During colonoscopy, a physician can visually detect tubular adenomas and remove them at the time of the procedure; waiting until a blood test is “positive” may lead to a scenario where the CRC could have been prevented years beforehand.
It is important to have a detailed discussion with the patient regarding the risks and benefits of these options prior to testing. Physicians should confirm that patients are willing to undergo a colonoscopy if test results return positive. The concept of a false-positive should also be thoroughly explained.
It is important to note to the patient, however, that if the septin-9 test is positive, a colonoscopy is required. If the patient is adamantly against a colonoscopy regardless of the septin-9 result, the test is not worthwhile.
The septin-9 blood test is non-invasive and does not require extended time away from work or anesthesia. Though the septin-9 test is commercially available and approved by the US Food and Drug Administration, it is not yet recommended in any prominent CRC screening guideline.
Finding a more specific and sensitive blood test for CRC detection and/or pre-cancerous lesions will likely be an important future focus of research in both gastroenterology and oncology.
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