Introduction:
Colorguard is a stool test that detects the mutations in the DNA and detects the precancer and cancer from the stool sample. Cologuard is a non-invasive test that can be done at home and sent to the laboratory for analysis. The test should be done every three years.
What Is a Colonoscopy?
A colonoscopy is a gold standard test for diagnosing colon cancer. But it is an invasive test done by a medically qualified professional. The procedure involves inserting a flexible tube with a light and camera attached to it called the colonoscope and introducing it till the end of the colon. Also, if the doctor sees any polyps during colonoscopy, they can remove them at the same time and send them to the lab for further investigation.
What Is the Difference Between Colonoscopy and Cologuard?
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The main difference between a cologuard and a colonoscopy is that colonoscopy is an invasive procedure, whereas a cologuard is a non-invasive procedure. But the colon cannot be visualized in the cologuard as in a colonoscopy.
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The cologuard can miss up to 50 % of precancerous polyps and about 8 % of colon cancers.
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In cologuard, colon cancers are diagnosed and cannot be prevented, whereas colonoscopy can also be prevented.
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A negative stool DNA test should be repeated every three years, whereas a colonoscopy can be done every ten years.
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Cologuard (stool DNA test) is not advised for patients with high risk, like patients with a family history of colorectal cancers, irritable bowel disease, and history of polyps.
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Cologuard does not require any dietary changes whereas, before the colonoscopy, there are certain things to follow as a part of bowel preparation for the procedure.
How to Prepare for a Colonoscopy?
For the colposcopy procedure, the bowel needs to be empty during the procedure. Any residue in the colon can interfere with the images and affect the result. So to empty the colon, the doctor will suggest the following:
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Follow the Diet - A special diet will be advised by the doctor, who needs to be followed. Any solid food item should be avoided a day before the procedure. Clear liquids may be taken. Also, avoid red-colored drinks, which can be mistaken during the colonoscopy as blood. The night before the procedure, after midnight, no solids or liquids will be allowed.
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Laxatives - The doctor will advise taking laxatives either in pill form or syrup form, which should be taken at night before the colonoscopy.
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Adjust the Medications - Inform the doctor about the medications at least a week prior to the procedure, especially medication for hypertension, diabetes, or heart problems. Also, inform the doctor in case one is taking medicines such as Aspirin or other blood thinners like Warfarin which are used to reduce the risk of blood clots or stroke.
What to Expect during Colonoscopy?
During a colonoscopy, the patient is asked to wear a gown, but likely nothing else. Sedation or anesthesia is usually recommended. In most cases, the sedative is combined with pain medication given directly into the bloodstream (intravenously) to lessen any discomfort. The patient will be asked to lie on the exam table to one side, usually with their knees drawn toward the chest. The doctor will insert a colonoscopy into the rectum. The colonoscope is long enough to reach the entire length of the colon and contains a light and a tube (channel) that allows the doctor to pump air, carbon dioxide, or water into the colon. The air or carbon dioxide inflates the colon, which provides a better view of the lining of the colon. When the scope is moved or air is introduced, the patient may feel stomach cramping or the urge to have a bowel movement.
The colonoscope also contains a tiny video camera at its tip. The camera sends images to an external monitor so that the doctor can study the inside of the colon. The doctor can also insert instruments through the channel to take tissue samples (biopsies) or remove polyps or other areas of abnormal tissue. A colonoscopy typically takes about 30 to 60 minutes.
What Are the Risks Associated with Colonoscopy?
A colonoscopy poses few risks. Rarely, complications of a colonoscopy may include:
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A reaction to the sedative used during the exam.
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Bleeding from the site where a tissue sample (biopsy) was taken or a polyp or other abnormal tissue was removed.
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A tear in the colon or rectum wall (perforation).
After discussing the risks of colonoscopy with the patient, the doctor will obtain a signed consent form giving permission for the procedure.
How Is the Cologuard Test Done?
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The Cologuard testing kit for colon and rectal cancer must be ordered by the healthcare provider. It will be sent by mail to the patient’s address. The patient is asked to collect the sample at home and send it back to the lab for testing.
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The Cologuard testing kit will contain a sample container, a tube, preserving liquid, labels, and instructions on how to collect the sample. When the patient is ready to have a bowel movement, use the cologuard testing kit to collect the stool sample.
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Read the instructions that come with the testing kit carefully. The patient is asked to wait until they are ready to have a bowel movement. Collect the sample only when it is possible to ship it within 24 hours. The sample must reach the lab in 72 hours (3 days).
What Are the Risks Associated with Cologuard?
There is no risk involved in taking the sample for the Cologuard test.
Screening tests carry a small risk of:
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False Positives- The test results are abnormal, but the patient does not have colon cancer or premalignant polyps).
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False Negatives- The test is normal, even when the patient has colon cancer).
Conclusion:
A colonoscopy is a medical diagnostic procedure that evaluates the large bowel and is performed by a trained physician. The colonoscope is a long, firm, and flexible plastic tube with a small digital camera and light at one end. A colonoscopy can be performed to look for polyps or abnormal growth and as well as to detect early symptoms such as unexplained diarrhea, abdominal pain, or blood in the stool. Early cancers and polyps can both be removed at the same time. Whereas cologuard is performed by the patient at home with the help of cologuard testing kit. No preparation is needed to perform cologuard at home. When compared, both colonoscopy gives accurate results and is the most reliable.
