CEACAM5 and neoplasm: The levels of T cell subsets (CD3+, CD4+, and CD8+), serum tumor markers (squamous cell carcinoma antigen (SCCA), cytokeratin Ig fragment (CYFRA21-1), and serum carcinoembryonic antigen (CEA)), nuclear factor kappa B (NF-κB), protease C (PKC), and mitogen-activated protein kinase (MAPK) mRNA expression between the two groups were compared.