Serum CCL2 and serum TNF-α - Two new biomarkers predict bone invasion, post-treatment distant metastasis and poor overall survival in nasopharyngeal carcinoma

Purpose: To evaluate the prognostic potential of serum CCL2 (sCCL2) and serum TNF-alpha (sTNF-alpha) in nasopharyngeal carcinoma (NPC) before treatment by analysing the expression of these two markers. Experimental design: Both sCCL2 and sTNF-a were prospectively detected in 297 NPC patients with enzyme-linked immunosorbent assay (ELISA) before treatment. The correlations between sCCL2 level or sTNF-alpha level and patient's survival were evaluated. Results: For sCCL2, the 5-year overall survival (OS) and 5-year distant metastasis-free survival (DMFS) of high expression group and low expression group were 64% versus 81% and 67% versus 84% (P < 0.05), respectively. For sTNF-alpha, the 5-year OS and 5-year DMFS of high expression group and low expression group were 62% versus 79% and 66% versus 82% (P < 0.05), respectively. The 5-year OS and 5-year DMFS for both positive patients, one marker positive patient and both negative patients were 53% versus 77% versus 85% and 58% versus 80% versus 86% (P < 0.05), respectively. Concentrations of sCCL2 and sTNF-a in patients with large skull base invasion were higher than those without or with small skull invasion (P < 0.05). Patients who developed bone metastasis alone after radical treatment had higher pre-treatment concentrations of sCCL2 and sTNF-alpha than those without metastasis (P < 0.001). Multifactorial Cox regression analyses demonstrated that T/N/M classification, chemotherapy, sCCL2 level and sTNF-alpha level were independent predictors of OS and DMFS of NPC patients. Conclusion: High expression levels of sCCL2 and sTNF-alpha predict bone invasion, post-treatment distant metastasis and poor overall survival in NPC patients. (C) 2010 Elsevier Ltd. All rights reserved.