文章：

乳腺癌中肿瘤浸润淋巴细胞（TILS）与PD-L1表达：病理学视角下的现有证据及预后意义综述

Tumor Infiltrating Lymphocytes (TILS) and PD-L1 Expression in Breast Cancer: A Review of Current Evidence and Prognostic Implications from Pathologist’s Perspective

原文发布日期：8 September 2023

DOI: 10.3390/cancers15184479

类型: Article

开放获取: 是

英文摘要：

With the rise of novel immunotherapies able to stimulate the antitumor immune response, increasing literature concerning the immunogenicity of breast cancer has been published in recent years. Numerous clinical studies have been conducted in order to identify novel biomarkers that could reflect the immunogenicity of BC and predict response to immunotherapy. In this regard, TILs have emerged as an important immunological biomarker related to the antitumor immune response in BC. TILs are more frequently observed in triple-negative breast cancer and HER2+ subtypes, where increased TIL levels have been linked to a better response to neoadjuvant chemotherapy and improved survival. PD-L1 is a type 1 transmembrane protein ligand expressed on T lymphocytes, B lymphocytes, and antigen-presenting cells and is considered a key inhibitory checkpoint involved in cancer immune regulation. PD-L1 immunohistochemical expression in breast cancer is observed in about 10–30% of cases and is extremely variable based on tumor stage and molecular subtypes. Briefly, TNBC shows the highest percentage of PD-L1 positivity, followed by HER2+ tumors. On the other hand, PD-L1 is rarely expressed (0–10% of cases) in hormone-receptor-positive BC. The prognostic role of PD-L1 expression in BC is still controversial since different immunohistochemistry (IHC) clones, cut-off points, and scoring systems have been utilized across published studies. In the present paper, an extensive review of the current knowledge of the immune landscape of BC is provided. TILS and PD-L1 expression across different BC subtypes are discussed, providing a guide for their pathological assessment and reporting.

摘要翻译： 

随着能够刺激抗肿瘤免疫反应的新型免疫疗法的兴起，近年来关于乳腺癌免疫原性的文献日益增多。为识别能够反映乳腺癌免疫原性并预测免疫治疗反应的新型生物标志物，已开展了大量临床研究。在此背景下，肿瘤浸润淋巴细胞已成为乳腺癌抗肿瘤免疫反应的重要免疫学生物标志物。在三阴性乳腺癌和HER2阳性亚型中更常见肿瘤浸润淋巴细胞，其水平升高与对新辅助化疗的更好反应及生存改善相关。PD-L1是一种表达于T淋巴细胞、B淋巴细胞和抗原呈递细胞的1型跨膜蛋白配体，被认为是参与癌症免疫调节的关键抑制性检查点。在乳腺癌中观察到PD-L1免疫组化表达的比例约为10-30%，且根据肿瘤分期和分子亚型存在极大差异。简而言之，三阴性乳腺癌的PD-L1阳性率最高，其次是HER2阳性肿瘤。而在激素受体阳性乳腺癌中，PD-L1表达较为罕见（0-10%）。由于已发表研究中采用了不同的免疫组化克隆、临界点和评分系统，PD-L1表达在乳腺癌中的预后作用仍存在争议。本文对当前乳腺癌免疫景观的认知进行了全面综述，探讨了不同乳腺癌亚型中肿瘤浸润淋巴细胞和PD-L1的表达特征，为其病理评估和报告提供了指导。

原文链接：

Tumor Infiltrating Lymphocytes (TILS) and PD-L1 Expression in Breast Cancer: A Review of Current Evidence and Prognostic Implications from Pathologist’s Perspective