Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Department of Pathology, University of Chicago, Chicago, IL, USA.
Br J Cancer. 2021 Feb;124(3):564-566. doi: 10.1038/s41416-020-01130-x. Epub 2020 Oct 26.
Programmed death-ligand 1 (PD-L1) expression has been described in patients with malignant peritoneal mesothelioma (MPM), but treatment strategies utilising immune checkpoint inhibition are yet to be defined. Here, we examine levels of PD-L1 expression in MPM patients treated with systemic and/or intraperitoneal chemotherapy using tissue from patient tumour biopsies or resections at multiple time points. We found the mean PD-L1 expression was higher in those with a germline mutation and/or those with a higher somatic mutation burden. Moreover, PD-L1 expression was lower in patients who had received prior chemotherapy as compared to the treatment-naive cohort. Twenty patients who received chemotherapy, either systemic and/or peritoneal, between PD-L1 measurements showed marked heterogeneity. Six (30%) patients demonstrated upregulation of PD-L1, while eight (40%) demonstrated downregulation. Heterogeneity in PD-L1 expression in MPM before and after cytotoxic therapies may present an additional consideration when initiating immune checkpoint inhibition in this rare and challenging disease.
程序性死亡配体 1（PD-L1）在恶性腹膜间皮瘤（MPM）患者中已有描述，但利用免疫检查点抑制的治疗策略尚未确定。在这里，我们通过对来自患者肿瘤活检或多次切除的组织，研究了接受全身和/或腹腔化疗的 MPM 患者的 PD-L1 表达水平。我们发现，具有种系突变和/或具有更高体细胞突变负担的患者的 PD-L1 表达更高。此外，与初治队列相比，先前接受过化疗的患者的 PD-L1 表达水平较低。在 PD-L1 测量之间接受了化疗（全身和/或腹腔）的 20 名患者显示出明显的异质性。6 名（30%）患者的 PD-L1 上调，而 8 名（40%）患者的 PD-L1 下调。在接受细胞毒性治疗前后，MPM 中 PD-L1 表达的异质性在启动这种罕见且具有挑战性的疾病的免疫检查点抑制时可能需要额外考虑。
