Farkašová Anna, Tancoš Vladimír, Kviatkovská Zuzana, Huťka Zdenko, Mičák Jozef, Scheerová Karla, Szépe Peter, Plank Lukáš
Cesk Patol. 2018 Summer;54(3):137-142.
Recent studies on check-point inhibitor therapy, which seems to improve the prognosis of patients with advanced non-small cell lung carcinoma increase the importance of immunohistochemical analyses of the programmed-death receptor and of its ligand, PD-L1 protein.
In our study we present results of PD-L1 immunohistochemical tumor cell expression in a series of 325 lung carcinoma patients biopsies, using the clone 22C3 (and DAKO Link 48 immunostainer). Evaluation of the expression using tissue proportion scoring system allowed to distinguish negative cases (either 0 % or < 1 % of positive tumor cells) versus positive cases in the categories 1-9 %, 10-49 % and ≥ 50 % of positive tumor cells.
In association to histopathologic parameters we observed similar rates of positive expression in patients with adenocarcinoma types (47,8 % of all the cases) as well as with squamous cell carcinomas (44,4 %). Within these histological categories, the rates of positivity were similar also in patients with small versus large (resectional) biopsies. In the biopsies of patients with adenocarcinoma we identified differences in the PD-L1 protein expression associated with its histological subtype. In the cases with predominant lepidic pattern the PD-L1 positivity was present in 18,8 %, with predominant acinar or papillary pattern in 40,8 % and in cases with predominant solid or micropapillary component in 74,1 % of the cases resp. Keratinizing squamous cell carcinomas were positive in 38,5 % and non-keratinizing in 53,8 % of all the cases. The hiqhest incidence of an extensive posivity was observed in sarcomatoid carcinoma type.
Immunohistochemically verified PD-L1 protein expression represents a broadly accepted predictive biomarker for immunotherapy of NSCLC patients. The indicated differences of the expression among various NSCLC types and subtypes require to be verified in larger cohorts of patients in relation with clinical parameters to demonstrate whether it could be plausible to use the PD-L1 expression in a role of a negative prognostic parameter.
近期关于检查点抑制剂疗法的研究似乎改善了晚期非小细胞肺癌患者的预后，这增加了对程序性死亡受体及其配体PD-L1蛋白进行免疫组化分析的重要性。
在我们的研究中，我们展示了使用克隆22C3（和DAKO Link 48免疫染色仪）对325例肺癌患者活检组织进行PD-L1免疫组化肿瘤细胞表达的结果。使用组织比例评分系统对表达进行评估，可区分阴性病例（阳性肿瘤细胞为0%或<1%）与阳性病例，阳性病例分为阳性肿瘤细胞占1-9%、10-49%和≥50%的类别。
与组织病理学参数相关，我们观察到腺癌类型患者（占所有病例的47.8%）和鳞状细胞癌患者（44.4%）的阳性表达率相似。在这些组织学类别中，小活检与大（切除）活检患者的阳性率也相似。在腺癌患者的活检中，我们发现PD-L1蛋白表达与其组织学亚型相关。以鳞屑样为主型的病例中，PD-L1阳性率为18.8%，以腺泡或乳头为主型的病例中为40.8%，以实体或微乳头成分为主型的病例中为74.1%。所有病例中，角化型鳞状细胞癌阳性率为38.5%，非角化型为53.8%。肉瘤样癌类型中观察到广泛阳性的发生率最高。
免疫组化验证的PD-L1蛋白表达是NSCLC患者免疫治疗广泛接受的预测生物标志物。各种NSCLC类型和亚型之间表达的差异表明，需要在更大的患者队列中结合临床参数进行验证，以证明将PD-L1表达用作阴性预后参数是否合理。
