Indeed, mutations in the ras oncogene and p53 antioncogene are detectable in 40–60% of colorectal cancers (Bos, 1989; Kinzler and Vogelstein, 1996; Dong et al, 2001; Rengucci et al, 2001; Nishikawa et al, 2002; Smith et al, 2002). This evidence concerns the gene TP53 and colorectal cancer.