Serum lactate dehydrogenase as a prognostic biomarker in patients with Ewing's sarcoma: a meta-analysis

Purpose: The prognostic value of serum Lactate dehydrogenase (sLDH) in Ewing sarcoma (ES) has been studied worldwide during these years and provided un-uniformed conclusions. Methods: Comprehensive literature was selected from PUBMED, EMBASE and WEB OF KNOWLEDGE. Clinical studies which reported analysis of survival data about sLDH in ES were included. Stata 12.0 was used for performing a meta-analysis on evaluating the relation between LDH and clinical staging, overall survival (OS) and disease free survival (DFS). Results: A total of 13 articles, including 2395 patients who satisfied inclusion criteria were analyzed. The result showed that high concentration of sLDH was related to a bad OS (HR = 1.93, 95% CI 1.68-2.22) and a extremely worse DFS (HR = 5.96, 95% CI 3.37-10.54). The subgroup analysis on different location of ES suggested the prognosis of extremity group (HR = 1.91, 95% CI 1.67-2.34) was better than axial skeleton group (HR = 2.03, 95% CI 1.67-2.48). Another subgroup analysis suggested that it was even worse prognosis (HR = 2.11, 95% CI 1.74-2.55) when distant metastasis percents > 30% than distant metastasis percents < 30% (HR = 1.96, 95% CI 1.69-2.28). Conclusions: Our findings suggest that sLDH can be regarded as a poor prognostic maker for ES and may represent a important new therapeutic target.