High expression of chemokine CCL2 is associated with recurrence after surgery in clear-cell renal cell carcinoma

Abstract

PurposeChemokine (C-C motif) ligand 2 (CCL2) is known to recruit monocytes and macrophages to sites of inflammation. Recent studies suggest CCL2 is overexpressed in multiple cancer types and may play a role in the tumor progression. The aim of this study was to assess the association between CCL2 expression and the risk of recurrence after surgery in patients with clear-cell renal cell carcinoma (ccRCC). MethodsThis study included 268 ccRCC patients who underwent nephrectomy at a single institute between 2001 and 2004. Clinicopathologic variables and recurrence-free survival (RFS) were recorded. CCL2 expression levels were evaluated by immunohistochemical staining in tumor tissues. Kaplan-Meier method was applied to compare survival curves. Cox regression models were fitted to analyze the effect of prognostic factors on recurrence-free survival (RFS). Harrell’s concordance index was calculated to assess predictive accuracy. ResultsHigh CCL2 expression was associated with a greater risk of recurrence in ccRCC patients (P<0.001). Multivariate analysis confirmed that CCL2 expression was an independent prognostic factor for RFS (P = 0.045). The predictive accuracy of the Leibovich prognostic score was improved when CCL2 expression was added (0.76 vs. 0.71, P<0.001). Notably, the improvement in prediction was more pronounced in patients with low-risk disease. A nomogram integrating CCL2 expression and pathologic factors was then constructed, which predicted 5- and 10-year RFS well for ccRCC patients. ConclusionsHigh chemokine CCL2 expression is an independent predictor of recurrence in ccRCC patients. Evaluation of CCL2 could help guide postsurgical management for ccRCC patients.