BANGOR, Maine (WABI) - One of the hardest parts of my job is sitting with a patient who is presenting to the emergency room with abdominal pain or bowel blockage and telling them that their workup shows a colon cancer that has already spread too far for us to be able to help. Telling anyone about any cancer is giving devastating news, however, colon cancer stings a bit more because we know enough now to detect it early, while it's still possible to eradicate and completely cure. The best test to detect an early colon cancer is a colonoscopy which can also be used to diagnose a variety of other conditions. A colonoscopy is an exam of the lower part of the gastrointestinal tract or what we call the colon. It is a safe procedure that takes between 20 and 60 minutes and is performed by inserting a device called a colonoscope into the anus and advancing it through the entire colon. Your doctor may recommend a colonoscopy for a myriad of reasons: as screening for polyps after the age of 50, rectal bleeding or dark stools, a change in bowel habits, anemia from iron deficiency which indicates blood loss, a family or personal history of colon polyps or cancer, and abnormal imaging studies such as CT scan.
A lot of patients have many worries about undergoing a colonoscopy and fear that it will be unpleasant and traumatic. The truth is that it is done under sedation and typically involves minimal discomfort. It does require some preparation, more specifically a complete cleaning of the colon to be able to detect any abnormalities. Your doctor's office will usually provide specific instructions about how to achieve that: it will require drinking a preparation a day prior to your procedure that acts as a strong laxative and causes you to have diarrhea. The preparation may not be very tasty so it is advisable to add sugar-free flavored packets to it to make it easier to drink. It is important to drink clear liquids like water, clear broth, coffee, and tea up to several hours before the procedure. You should be able to continue taking your medications right up to the day of the procedure unless your doctor specifies otherwise. Ask about any medication that increases the risk of bleeding such as Coumadin or Plavix, as you may need to have a polyp removed or biopsied. Before the procedure your doctor will obtain a signed consent from you. Then you will be taken to the procedure room and given sedation which may or may not cause you to sleep. The doctor will then insert the colonoscope and gently inflate air into the colon as they try to navigate it and visualize all its parts. You will likely pass gas so try not to be embarrassed about it as this is simply the insufflated air making its way out. After the colonoscopy you will be observed for a short while in the recovery room and your doctor will discuss the findings with you although final biopsy results will take a few days to come back. You should plan to have a ride home as you will not be able to drive as the sedation wears off and you may have some cramps. Most of the time, you will be able to eat a regular diet right after. Although generally safe, complications, however rare, may occur and they include bleeding from biopsy sites, tears in the colon, complications from the sedatives or missing an important finding. If you experience severe pain, a firm abdomen, bleeding from the rectum, vomiting or fever, you should contact your doctor immediately. Colonoscopies are often the best but they are not the only modality to screen for colon cancer.
Other tests include:
• Sigmoidoscopy, a similar procedure that examines only the last part of the colon
• CT colonography also known as virtual colonoscopy which uses a CT scan to find polyps.
• Stool test for blood which can result in a lot of false positives
• Stool DNA test which tests for genetic markers of cancer
Your doctor may have a specific reason to use one of those tests instead of a colonoscopy to look for polyps. The most important thing is to be screened somehow as colon cancer can be a curable condition if diagnosed early and acted on precipitously.