Prognostic significance of CD163 expression and its correlation with cyclooxygenase-2 and vascular endothelial growth factor expression in cutaneous melanoma

In several cancers, tumor progression is associated with the infiltration of tumor-associated macrophages (TAMs). The aim was to evaluate the prognostic significance of expression of CD163 and CD68 (TAMs' markers) and their correlation with vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) expression in cutaneous melanoma. Diagnostic tissues from 102 patients of cutaneous melanoma were evaluated by immunohistochemistry for their CD68, CD163, VEGF, and COX-2 expression. Correlations between the proteins were then investigated. Clinicopathological features, overall survival (OS), and progression-free survival were analyzed in terms of the expression of these proteins. CD163, but not CD68, expression correlated with VEGF and COX-2 expression. High expression for CD163 was associated with a deeper Breslow thickness and an advanced stage of the disease. High expression of CD163 was associated with lower OS. No significant differences were noted in CD68 expression between the clinicopathological variables and the OS. COX-2 expression was associated with a deeper Breslow thickness and a higher frequency of lymph node involvement. Multivariate analysis revealed that CD163 expression and COX-2 expression were independent prognostic markers of lower survival outcomes. Our data confirmed that CD163 expression provides independent prognostic information in cutaneous melanoma. The correlation of CD163 with VEGF and COX-2 expression suggests various tumor-promoting actions of CD163-positive TAMs.