摘要标题：中国742例新诊断的晚期呼吸和消化系统肿瘤患者的PD-L1表达分析（基于SP142抗体）

Background: Recent studies have proposed programmed cell death 1 ligand (PD-L1) expression as a distinct biomarker of response to anti-PD-1/PD-L1 therapies. The PD-L1 positive rates in newly diagnosed advanced common solid tumours in China were evaluated. 

研究背景：近期研究提出程序性细胞死亡受体-配体1(PD-L1)表达可作为PD-1/PD-L1抑制剂治疗的一种明确的生物标志物。本研究对我国新诊断的晚期常见实体肿瘤的PD-L1阳性率进行了评估。

Methods: 742 cases of advanced respiratory and digestive system tumour patients were included, including nasopharyngeal carcinoma (33), lung adenocarcinoma (243), lung squamous cell carcinoma (110), small cell lung cancer (20), esophageal cancer (34), gastric cancer (42), duodenal carcinoma (10), colon cancer (78), rectal cancer (31), hepatocellular carcinoma (31), cholangiocarcinoma (67), gallbladder cancer (10), and pancreatic cancer (33). Tumour tissue samples were collected to detect PD-L1 expression by immunohistochemistry (using the SP142 antibody). 

研究方法：本研究纳入了742例晚期新诊断的呼吸和消化系统肿瘤患者，包括：鼻咽癌(33例)，肺腺癌(243例)，肺鳞癌(110例)，小细胞肺癌(20例)，食管癌(34例)，胃癌(42例)，十二指肠癌(10例)，结肠癌(78例)，直肠癌(31例)，肝细胞癌(31例)，胆管癌(67例)，胆囊癌(10例)，胰腺癌(33例)。取肿瘤组织样本，通过免疫组化法(SP142抗体)检测PD-L1表达。

Results: According to PD-L1 strong positive ratio (≥50% in tumour cells (TC), or ≥10 % in immune cells (IC)), in respiratory system tumours, nasopharyngeal carcinoma had the highest strong positive rates of PD-L1, 42% in TC and 21% in IC, followed by lung squamous cell carcinoma (26% in TC and 17% in IC) and lung adenocarcinoma (21% in TC and 12% in IC). Small cell lung cancer did not have PD-L1 strong positive cases. In digestive system tumours, the positive rates of PD-L1 in TC were higher in gallbladder, esophageal and pancreatic cancer, which were 10%, 6% and 6% respectively, followed by colon cancer (3%), gastric cancer (2%) and cholangiocarcinoma (1%). Duodenal carcinoma, rectal cancer and hepatocellular carcinoma did not have PD-L1 strong positive cases in TC. The positive rates of PD-L1 in IC were higher in rectal cancer, hepatocellular carcinoma, gallbladder cancer and cholangiocarcinoma, which were 23%, 23%, 20% and 18% respectively, followed by esophageal cancer (9%), gastric cancer (10%) and colon cancer (10%). Duodenal carcinoma and pancreatic cancer did not have PD-L1 strong positive cases in IC. 

研究结果：SP142抗体的强阳性判读标准是肿瘤细胞(TC)PD-L1阳性比率≥50%，或免疫细胞(IC)PD-L1阳性比率≥10%。结果发现，呼吸系统肿瘤中，鼻咽癌的PD-L1强阳性率最高，TC是42%，IC是21%。其次是肺鳞状细胞癌，TC是26%， IC是17%，肺腺癌中，TC是21%，IC是12%。小细胞肺癌没有PD-L1强阳性病例。消化系统肿瘤中，胆囊癌、食管癌和胰腺癌在TC层面的PD-L1强阳性率分别为10%、6%和6%，其次是结肠癌(3%)、胃癌(2%)和胆管癌(1%)。十二指肠癌、直肠癌及肝细胞癌均未出现TC层面的PD-L1强阳性病例。直肠癌、肝细胞癌、胆囊癌和胆管癌的在IC层面的PD-L1强阳性率分别为23%、23%、20%和18%，其次是食管癌(9%)、胃癌(10%)和结肠癌(10%)。十二指肠癌和胰腺癌在IC层面没有PD-L1强阳性病例。

Conclusions: The PD-L1 strong positive rates of respiratory system tumours were higher than the digestive system tumours. The role of PD-L1 as a predictor of efficacy of PD-1/PD-L1 inhibitors in different types of cancers needs further evaluation. 

研究结论：呼吸系统肿瘤的PD-L1强阳性率高于消化系统肿瘤。PD-L1在不同类型肿瘤中作为PD-1/PD-L1抑制剂的疗效预测因子的作用需要进一步的评估。