免疫检查点抑制剂在PD-L1低表达/阴性晚期NSCLC患者中的治疗现状
Current Status of Immune Checkpoint Inhibitor Therapy in Patients with PD-L1 Low Expression/Negative Advanced NSCLC

肺癌(lung cancer)的组织病理学分为非小细胞肺癌和小细胞肺癌两大类，其中，非小细胞肺癌最为常见，约占肺癌总发病率的85%。非小细胞肺癌(non-small cell lung cancer, NSCLC)是一种病因和发病机制迄今尚未明确的癌症，它主要包括腺癌、鳞癌和大细胞癌。肺癌的治疗根据病人的机体情况，病理学类型(包括分子病理诊断)，侵及范围(临床分期)，采取多学科综合治疗模式，强调个体化治疗。有计划、合理地应用手术、化疗、生物靶向和放射治疗等手段，以期达到根治或最大程度控制肿瘤，提高治愈率，改善病人的生活质量，延长生存期为目的。但对于非小细胞肺癌的患者来说，由于患者常在晚期被诊断，化疗、放疗、靶向治疗及抗血管生成治疗虽然可以改善其预后，但经相关研究发现，NSCLC患者的5年生存率仍不尽人意。在过去的十年中，癌症医学中免疫检查点抑制剂的发现和开发取得了快速进展，癌症免疫治疗取得了重大突破，特别是靶向非小细胞肺癌中程序性细胞死亡蛋白1 (PD-1)和程序性细胞死亡蛋白配体-1 (PD-L1)抑制剂的出现极大地改变了肿瘤治疗的格局。在本综述中，我们重点关注NSCLC中PD-L1低表达/阴性患者的免疫治疗效果，就近些年来晚期NSCLC患者PD-L1低表达/阴性的治疗现状和临床研究进行综述。
The histopathology of lung cancer is divided into two categories: non-small cell lung cancer and small cell lung cancer, among which, non-small cell lung cancer is the most common, accounting for about 85% of the total incidence of lung cancer. Non-small cell lung cancer is a type of cancer whose etiology and pathogenesis have not been clarified so far, and it mainly includes adenocarcinoma, squamous carcinoma and large cell carcinoma. The treatment of lung cancer is based on the pa-tient’s body condition, pathological type (including molecular pathology diagnosis) and invasion scope (clinical stage), and adopts a multidisciplinary and comprehensive treatment model, empha-sizing individualized treatment. Surgery, chemotherapy, biologic targeting and radiotherapy should be used in a planned and rational manner to achieve radical cure or maximum tumor control, in-crease the cure rate, improve the patient’s quality of life and prolong the survival period. However, for patients with non-small cell lung cancer, as patients are often diagnosed at an advanced stage, chemotherapy, radiotherapy, targeted therapy and anti-angiogenic therapy can improve their prognosis, but the 5-year survival rate of NSCLC patients is still unsatisfactory as found by relevant studies. In the past decade, the discovery and development of immune checkpoint inhibitors in cancer medicine have made rapid progress and significant breakthroughs in cancer immunothera-py, especially the advent of targeted programmed cell death protein 1 and programmed cell death protein ligand-1 inhibitors in non-small cell lung cancer has dramatically changed the landscape of tumor treatment. In this review, we focus on the effect of immunotherapy in patients with low/negative PD-L1 expression in NSCLC and review the current status and clinical studies on the treatment of advanced NSCLC patients with low/negative PD-L1 expression in recent years.