目的：检测食管鳞癌患者外周血中程序性死亡分子1 （programmed cell death 1,PD-1）、程序性死亡分子1配体（pro-grammed cell death ligand 1,PD-L1）及IFN-γ表达情况，并分析其临床意义。 方法 选取2016年6月至2017年4月河北医科大学第四医院胸外科90例食管鳞状细胞癌患者（其中50例患者行手术治疗）和40例健康对照者为研究对象，收集研究其外周血液标本，采用酶联免疫吸附方法检测血清中可溶性PD-1 （sPD-1）、可溶性PD-L1 （sPD-L1）及IFN-γ的表达水平。采用SPSS 24.0软件对数据进行检验和相关性分析。 结果： 食管鳞癌组血清中sPD-1、sPD-L1及IFN-γ水平均明显高于正常对照组（ P <0.05）；食管鳞癌组手术前血清sPD-L1、IFN-γ水平均明显高于术后（ P <0.05）,而sPD-1水平两组比较无明显差异（ P >0.05）。sPD-1、sPD-L1的表达水平与临床病理特征无明显相关（ P >0.05），IFN-γ的表达水平与淋巴结转移情况相关（ P <0.05），与T分期、TNM分期、肿瘤体积大小、肿瘤部位、组织分化程度、性别、年龄无明显相关（ P >0.05）。血清中sPD-L1表达水平与IFN-γ无明显相关（ P >0.05）。 结论：食管鳞癌患者血清中sPD-L1较正常人表达升高，且术后表达较术前减少，说明血清中sPD-L1表达水平与病情发展变化有一定相关性。

Objective：To evaluate the expressionlevelsofprogrammeddeath-1 (PD-1), programmeddeathligand-1 (PD-L1) and IFN-γ in the peripheral blood of patients with esophageal squamous cell carcinoma (ESCC), and to ex-plore their clinical implications. Methods：A total of 90 ESCC patients (including 50 patients that underwent surgi-cal treatment) and 40 healthy controls were enrolled in the study. The periphery blood samples of the participants were collected and the expression levels of soluble PD-1 (sPD-1), soluble PD-L1 (sPD-L1) and IFN-γ in the serum were tested by enzyme-link immunology method. The data were tested and analyzed with SPSS 24.0 software. Re-sults：The expression levels of sPD-1,sPD-L1 and IFN-γ in the blood of ESCC group were significantly higher than those in the healthy controls (P<0.05); the preoperative level of sPD-L1 and IFN-γ in ESCC patients was significant-ly higher than that of postoperative level (P<0.05), whereas no significant difference was observed in the expression levels of sPD-1 before and after the surgery (P>0.05). sPD-1 and sPD-L1 expression had no remarkable correlation with clinicopathological manifestations (P>0.05); however, IFN-γ expression was related to lymph node metastasis (P<0.05), but not with other manifestations (T stage, TNM stage, tumor size, tumor location, tumor cell differentia-tion, sex, and age) (P>0.05). The expression level of sPD-L1 had no significant correlation with IFN-γ (P>0.05).Conclusion：The serum level of sPD-L1 was higher in ESCC patients than that in healthy controls, and the post-op-erative sPD-L1 level was decreased compared with pre-operative level, indicating sPD-L1 may be associated with ESCC development.