The detection of tissue PD-L1 immunohistochemistry in NSCLC has an important role in guiding for the treatment of immune detection point.Radiation therapy can enhance the effect of immunotherapy,but radiation dose and timing are waiting to be solved. At the same time,tissue detection is time-consuming and laborious, liquid biopsy can reflect the information of tumor tissue,PD-L1 mRNA in plasma exosomes (pExo) is expected to be simple, rapid, non-invasive means of detection. The project is planned to explore the consistency analysis of PD-L1 expression level detected in advanced non-small cell cancer patients' cancer tissues and pExo before and after radiotherapy.The investigators have designed five kinds of radiation-division with bioequivalent doses, and detected the expression levels of PD-L1 in pExo after 24h, 48h of each stage of radiotherapy.PD-L1 mRNA levels in pExo detected at different time points,by using variance analysis of repeated measures design information.Probing the best timing and manner of radiotherapy division which can make PD-L1 express more,guiding clinical practice of radiotherapy combining with immunotherapy.

Radiation therapy can enhance the effect of immunotherapy,but radiation dose and timing are waiting to be solved. At the same time,tissue detection is time-consuming and laborious, liquid biopsy can reflect the information of tumor tissue,PD-L1 mRNA in plasma exosomes (pExo) is expected to be simple, rapid, non-invasive means of detection. The project is planned to explore the consistency analysis of PD-L1 expression level detected in advanced non-small cell cancer patients' cancer tissues and pExo before and after radiotherapy.The investigators have designed five kinds of radiation-division with bioequivalent doses, and detected the expression levels of PD-L1 in pExo after 24h, 48h of each stage of radiotherapy.PD-L1 mRNA levels in pExo detected at different time points,by using variance analysis of repeated measures design information.Probing the best timing and manner of radiotherapy division which can make PD-L1 express more,guiding clinical practice of radiotherapy combining with immunotherapy.

Inclusion Criteria:

1. Pathological histology and/or cytology confirmed NSCLC;
2. Based on AJCC Cancer Staging, IIIA, IIIB, IV lung cancer patients with NSCLC;
3. PS 0-2;
4. Expected survival > 3 months;
5. Age 18~75 years old;
6. The function of lung, liver, kidney, bone marrow was normal;
7. The patients had not received radiotherapy for previous primary tumor and metastases;
8. At least accept 2-4 cycles of chemotherapy,not disease progression after chemotherapy,start radiotherapy in two weeks after the last cycle of chemotherapy;
9. Wild-type EGFR;
10. Sensitive mutant EGFR, but refused to targeted therapy;
11. In line with the indications of radiotherapy and accept it;
12. Voluntarily enrolled to participate in,better compliance, cooperate with experimental observations, and sign informed consent.

Exclusion Criteria:

1. Vital organs (e.g., heart, liver, kidney) have serious dysfunction;
2. Patients with other malignancies;
3. Patients with a history of autoimmune disease;
4. The patients are pregnant and lactating (Women of childbearing age need to check the pregnancy test);
5. In the activity of acute or chronic infectious diseases;
6. Patients with a clear history of drug allergy or allergic genus;
7. Patients with participating in other clinical trials at the same time;
8. Other cases that researchers believe that patients should not participate in the present trial.