TNF and colorectal cancer: Low baseline values, large CVs, and a limited dynamic range in most human samples combined with smaller increases in cytokine concentrations in blood in early vs later stages of colorectal neoplasia may limit the potential of IL-8, TNFα, IL-12p70, GMCSF, and IFNγ as risk indicators for colorectal cancer prevention, although higher concentrations of TNFα in blood have been observed in colorectal adenoma patients compared with healthy individuals (Berghella et al, 1996; Roselli et al, 2003; Kim et al, 2008).