death ligand 1 (PD L1) is a transmembrane protein that is highly expressed in neoplastic cells. Therapy with immune checkpoint inhibitors target PD-1/PD-L1 blockade-inducing tumour regression. Immunohistochemistry (IHC) for PD-L1 expression enables patient selection for immunotherapy and can be considered as a potential predictive biomarker for immunotherapy in head and neck squamous cell carcinoma (HNSCC).To determine the PDL1 expression in HNSCC, to correlate with clinicopathological features and outcome.We retrospectively analysed 59 cases of HNSCC at our Tertiary Hospital between January 2017 and November 2018 and followed up until death/Nov 2022 for Overall survival.IHC analysis of PD-L1 using Combined Positive Score (CPS) with antibody clone 22C3 in 59 cases of HNSCC was performed. PD-L1 expression was correlated with clinicopathological features and outcomes.Pearson Chi-square test was used to analyse the correlation between PD-L1 expression and clinicopathological parameters using SPSS20.0. Survival curves were calculated by Kaplan-Meier method, and differences were analysed by log-rank test.A total of 25 cases (42.4%) had positive PDL expression (CPS ≥1). 16/25 cases (27.1%) belonged to CPS (≥1, <10). An almost-perfect interobserver agreement was noted by two pathologists for PD-L1 IHC expression. No statistically significant correlation was noted between PD-L1 score and clinicopathologic features.Detection of PD-L1 status gives further insight into frequency of PD-L1 expression in Indian HNSCC patients to possibly improve clinical treatment strategies, ensuring that our patients get the maximum therapeutic benefit of immunotherapy.Copyright: © 2024 Journal of Oral and Maxillofacial Pathology.