Albumin/Globulin Ratio In Patients With Extensive-stage Small-cell Lung Cancer

Objective: Several studies have shown that albumin/globulin ratio(AGR)is associated with the prognosis of patients with various types of malignancies,but it has rarely been reported in small cell lung cancer.This dissertation aims to investigate whether AGR was independently related to prognostic value in patients with extensive-stage small-cell lung cancer after adjusting other covariates.Methods: A medical data of 127 patients with extensive-stage small-cell lung cancer who were administrated to Guangxi Medical University Affiliated Tumor Hospital in China from November 2009 to September 2019 was enrolled in this study.The target independent variable and the dependent variable were AGR measured at baseline and overall survival,respectively.Covariates involved in this study included age,sex,smoking history,Eastern cooperative oncology group –performance status(ECOG-PS),neutrophil/lymphocyte ratio(NLR),lactate dehydrogenase(LDH),hemoglobin(Hb),sum of metastatic organs,sum of treatment lines,sum of first-line treatment cycles,history of thorax radiotherapy and brain radiotherapy.The association of AGR and the risk of death was examined by Cox regression models.Kaplan–Meier method showed the correlation between AGR and overall survival(OS).A two-tailed p<0.05 was considered statistical significance in all analyses.Results:1.The median of AGR is 1.27,which was used as cut-off value of AGR in this study.There were no statistically significant differences in the context of age,gender,smoking history,ECOG-PS,NLR,Hb,sum of metastatic organs,sum of treatment lines,sum of first-line treatment cycles,chest radiotherapy and brain radiotherapy between the AGR<1.27 group and the AGR≥1.27 group(P>0.05).The ratio of patients with LDH≥123 in AGR<1.27 group was significantly higher than that in AGR<1.27 group(P =0.020).2.In the univariate analysis,the risk of death in patients with AGR≥1.27 was reduced by 39%(HR=0.61,95%CI 0.40-0.92,P=0.0186)compared with those with AGR<1.27.A high level of LDH was associated with poor prognosis(HR=2.09,95%CI 1.35-3.24,P=0.0009).Patients with only one organ with distant metastasis(HR=1.74,95%CI 0.94-3.22,P=0.0796)and 2 or more(HR=2.59,95%CI 1.38-4.89,P=0.0032)had significantly higher risk of death compared with patients without distant metastasis.3.After adjusting for confounder factors,Cox proportional risk model found that compared with the group with AGR<1.27,the risk of death in the group with AGR≥1.27 was reduced by 39%(HR=0.61,95%CI 0.40-0.92,P=0.0186).For each additional unit of AGR,the risk of death was reduced by91%(HR=0.09,95% CI 0.03-0,29,P<0.0001).In the trend test analysis,patients were grouped into three groups according to their AGR levels.Compared with group T1,the hazard ratio of group T2 was 0.68(HR=95%CI 0.32-1.43,P=0.3106),and that of group T3 was 0.27(95%CI 0.14-0.53,P=0.0001).The trend test P values(0.0385 and 0.0001,respectively)of the unadjusted and adjusted models were statistically significant.4.In the adjusted smooth curve fitting and threshold effect analysis,it was found that there was a significant negative linear correlation between AGR and death risk.The effect size and confidence interval were 0.20(0.07,0.58),respectively.5.Kaplan-Meier curve showed that the median OS of group AGR<1.27 and group AGR ≥ 1.27 were 10.9 months and 13.9 months,respectively(log-rank P=0.017).The 1-year survival rate was 30.43% and 50% in the AGR<1.27 group and AGR≥1.27 group,respectively.The 2-year survival rate was 4.38% and 12% and the 5-year survival rate was 0 and 4.48% in the AGR<1.27 group and AGR≥1.27 group,respectively.4.Subgroup analysis showed that AGR had a stronger predictive ability in elderly,men,smokers,ECOG-PS 0-1 subgroup,and patients who only with one metastatic organ,only received first-line treatment,received first-line treatment for more than 4 cycles,and did not receive radiotherapy for chest or brain.Conclusion:1.AGR can be used as an independent factor for predicting the overall survival of patients with ES-SCLC.2.Patients with AGR≥1.27 at baseline had longer OS.