Inter-tumor heterogeneity between the primary and lymph node (LN) metastatic lesions in RNA gene expression. (A) Pie chart summarizing intracellular pathways according to KEGG BioSystem with significant inter-tumor differences in RNA gene expression detected (n=154). Highest proportion of genes belonged to the cytokine-cytokine receptor interaction pathway (11.1%), that are associated with crucial aspects of inflammation, tumor immunology and differentiation. (B) Strong correlation (0.7≤r<1) and non-correlation (−0.3≤r<0.3) in relative RNA gene expression according to the main molecular cellular components (encoding products). Asterisk, significant (P<0.05) differences in relative gene expression (genes in importance in transcription factors, receptors and signaling, extracellular and cell adhesion).