PD-L1的表达和肿瘤退缩率对鼻咽癌预后的影响

目的： 探讨鼻咽癌患者肿瘤组织中程序性死亡配体-1(programmed death ligand-1，PD-L1)的表达情况、 放射治疗和化学治疗(以下简称放化疗)后的肿瘤体积退缩率以及两者对预后的影响。方法： 采用免疫组织化学方法 检测2014 年1 月至2016 年6 月于中南大学湘雅二医院诊治的86 例初治非转移性鼻咽癌患者肿瘤组织中PD-L1 的表达 水平；同时收集患者的相关临床资料、放化疗前及放射治疗后1 个月的肿瘤退缩率；进一步分析PD-L1 的表达、肿瘤 体积退缩率与其疗效及临床预后的关系。结果： 纳入研究的86 例鼻咽癌患者肿瘤组织中，PD-L1 的阳性高表达患者 为30 例(34.88%)，PD-L1 阳性低表达患者为56 例(65.12%)。PD-L1 在鼻咽癌患者肿瘤组织中的表达强度与性别、年 龄、吸烟史、同步放化疗、病理分型、N分期、肿瘤分期及治疗前外周血EB病毒DNA载量均无关(均P>0.05)；但与 肿瘤退缩率和肿瘤T分期有关(均P<0.05)。组织中PD-L1 的表达水平是肿瘤退缩率的危险因素(OR=0.226，P<0.05)。 与PD-L1 阳性低表达患者相比，PD-L1 阳性高表达患者无疾病进展生存期明显缩短(P<0.05)；且高肿瘤退缩率患者较 低退缩率患者无疾病进展生存期延长(P<0.05)。结论： 鼻咽癌患者肿瘤组织中的PD-L1 高表达、放化疗前后低肿瘤退 缩率预示着有较差的预后。

Effect of PD-L1 and tumor regression rate on prognosis of nasopharyngeal carcinoma

Objective: To explore the expression level of programmed death ligand-1 (PD-L1) and the tumor regression rate after chemoradiotherapy, and to investigate their influence on the prognosis of patients with nasopharyngeal carcinoma. Methods: Eighty-six patients, who were initially diagnosed with non-metastatic nasopharyngeal carcinoma in the Second Xiangya Hospital of Central South University from January 2014 to June 2014, were recruited. Positive expression of PD-L1 in prepared sections of nasopharyngeal carcinoma tissues was detected by immunohistochemical staining. The clinical data of recruited patients and the tumor regression rate were calculated beforechemoradiotherapy and 1 month after chemoradiotherapy. In addition, the potential influence of PD-L1 level and the tumor regression rate after chemoradiotherapy on therapeutic efficacy and the prognosis of nasopharyngeal carcinoma were assessed. Results: Among the 86 patients with nasopharyngeal carcinoma, there were 30 patients with high expression of PD-L1 in nasopharyngeal carcinoma sections (34.88%), while there were 56 patients with low expression (65.12%). Expression levels of PD-L1 in nasopharyngeal carcinoma tissues were not related with sex, age, smoking history, concurrent chemoradiotherapy, pathological type, N staging, tumor staging, and pretreatment EBV-DNA load in peripheral blood in the affected patients (all P>0.05). But the expression level of PD-L1 was related to the tumor regression rate and T staging in the patients with nasopharyngeal carcinoma (both P<0.05). The expression levels of PD-L1 in nasopharyngeal carcinoma tissues was a risk factor for tumor regression rate (OR=0.226, P<0.05). Compared with the patients with low expression levels of PD-L1, there was shorter disease-free survival in the patients with high expression levels of PD-L1 (P<0.05). Moreover, compared with the patients with low tumor regression rate, the nasopharyngeal carcinoma patients with high tumor regression rate showed a favorable disease-free survival (P<0.05). Conclusion: A high expression level of PD-L1 and a low tumor regression rate after chemoradiotherapy are unfavorable to the prognosis of nasopharyngeal carcinoma.