To propose the most sensitive and specific hypermethylated DNA promoter regions for CRC detection, a review of the literature currently available will be undertaken. The following search criteria (MeSH terms) will be used: "colorectal neoplasm", "DNA methylation or CpG islands", "tumour or stool sample or blood or serum or plasma", "real time PCR or microarray analysis or genome sequencing or biopsy or blood analysis". Based on this review a literature review will be written: "DNA Methylation in Blood and Stool as a Screening and Prognostic Marker for Colorectal Cancer".