Pretreatment Serum Lactate Dehydrogenase Level As An Independent Prognostic Factor Of Nasopharyngeal Carcinoma

Background: To analyze the prognostic value of baseline lactate dehydrogenase(LDH)among nasopharyngeal carcinoma(NPC) patients treated with intensity-modulated radiation therapy(IMRT), and to evaluate the potential application of LDH in monitoring treatment efficacy dynamically.Methods: From June 2005 to December 2010, 1188 non-metastatic NPC patients underwent IMRT with or without chemotherapy were reviewed. Univariate and multivariate analysis were performed to evaluate the predicting value of baseline LDH.Wilcoxon signed-rank test was used to analyze the difference between baseline and post-radiotherapy LDH, and to compare post-radiotherapy LDH and those when distant failure occurred.Results: Patients with elevated LDH had significant inferior survivals, in terms of overall survival(70.0% vs. 83.2%, p=0.010), disease-specific survival(71.1% vs.85.7%, p=0.002) and distant metastasis-free survival(71.1% vs. 83.4%, p=0.009), but not correlated with locoregional relapse-free survival(p=0.275) or progression-free survival(p=0.104). Subgroup analysis demonstrated this predicting effect more significant with advanced stage. Sixty-five post-radiotherapy LDH data were available from the 90 patients with high LDH at initial diagnosis, and they fell in all the 65 patients, with 62 cases(95.4%) fell down within the normal value. Eighty-seven of the208 patients who experienced subsequent distant failure possessed available LDH at that time. Among them, 69 cases(79.3%) increased when compared to the post-radiotherapy LDH.Conclusions: Pretreatment LDH is a simple, cost-effective biomarker that could predict survivals and could be used in individualized treatment. It is also a potential biomarker that might reflect tumor burden and be used to monitor therapy efficacy.