What is a colon cancer screening?
Colorectal cancer is the third most commonly diagnosed cancer. However, it’s also one of the most common preventable cancers. The colon and rectum make up the large intestine, which absorbs water and some nutrients from digested food and stores solid waste until it is expelled from the body.
A colon cancer screening is the process of looking for polyps and cancerous growths on the inner wall of the colon and rectum when no gastrointestinal symptoms of the disease are present. A polyp is a noncancerous growth in the colon. Some of these may become cancerous later. Early detection and removal of colorectal polyps and malignant tumors can prevent complications and death due to colon cancer.
The board-certified gastroenterologists at GI Alliance routinely perform colon cancer screenings and encourage all patients to undergo these screenings at age 45. To arrange for a screening, please contact a GI Alliance office in your community.
What are the benefits of colon cancer screenings?
Routine screenings for colon and rectal cancer are imperative to your general and gastrointestinal health. While there are several screening strategies, like stook testing, a colonoscopy is the only colorectal prevention strategy. Several benefits of colorectal cancer screenings involve:
- Can be a life-saving exam
- Potentially detect colon or rectal cancer early on
- Identify and excise polyps in the colon and rectum
- Potentially prevent the development of colon cancer
- Detect other gastrointestinal issues, like inflammatory bowel disease
Cancer of the colon may not show signs or symptoms until it advances. Having screenings periodically can help your doctor identify any concerns or conditions as soon as possible.
What colon cancer screening options are available?
People should talk to their GI doctor about when to go for the screening and what tests to have. One or more of the following tests may be used for colon cancer screening:
- Flexible sigmoidoscopy: A sigmoidoscope is used to view the inside of the rectum and lower colon. A finger-sized thick tube with a camera at the end is inserted from the rectum, and images of the inner wall of the rectum and part of the colon can be seen on the monitor. It can be used to take a biopsy of the polyp or tumor and remove some polyps. However, a colonoscopy needs to be done to view the whole colon and remove all polyps or tumors. It is fairly safe but has a small risk of bowel tear, bleeding, and infection.
- Colonoscopy: A colonoscope is similar to a sigmoidoscope but is longer and is used to examine the inner wall of the whole colon. It is inserted from the rectum, and the doctor can see the images of the entire colon on the monitor. Special surgical tools can be passed through the colonoscope to take a biopsy and remove polyps. Sedation is required. There is a small risk of bowel tears, bleeding, or infection after the procedure. It’s important to note this is the only colorectal prevention strategy offered.
- Virtual colonoscopy: This is the computed tomography scan of the colon. The person is asked to lie on a table of the CT scanner, which takes cross-sectional images of the colon. It is a non-invasive technique and does not require sedation. If any abnormalities are found, a colonoscopy needs to be done to remove the polyps or tumors.
- Double-contrast barium enema: A small tube is inserted in the rectum, and barium sulfate, a white chalky liquid, and air is pumped into the colon. The barium suspension lines the outer walls of the colon. X-ray images of the colon are then taken to reveal abnormalities on the inner wall of the colon. If any abnormalities are found, a colonoscopy needs to be done to remove the polyps or tumors.
- Fecal test: These are done with the fecal sample and are totally safe. Fecal tests may not give confirmatory results but may suggest abnormalities in the gastrointestinal tract, warranting further tests. A colonoscopy needs to be repeated if results are positive, indicating the presence of cancerous growth in the colon. There are three types of fecal tests:
- Fecal occult blood tests detect blood in the feces that is not visible to normal eyes through a chemical reaction.
- Fecal immunochemical tests detect blood through a specific immunochemical reaction of a protein in the blood and can detect hidden blood.
- Stool DNA tests look for certain abnormal DNA genes in the cells shed from cancerous outgrowth or polyps in the stool sample.
Who is at risk for colon cancer?
- People over 45 years of age
- People with inherited familial adenomatous polyposis, a condition where individuals develop a number of polyps in the colon and rectum
- People who had colon cancer previously
- Women with a previous history of breast, ovarian, or uterine cancer
- People whose close family members, such as parents, siblings, or children, have or had colon cancer
- People with ulcerative colitis and Crohn’s disease
- People with a sedentary lifestyle, unhealthy eating habits, and who smoke
Schedule your colon cancer screening
Colon Cancer Screening FAQs
Why are colon cancer screenings important?
Colorectal cancer typically arises from irregular growths in the colon or rectum known as polyps. During a colonoscopy exam, these premalignant polyps can be removed to help minimize the risk and possibly prevent the development of colorectal cancer. Regular colon cancer screenings may also allow doctors to identify cancer already present. It may be easier to treat colon or rectal cancer when it is detected early on.
At what age should you start colon cancer screenings?
Adults with an average risk are advised to begin regular colorectal cancer screenings upon turning 45. Those who carry a higher risk might need to screen even earlier. Your gastroenterologist can help you determine when you should start screening for colorectal cancer.
How often should you have a colon cancer screening?
The intervals at which adults should have colorectal cancer exams can depend on the type of evaluation being performed. Generally, those aged 45 and older should undergo a colonoscopy once every decade when they are at average risk of developing colorectal cancer and have normal colonoscopy results. Patients with a significantly high risk should have colonoscopy exams at least once every five years. For details on how frequently you should have screening exams for colorectal cancer, please consult your gastrointestinal specialist.
How should I prepare for my colon cancer screening?
The preparation process for a colon cancer screening will be based on the form of screening scheduled. When undergoing a colonoscopy, detailed prep instructions will be provided by your GI team ahead of the procedure to clear out your large intestine (colon). There may also be specific directions to follow in the days leading up to your exam. It is essential to comply with your physician’s directions to help ensure they can identify any concerns when performing your colorectal cancer screening.