Colonoscopy & Other Colon/Rectal Screenings
With the prevalence of colon and rectal cancers in the American population (one out of 20 will develop colon or rectal cancer), screening is an invaluable tool for early detection of cancer, since unfortunately, symptoms of cancer may appear once the disease is more advanced.
With early detection, the cure for pre-cancerous polyps is about 100% and for early cancer (before symptoms start) is about 90%. In contrast, cure rates for late stage cancer (after symptoms) is only about 50%. There are several types of screening test for detecting colon cancer.
Colonoscopy, considered the gold-standard in colon cancer screenings, is a procedure that enables your physician to examine the lining of the entire colon and rectum for abnormalities (such as polyps—abnormal growths in the lining of the colon—or bowel disease) by inserting a flexible tube into the anus and advancing it slowly into the rectum and colon.
If polyps are found during the colonoscopy, they will be removed and sent for analysis to determine if they are benign (non-cancerous) or malignant (cancerous).
While colonoscopy and polypectomy (removal of polyps) are generally safe, complications can occur, although rare. Complications may include:
- Perforation or tear through bowel wall that may require surgery;
- Bleeding which is usually minor and stops on its own;
- Rarely, blood transfusions or surgery may be required.
Although complications after colonoscopy are uncommon, it is important to recognize early signs of complications including:
- Severe abdominal pain;
- Fever and chills; and/or
- Large amount of rectal bleeding.
These symptoms should be reported to your doctor.
In spite of these rare complications, colonoscopy remains the best method for colon cancer screening. Screening colonoscopy can detect and remove polyps up to ten years before cancer develops!
Routine colonoscopy should begin at age 50 or earlier if there is a family history of colorectal cancer, a personal history of inflammatory bowel disease, or other risk factors. Without any of the aforementioned risk factors, after the initial screening at age 50, colonoscopy is recommended once every ten years for early detection of colon cancer. Since polyps grow very slowly, this timeframe allows for the detection and removal of polyps before cancerous changes begin.
For people with a family history of polyps or cancer, the first colonoscopy should be done at age 40, or 10 years before the age of diagnosis of that relative. Additionally, people with a personal history of colon and rectal cancer should have a colonoscopy one year from surgery. If this first post-operative colonoscopy is negative for colon cancer or polyps, then colonoscopies can be repeated every 2-3 years. Patients who have had pre-cancerous polyps removed should have a colonoscopy every 3-5 years. However, if a polyp was found that was not completely removed, a colonoscopy would need to be repeated in 3-6 months.
Also, women with a personal history of ovarian or uterine cancer before the age of 60 should have a colonoscopy beginning at the age of 40. People with extensive inflammatory bowel disease (IBD), i.e., Crohn’s disease or ulcerative colitis should have colonoscopies at least every two years.
For people with Hereditary Non-Polyposis Colon-Rectal Cancer (HNPCC), a genetic condition with a strong family trend of colon and rectal cancer, urinary and gynecologic cancers, especially at a young age, colonoscopies should start at age 20-25, and then be repeated every 1-2 years.
Familial Adenomatous Polyposis (FAP) is a hereditary condition where colon and rectal polyps form at a very young age. The risk of cancer in these patients is extremely high. In these patients, minimally, screening should start at puberty.
If you are interested in being screened for colon cancer or polyps, call our office at (815) 717-8730 to direct-schedule your colonoscopy (without the need for a pre-screening appointment).
Our office staff will give you complete instructions to prepare you for your colonoscopy. All colonoscopy patients will need to use a bowel prep the night before this procedure because the colon must be cleaned of stool so your surgeon can clearly view the colon wall. Most patients say this is the worst part of the procedure because a colonoscopy is done under a “twilight sleep” and most patients remember nothing. The exam typically lasts about 30 minutes.
In spite of the efficacy of colonoscopy, for various reasons, patients or their physician may choose alternate screening methods for colon cancer.
Because it is the most inexpensive, non-invasive way to test, low-risk patients may undergo a fecal occult blood test. This test involves adding a chemical to a stool sample in order to detect blood in the stool. While a simple test, only polyps or cancers that are actively bleeding at the time of the test will be detected. This only happens in 10% of polyps and in 50% of cancers, so it is not considered a highly reliable test if the patient tests negative for blood in the stool. If blood is indeed detected through a fecal occult blood test, then a colonoscopy is recommended.
Flexible sigmoidoscopy is a test similar to a colonoscopy except that only the last 12-18 inches of the colon and rectum is examined using a flexible scope. Not as thorough as a colonoscopy, this test can miss up to 75% of the colon, thus missing polyps or cancers that may be located further up in the intestine. However, some patients may choose a flexible sigmoidoscopy done in conjunction with a fecal occult blood test because a flexible sigmoidoscopy is less expensive, less invasive, can typically be done in the office, and may require only limited bowel prep and dietary restrictions. It is important to note that if this testing regimen is followed, it is suggested to be performed every five years after age fifty, rather than the recommendation of every ten years after age 50 for the colonoscopy.
A barium enema or air-contrast enema, is a radiologic test that looks at the entire colon. It is less accurate than colonoscopy and is usually performed when colonoscopy cannot be done.
Virtual colonoscopy uses a CT scan to evaluate the colon. This test is usually more accurate than barium enemas, but still lacks the quality to make it a highly-effective screening tool. Traditional colonoscopy still remains the best option for thorough testing.