Xu Haipeng, Chen Xueyan, Lin Dong, Zhang Jing, Li Chao, Zhang Dianbao, Zhang Xianfen
Department of Thoracic Oncology, Fujian Cancer Hospital, Fujian Medical University Cancer Hospital, Fuzhou 350014, People's Republic of China.
Department of Pathology, Fujian Cancer Hospital, Fujian Medical University Cancer Hospital, Fuzhou 350014, People's Republic of China.
Onco Targets Ther. 2019 Dec 30;12:11541-11547. doi: 10.2147/OTT.S223643. eCollection 2019.
Programmed death-ligand 1 (PD-L1) expression as measured by immunohistochemistry (IHC) has been employed to predict the efficacy of anti-PD-1/PD-L1 therapy. Nevertheless, heterogeneous PD-L1 expression represents a challenge for the selection of patients for anti-PD-1/PD-L1 therapy.
PD-L1 expression using clone 22C3 in 76 resected non-small-cell lung cancer and paired nodal metastases was assessed and classified according to the proportion of immunostained tumour cells using cutoff values of 1%, 5%, and 50%.
The concordance rates for PD-L1 expression between primary and metastatic lymph nodes (N1) at these cutoff values were 67.7% (21/31) (Kappa value: 0.455, p<0.000), 60.0% (15/25) (Kappa value: 0.668, p<0.000), and 62.5% (5/8) (Kappa value: 0.497, p<0.000). In 36 paired N1 lymph nodes and N2 lymph nodes, 54.5% (6/11) (Kappa value: 0.625, p<0.000) of cases of PD-L1 expression were coincident at cutoffs of 1%. If stratified by adenocarcinoma and squamous cell carcinoma, 87.5% (14/16) (Kappa value: 0.830, p<0.000) of cases at the 1% cutoff and 46.7% (7/15) (Kappa value: 0.324, p<0.000) of cases at the 1% cutoff were coincident.
The results of this study demonstrate that the concordance of PD-L1 expression between primary tumour and nodal metastases is low in non-small-cell lung cancer but is high in adenocarcinoma. Our results also suggest that PD-L1 expression in either lymph nodes or tumour tissues does not predict survival. PD-L1 detection in metastatic lymph nodes is not a suitable replacement for PD-L1 detection in the primary lesion.
通过免疫组织化学（IHC）测定的程序性死亡配体1（PD-L1）表达已被用于预测抗PD-1/PD-L1治疗的疗效。然而，PD-L1表达的异质性给抗PD-1/PD-L1治疗患者的选择带来了挑战。
使用克隆号22C3评估76例切除的非小细胞肺癌及其配对的淋巴结转移灶中的PD-L1表达，并根据免疫染色肿瘤细胞的比例，以1%、5%和50%的临界值进行分类。
在这些临界值下，原发灶与转移淋巴结（N1）之间PD-L1表达的一致性率分别为67.7%（21/31）（Kappa值：0.455，p<0.000）、60.0%（15/25）（Kappa值：0.668，p<0.000）和62.5%（5/8）（Kappa值：0.497，p<0.000）。在36对N1淋巴结和N2淋巴结中，在1%的临界值下，54.5%（6/11）（Kappa值：0.625，p<0.000）的病例PD-L1表达一致。若按腺癌和鳞状细胞癌分层，在1%的临界值下，87.5%（14/16）（Kappa值：0.830，p<0.000）的病例和46.7%（7/15）（Kappa值：0.324，p<0.000）的病例表达一致。
本研究结果表明，非小细胞肺癌中原发肿瘤与淋巴结转移灶之间PD-L1表达的一致性较低，但在腺癌中较高。我们的结果还表明，淋巴结或肿瘤组织中的PD-L1表达不能预测生存率。转移淋巴结中的PD-L1检测不适用于替代原发灶中的PD-L1检测。
