Colonoscopy, Our Best Defense Against Colon Cancer
Colon cancer is preventable, and also easily treatable when detected early, yet it claims approximately 50,000 lives in the United States each year. A colonoscopy is the procedure our board certified physicians perform to screen for (and when necessary, to remove) polyps, which are abnormal growths that can turn into colon cancer. Colon polyps can vary in size. Most are benign, or non-cancerous, but it’s not always possible to distinguish between a harmless polyp and a pre-cancerous polyp without a biopsy. Since cancer of the colon starts out as a polyp, removing polyps is an important means of preventing colon cancer. The incidence of polyps increases with age, and can range from 20-40 percent, depending on age and other risk factors, such as a family history of colon polyps or colon cancer.
The colonoscopy procedure is performed with a colonoscope, a thin, flexible instrument equipped with a camera and light at the tip, allowing careful examination of the lining of the colon, or large intestine. Instruments can be inserted through the endoscope to perform procedures such as taking a tissue sample, or biopsy, and to remove polyps. A colonoscopy may also be performed to diagnose the source of other symptoms, such as abdominal pain, constipation, diarrhea, and rectal bleeding.
Understanding the Colonoscopy Procedure
Colonoscopy enables us to examine the lining of your colon (large intestine) for abnormalities by inserting a flexible tube as wide as your finger into your rectum, and slowly advancing it into the colon.
What Preparation is Required?
Your doctor will tell you what dietary restrictions to follow and what cleansing routine to use. In general, the preparation consists of consuming a clear liquid diet the day before the colonoscopy, as well as a special oral laxative preparation the evening before the colonoscopy. The colon must be completely clean for the procedure to be accurate and complete, so be sure to follow our instructions carefully.
Can I Take My Current Medications?
Most medications can be continued as usual, but some medications can interfere with the preparation or the examination. Inform you doctor about medications you’re taking, particularly aspirin products, arthritis medications, anticoagulants (blood thinners), insulin or iron products. Also, be sure to mention allergies you have to medications. Alert us if you require antibiotics prior to dental procedures, because you might need antibiotics before a colonoscopy as well.
What Happens During Colonoscopy?
First, you will meet our anesthesiology team who will administer anesthesia to you during the procedure. With the anesthesia, you will be completely comfortable and should not have any recollection of the procedure.
You will lie on your left side while we slowly advance a colonoscope through your large intestine to examine the lining. We will examine the lining again as we slowly withdraw the colonoscope. The procedure itself usually takes 15 to 30 minutes, although you should plan on two hours for waiting, preparation, and recovery.
What if the Colonoscopy Shows Something Abnormal?
If we think an area needs further evaluation, we will pass an instrument through the colonoscope to obtain a biopsy. Biopsies are used to identify many conditions, and we might obtain one even if we do not suspect cancer. If colonoscopy is being performed to identify sites of bleeding, we might control the bleeding through the colonoscope by injecting medications or by coagulation (sealing off bleeding vessels with heat treatment). We might also find polyps during colonoscopy, and we will most likely remove them during the examination. These procedures don’t usually cause any pain.
What are Polyps and Why are They Removed?
Polyps are abnormal growths in the colon lining that are usually benign (noncancerous) and which vary in size. We can’t always tell a benign polyp from a malignant (cancerous) polyp by its appearance, so we will send polyps that we remove for a biopsy. Because cancer begins in polyps, removing them is an important means of preventing colon cancer.
How are Polyps Removed?
We remove polyps with wire loops called snares or with biopsy instruments. We use a technique called “snare polypectomy” to remove larger polyps. We pass a wire loop through the colonoscope and remove the polyp from the intestinal wall using an electrical current. You should feel no pain during the polypectomy.
What Happens After a Colonoscopy?
We will explain the results of the examination to you, although you will probably have to wait up to a week for the results of any biopsies performed. Someone must drive you home after the procedure. Even if you feel alert after the procedure, your judgment and reflexes could be impaired for the rest of the day. You might have some cramping or bloating because of the air introduced into the colon during the examination. This should disappear quickly when you pass gas.
You should be able to eat after the examination, but we might restrict your diet and activities.
What are the Possible Complications of Colonoscopy?
Colonoscopy and polypectomy are generally safe when performed by doctors who have been specially trained and are experienced in these procedures.
One possible complication is a perforation, or tear, through the bowel wall that could require surgery. Bleeding might occur at the site of biopsy or polypectomy, but it’s usually minor. The bleeding may stop spontaneously, but if you have significant bleeding, it is very important that you notify your gastroenterologist immediately. Additionally, some patients might have a reaction to the anesthesia used during the procedure.
Although complications after colonoscopy are uncommon, it’s important to recognize early signs of possible complications. Contact your doctor if you notice severe abdominal pain, fever and chills, or rectal bleeding of more than one-half cup. Note that bleeding can occur several days after polypectomy.
For more information about colonoscopy, visit Long Island Digestive Disease Consultants.