Prognostic value of pretreatment platelet count in lung cancer: a systematic review and meta-analysis

Abstract

Background : The prognostic value of pretreatment elevated platelet count remains controversial in lung cancer patients. We performed the present meta-analysis to determine the precise role of it in these patients. Methods: We performed a multiple search strategy in PubMed database, EMBASE and Cochrane Library to identify eligible studies. Disease-free survival (DFS) /Progress-free survival (PFS)/Time to progress (TTP) and Overall survival (OS) were used as outcomes with hazard ratio (HR) and its 95% confidence intervals (CIs). Heterogeneity among studies and publication bias were also evaluated. Results : A total of 40 studies including 16696 lung cancer patients were eligible in the analysis. Overall, the pooled analysis showed that pretreatment elevated platelet count was associated with poorer OS (HR= 1.54, 95%CI:1.37-1.72, P<0.001) and poorer DFS/PFS/TTP (HR=1.62, 95%CI: 1.33-1.98, P<0.001) in patients with lung cancer compared with normal platelet count. In subgroup analyses, pretreatment elevated platelet count was also associated with poorer OS and DFS/PFS/TTP in most subgroups. There was no evidence of publication bias. Conclusions : This meta-analysis revealed that pretreatment elevated platelet count was an independent predictor of OS and DFS/PFS/TTP in lung cancer patients. Large scale prospective studies and a validation study are warranted.