Abstract: Objective In patients with non-small cell lung cancer(NSCLC)undergoing radical surgery,there were still many inevitable recurrences and distant metastases,even after systemic postoperative adjuvant chemotherapy.At the same time,many patients were in the stage Ⅳ at the time of initial treatment.The aims of this study were to investigate and compare the first-line chemotherapy(First-line Chemotherapy at Recurrence Post-adjuvant Chemotherapy,FCRPC)in NSCLC patients with distant metastasis after adjuvant chemotherapy with initial treatment at the phase Ⅳ of NSCLC patients with first-line chemotherapy(Initial First-line Chemotherapy,IFC).Methods A total of 603 patients with distant metastatic NSCLC were collected in this study.Among them,73 of them were FCRPC and 530 of them for IFC.Statistical methods for propensity score matching were used to balance the clinical features between FCRPC and IFC groups.Chi-square test was used to compare the short-term efficacy between FCRPC and IFC groups.Survival analysis was performed using regression analysis and Kaplan-Meier analysis.Results There was no significant difference in Objective response rate(ORR)and disease control rate(DCR)between FCRPC and IFC groups in NSCLC patients with distant metastases(ORR rate:27.46% in the FCRPC group,24.7% in the PFC group,P=0.851 and DCR rate:78.1% in the FCRPC group,65.6% in the PFC group,P=0.140).There was also no significant difference in the median progression-free survival(9.8 months in the FCRPC group and 8.5 months in the PFC group,P=0.337)and median overall survival(20.0 months in the FCRPC group and 14.4 months in the PFC group,P=0.087).Conclusion There is no significant difference in the prognosis of first-line chemotherapy between NSCLC patients with distant metastases and with initial treatment at the stage Ⅳ after adjuvant chemotherapy.

Key words: Non-small cell lung cancer, Distant metastasis, First-line chemotherapy, Survival analysis, Efficacy evaluation