Expression Of TS Is Associated With Efficacy And Prognosis Of Pemetrexed-containing Chemotherapy For Non-small Cell Lung Cancer:a Meta-analysis

ObjectiveThe non-small-cell lung cancer (NSCLC) patients were treated with pemetrexed as the first-line therapy regimen in Asian region generally. The objective of this analysis was to appraise the association between the expression of TS and clinical efficacy of pemetrexed-based chemotherapy in NSCLC patients and evaluate prognostic and predictive significance of tumor TS level in NSCLC patients in Asian region.MethodsElectronic searches were performed for relevant studies in PubMed, Cochrane Library databases and Chinese Biomedical Literature Database and reference lists of retrieved studies. We systematically identified articles in patients with NSCLC treated with pemetrexed investigating the level of TS in Asian region (last search date:31, October,2015). We performed a Meta-analysis of the results by the Stata 12.0.ResultsSixteen studies were included in the meta-analysis, including 1033 patients. Better response usually appeared in NSCLC patients with a lower expression of TS in Asian region (OR= 0.390,95%CI 0.275-0.553, P=0.001). This analysis also showed that the patients with low TS expression had statistically significantly longer PFS and OS than those with high TS (PFS:HR=0.565,95%CI 0.451-0.706, P<0.001. OS:HR=0.453, 95%CI 0.288-0.714, P=0.001).Furthermore, when we only analyzed the association between the expression of TS and clinical efficacy of pemetrexed as the first-line chemotherapy in Asian NSCLC patients, we also found that there was a significant association between TS expression and the ORR(Objective Response Rate), the PFS(Progress-free survival) and the OS(Overall survival) of pemetrexed-based chemotherapy for Asian NSCLC.ConclusionLow/negative TS expression was significantly associated with higher objective response rate, longer progress-free survival and longer overall survival for NSCLC patients receiving pemetrexed-based chemotherapy as the first-line therapy regimen in Asian region.Hence, TS may be a potential predictor of sensitivity to pemetrexed-based chemotherapy in NSCLC. Large randomized clinical trails are warranted to elucidate the predictive and prognostic value of TS in the well-defined subgroups of NSCLC patients in Asian region.