In subgroup analyses, CD68 expression was strongly correlated with CD163 (Pearson correlation r = 0.636, p < 0.001) and VEGF-A (Pearson correlation r = 0.533, p < 0.001) expression, while there was a moderate correlation between CD68 and VEGF-C (Pearson correlation r = 0.329, p < 0.001) expression (Additional file 2: Fig. S2) in adenocarcinoma patients. This evidence concerns the gene VEGFA and adenocarcinoma.