Colorectal Cancer Screening
screening must focus on one specific DNA defect. Current research indicates that methylation of the DNA molecule at certain sites is a common defect in colorectal cancer. One study found that testing for methylation at the SFRP2 location provided a sensitivity of 90% in detecting cancer in patients.
The cyclooxygenase 2 (COX-2) enzyme is commonly overexpressed in colorectal tumors. The formation of this enzyme is directed by COX-2 messenger RNA. A group of researchers devised a fecal COX-2 messenger RNA assay, and found a 90% sensitivity in detecting colorectal cancer. Although promising, fecal DNA or RNA testing is still in the early stages of development.
References
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