Head and Neck Medical Oncology Unit, Fondazione IRCCS Istituto Nazionale dei Tumori di Milano, Milan, Italy.
Department of Pathology, Fondazione IRCCS Istituto Nazionale dei Tumori di Milano, Milan, Italy.
Oncology. 2019;97(2):112-118. doi: 10.1159/000500246. Epub 2019 May 21.
Recurrent or metastatic (R/M) skin squamous cell carcinoma (sSCC) not amenable of surgery or irradiation may benefit from systemic therapies. Epidermal growth factor receptor (EGFR) inhibitors and, more recently, immune checkpoint blockers (ICBs) showed activity in R/M sSCC. In this study, we aimed at exploring the possible role of PD-L1 expression in predicting response to anti-EGFR agents.
Patients affected by R/M sSCC, treated with pan-HER inhibitor dacomitinib or with platinum-based chemotherapy with cetuximab (CT-cet) from 2010 to 2016, were considered. PD-L1 expression was assessed with immunohistochemistry on tumor cells (TCs) and on microenvironment (TC and tumor-infiltrating lymphocyte [IC] scores, respectively). Prognostic role of PD-L1 and the correlation with response to EGFR inhibitors and survival were analyzed.
Twenty-eight R/M sSCCs were analyzed (19 treated with dacomitinib, 9 with CT-cet). TC and IC were negative in 82 and 45% of cases, respectively; 15% sSCCs were both TC and IC positive. Progression-free survival (PFS) was longer in IC-positive cases (median 7.5 months vs. 2.1 in IC0, p = 0.02). No statistically significant differences were observed between PD-L1 expression and both overall survival and response rates.
PD-L1 expression in microenvironment predicted better PFS. The combination of EGFR inhibitors and ICB could help deepening the knowledge about the interrelations between the EGFR and PD-1/PD-L1 pathways.
无法手术或放疗的复发性或转移性（R/M）皮肤鳞状细胞癌（sSCC）可能受益于系统治疗。表皮生长因子受体（EGFR）抑制剂，以及最近的免疫检查点抑制剂（ICB），在 R/M sSCC 中显示出活性。在这项研究中，我们旨在探讨 PD-L1 表达预测抗 EGFR 药物反应的可能作用。
考虑了 2010 年至 2016 年间接受 pan-HER 抑制剂达克替尼或铂类化疗联合西妥昔单抗（CT-cet）治疗的 R/M sSCC 患者。使用肿瘤细胞（TC）和微环境（TC 和肿瘤浸润淋巴细胞 [IC]评分）的免疫组织化学评估 PD-L1 表达。分析 PD-L1 的预后作用及其与 EGFR 抑制剂反应和生存的相关性。
分析了 28 例 R/M sSCC（19 例接受达克替尼治疗，9 例接受 CT-cet 治疗）。TC 和 IC 分别在 82%和 45%的病例中为阴性；15%的 sSCC 两者均为阳性。IC 阳性病例的无进展生存期（PFS）较长（中位 PFS 为 7.5 个月，IC0 为 2.1 个月，p=0.02）。PD-L1 表达与总生存期和反应率之间未观察到统计学上的显著差异。
微环境中的 PD-L1 表达预测了更好的 PFS。EGFR 抑制剂和 ICB 的联合应用可能有助于加深对 EGFR 和 PD-1/PD-L1 通路之间相互关系的认识。
