胃肠胰神经内分泌肿瘤微卫星状态与PD-L1表达的相关性及临床意义

Correlation Between Microsatellite Status and PD-L1 Expression in Gastrointestinal Pancreatic Neuroendocrine Tumors and Its Clinical Significance

目的分析胃肠胰神经内分泌肿瘤(GEP-NENs)的微卫星状态及其与PD-L1表达的相关性和临床意义。方法收集47例经病理检查诊断为GEP-NEN患者的组织样本,应用免疫组织化学法检测组织样本中MMR蛋白(MLH1、MSH2、MSH6、PMS2)和PD-L1的表达。分析GEP-NENs的微卫星状态与PD-L1表达的相关性。结果GEP-NENs的微卫星状态与其组织学分级、肿瘤大小、临床分期、淋巴结转移、肿瘤部位、年龄及性别无关(P>0.05)。GEP-NENs组织中PD-L1表达与临床分期相关(P<0.05)。在微卫星不稳定的GEP-NENs中PD-L1阳性表达率为88.9%,高于微卫星稳定的GEP-NENs(11.1%),差异具有显著统计学意义(P<0.05)。结论胃肠胰神经内分泌肿瘤微卫星不稳定可以作为免疫检查点抑制剂PD-L1的阳性预测标志物。

Objective To explore the correlation between microsatellite status and PD-L1 expression in gastrointestinal pancreatic neuroendocrine tumors(GEP-NENs)and its clinical significance.Methods Tissue samples from 47 patients with established pathological diagnosis of GEP-NENs were collected,and the expression of MMR protein(MLH1,MSH2,MSH6,PMS2)and PD-L1 in the tissues were detected by immunohistochemistry.To analyze the correlation between microsatellite status and PD-L1 expression in GEP-NENs.Results The microsatellite status of GEP-NENs was not related to histological grade,tumor size,clinical stage,lymph node metastasis,tumor site,age and sex(P>0.05).The expression of PD-L1 in GEP-NENs tissues was related to clinical stage(P<0.05).The positive expression rate of PD-L1 in GEP-NENs with microsatellite instability was 88.9%,which was higher than that in GEP-NENs with microsatellite stability 11.1%,it has statistically significant(P<0.05).Conclusion Microsatellite instability of gastrointestinal pancreatic neuroendocrine tumors could be a positive predictive marker of immune checkpoint inhibitor PD-L1.