Objective To investigate the relationship between the expression of RRM1 and ERCC1 and the efficacy of chemotherapy in stage ⅢB/Ⅳ non-small cell lung cancer(NSCLC)patients treated by gemcitabine/cisplatin chemotherapy(GP regimen).Methods One hundred and thirty-five cases of stage ⅢB/Ⅳ NSCLC patients were included.Bronchoscopy tumor biopsies or lung puncture tumor biopsies were detected by immunohistochemical staining.The patients were treated by at least 4 cycles of GP regimen.The relationship between the e...