By Dr. Gary Vukov
Cologuard is a new screening test for colon cancer approved by the FDA and covered by Medicare and some insurance companies.
Colon cancer is found in approximately 6% of the US population and typically begins as small colon polyps. Most polyps and early colon cancers typically do not cause symptoms. Early detection and management typically have better outcomes.
Most individuals are familiar with colonoscopy as a colorectal screening tool. It must be emphasized that a screening test for colon cancer is a test performed on an individual who has no symptoms attributed to the colon (rectal bleeding, altered bowel habit, unexplained anemia or weight loss, abdominal pain, etc). This test involves preparing the colon with various laxatives and using a colonoscope (flexible tube with camera) to inspect the colonic lining for polyps and or cancers. It is recommended that your endoscopist be well trained and experienced with identification of the various types of polyps and various methods of their removal, such as a board certified gastroenterologist. During this examination most polyps can be removed or at least biopsied. Removal of pre cancerous colon polyps (adenomas) has been shown to reduce the incidence of colon cancer. Most colon cancer screening tests are recommended in individuals at the age 50.
Less invasive screening tests include testing of stool for blood and cologuard which includes testing for blood as well as stool DNA. Colon cancer and larger polyps shed cells which contain abnormal DNA. The shedding of cells mixes with stool and passes through the colon. Cologuard includes molecular assays for DNA Mutations and methylation biomarkers that are associated with colorectal neoplasia. Once a non invasive test shows blood and or abnormal DNA than a colonoscopy is ordered to examine the colon to identify the source of the abnormal test.
Cologuard has been reported to pick up 92% of colon cancers and 42% of precancerous polyps. There is a 10% false positive test which means that follow up colonoscopy does not identify a lesion. The test is ordered by your health care provider and the company contacts you. The Kit is sent to you at your home with instructions. Once you completed the kit it picked up by UPS and sent to Exact Sciences Laboratory.
Some of the benefits of this test involve performing it at home without dietary nor medication changes. This is probably not the test for patients with a personal history of colon cancer and or polyp, inflammatory bowel disease (Crohn’s and ulcerative colitis) or family history of colon cancer. Follow-up screening intervals with this test have not been established at this time. Typically the results are available to your health care provider in two weeks. For further information visit www.CologuardTest.com.