Study On The Changes Of Tumor Volume In Patients With Non-small Cell Lung Cancer Treated With Icotinib

Objective:This research was to investigate the regular pattern variation of tumor volumes of advanced Non-Small Cell Lung Cancer(NSCLC)patients harboring Epithelial growth factor receptor(EGFR)gene mutation before and after treating with targeting treatment of epidermal growth factor receptor tyrosine kinase inhibitor(EGFR-TKI),then followed-up and further analyzed the prognostic value of the Tumor Volume Shrinkage Rate(TSR)for Progression-Free Survival(PFS)in Patients with Non-Small Cell Lung Cancer.Methods:Between May 2013 and July 2016,37 cases of advanced NSCLC with EGFR gene mutation were enrolled for treatment with icotinib in Qingdao municipal hospital.Collected chest computed tomography(CT)images before and after targeting therapy retrospectively and used volume measurement software,TPS,to measured primary tumor volume respectively.Then the absolute and relative tumor volume changes of the NSCLC patients before and after targeting treatment were analyzed by paired sample comparison symbol Wilcoxon Rank test.We calculated the Tumor Volume Shrinkage Rate(TSR)by measuring the volume of the main mass on computed tomography before,and 2 months after,icotinib therapy.TSR =(V0-V2)/V0×100 %.Progression-Free Survival(PFS)was measured based on Response Evaluation Criteria in Solid Tumors(RECIST)criteria.The Kaplan-Meier method for progression free survival analysis,Log-rank tested comparison between median progression free survival difference,adopted the Cox proportional risk model for multiple factors survival analysisResults:The absolute tumor volumes(V0)and the relative tumor volume(V0/V0)of patients with NSCLC before targeting treatment were 29.3540(12.0362,69.4110)and 1,respectively.The absolute tumor volumes(V1)and the relative tumor volume(V1/V0)of patients with NSCLC 1 month after targeting treatment were 20.7425(7.2755,47.1035)and 0.7601(0.4167,0.8901),respectively.And there was statistically significant difference between V0 and V1(Z =-3.713,P < 0.001),V0/V0 and V1/V0(Z =-3.836,P< 0.001);The absolute tumor volumes(V1)and the relative tumor volume(V1/V0)of patients with NSCLC 1 month after targeting treatment were 20.7425(7.3435,45.9160)and 0.7533(0.4167,0.8901)respectively.The absolute tumor volumes(V2)and the relative tumor volume(V2/V0)of patients with NSCLC 2 months after targeting treatment were 15.3510(5.6750,34.6363)and 0.5681(0.3900,0.7704),respectively.And there was statistically significant difference between V1 and V2(Z=-2.697,P=0.007),V1/V0 and V2/V0(Z=-3.111,P=0.002),but the differences between three other months(from 3months to 6 months)had no statistically significant differences(P>0.05).32 cases of 37 patients were calculating the average Tumor Volume Shrinkage Rate(TSR)was 36%,selecting 35% as the cut-off.The m PFS was 9 months.Single factor analysis found that the smoking history and the first-line treatment of the targeted therapy,TSR were factors influencing the PFS(P<0.05).For patients who had larger TSR,non-smoking and those who received first-line targeted treatment had significantly longer m PFS,but Cox multivariate analysis was no significant statistical difference(P>0.05).Conclusion : The average primary tumor volume of the NSCLC patients harboring EGFR gene mutation is obviously reduced 1 and 2 months after TKI targeting treatment and remained stable from 3 to 8 months.For patients who had larger TSR had significantly longer m PFS,early tumor volume regression rate may be an important factors for PFS.