预后和存活率可被使用化学疗法改善对于部分晚期 NSCLC患者来讲，但较

The prognosis and survival rate can be improved by chemotherapy for some patients with advanced NSCLC, but more obvious adverse reactions will also occur [11]. <br><br>The combined treatment plan, however, is superior to single chemotherapy and has the advantages of high safety and low side effects [12]. <br><br>In recent years, as the role of immune mechanisms in tumorigenesis and development has been continuously clarified, new immunotherapy targets have gradually become clear. <br><br>Some researches believe that [13] that in the process of tumor occurrence and progression, cellular immune deficiency may cause tumor cells to avoid the immune system, and then escape, resulting in the reduction or disappearance of the therapeutic effect of anti-tumor drugs. <br><br><br>At present, targeted drugs and immunological drugs are recommended by an increasing number of lung cancer diagnosis and treatment guidelines for the treatment of advanced non-small cell lung cancer to benefit patients [14, 15]. <br><br>Unlike targeted drugs that directly attack tumor cell targets, the purpose of immunotherapy is mainly to regulate the patient's autoimmune state to achieve the purpose of eliminating tumor cells. <br><br>PD-1 is mainly expressed on the surface of immune cells, while PDL-1 is mainly expressed on the surface of tumor cells. The combination of the two leads to immune escape of tumor cells by activating signal pathways in immune cells. The study by He et al. suggested that PD-1 has the effect of suppressing cellular immunity, and blocking by PD-1/PD-L1 can increase the killing effect of TIL [16]. <br><br>Whether PD-L1 is positive in the tumor microenvironment can be used as an indicator of the effect of immunotherapy [17].

Prognostic and survival rates can be improved by chemotherapy for some patients with advanced NSCLC, but more obvious adverse reactions can also occur.<br><br>The combination therapy, however, is superior to single chemotherapy and has the advantages of high safety and small side effects.<br><br>In recent years, with the role of immune mechanism in tumor occurrence and development has been constantly clarified, the target of new immunotherapy has gradually become clear.<br><br>Some studies have suggested that in the course of tumor occurrence and progression, cellular immunodeficiency may cause tumor cells to avoid the immune system and then escape, leading to the reduction or even disappearance of the effect of anti-tumor drug therapy.<br><br>Currently, targeted and immunologic drugs are recommended by a growing number of lung cancer guidelines for the treatment of advanced non-small cell lung cancer for the benefit of patients.<br><br>Unlike targeted drugs, which directly attack tumor cell targets, immunotherapy aims to regulate the patient's autoimmune status in order to remove tumor cells.<br><br>PD-1 is expressed mainly on the surface of immune cells, while PDL-1 is expressed mainly on the surface of tumor cells, and when combined, the two lead to immune escape of tumor cells by activating the signaling pathway within immune cells. He et al.'s research suggests that PD-1 has the effect of suppressing cellular immunity, and that blocking by PD-1/PD-L1 can increase the lethal effect of TIL.<br><br>Whether PD-L1 is positive in tumor micro-environment can be used as a judgment index of immunotherapy effect.

The prognosis and survival rate can be improved by chemotherapy. For some patients with advanced NSCLC, obvious adverse reactions may also occur [11].<br>However, the combination therapy is superior to single chemotherapy and has the advantages of high safety and small side effects [12].<br>In recent years, with the role of immune mechanism in tumorigenesis and development has been continuously clarified, new immunotherapy targets are also gradually clear.<br>Some studies suggest that [13] in the process of tumorigenesis and progression, cellular immune deficiency may cause tumor cells to evade the immune system, and then escape, leading to the reduction or even disappearance of the therapeutic effect of anti-tumor drugs.<br>At present, targeted drugs and immune drugs are recommended by an increasing number of lung cancer diagnosis and treatment guidelines for the treatment of advanced non-small cell lung cancer, so as to benefit patients [14,15].<br>Different from targeting drugs directly attacking tumor cell targets, the main purpose of immunotherapy is to regulate the patient's autoimmune state to achieve the purpose of clearing tumor cells.<br>PD-1 is mainly expressed on the surface of immune cells, while PDL-1 is mainly expressed on the surface of tumor cells. The combination of PD-1 and PDL-1 can lead to immune escape of tumor cells by activating the signal pathway in immune cells. Studies by he et al. Suggest that PD-1 can inhibit cellular immunity, and the killing effect of TIL can be increased by blocking PD-1 / PD-L1 [16].<br>Whether PD-L1 is positive in tumor microenvironment can be used as an indicator to judge the effect of immunotherapy [17].<br>