Biomarkers are the molecules that indicates presence of disease or some of its characteristics. Diagnostic tests are measure biomarkers in blood or tissue specimens. Biomarkers can be any type of molecule, but most of them existing cancer diagnostic tests in blood (e.g., PSA for prostate cancer) measure proteins.
Blood test for colorectal cancer?
Only about half of the people who should get colonoscopies actually get the test. Although the colonoscopy is very safe, there is a small risk of damage to the colon. Some people put off by invasive nature of the procedure and by the bowel prep, which uses strong laxatives to clear the colon for the exam. Evidence of cancer, precancer or small polyps are detected in less than 20% of people who have colonoscopies. The purpose of blood test for early stage colorectal cancer is more efficiently identify those with colon cancer biomarkers in their blood.
A blood test for cancer
The theory behind the blood test for cancer is that cells in the growing cancer will release some proteins into the blood. Such proteins could serve as biomarkers detected by a blood test. Certain cancers release protein molecules into the blood. However, none of these markers detect the early stage cancers very well. We suspect that the other proteins or combinations of several proteins in blood could provide more sensitive, accurate indication of early stage cancers.
How biomarkers identify the early stage colorectal cancers?
Collect the colon tissue from people who undergo colonoscopies or colon cancer surgery. We have collected the samples of colon cancers, precancers, polyps and the normal tissues and analyzed their proteins to determine which are most highly characteristic of cancers. We have identified the several dozen biomarker “candidates”, which are present at much higher levels in the cancers. These candidates are being evaluated identify which are measurable in blood and are present at higher levels in people with colorectal cancers and precancers. Biomarker candidates are most strongly associated with cancer will be evaluated further as components of a new test for early stage cancers.