What is colon cancer?
Colorectal cancer (also referred to as colon cancer) is cancer that develops in the colon (large intestine) or the rectum. Colorectal cancer usually develops slowly over a period of many years. Before cancer develops, it usually begins as a non-cancerous growth often referred to as a polyp. A polyp is an abnormal growth of tissue lining the colon or rectum. One specific type of polyp, called an adenoma, has the greatest risk of becoming cancer.
Why should I be checked?
Colorectal cancer is the third most commonly diagnosed cancer and the second leading cause of cancer related death among males and females in the United States. It is estimated that approximately 1 in 20 Americans, both men and women, will develop colon cancer.
- Due to early detection of polyps, the death rate from colorectal cancer has been decreasing for the past 15 years. When colon cancer is diagnosed earlier, it is easier to cure, but only 39% of colorectal cancers are found at an early stage. There are approximately one million survivors of colorectal cancer in the United States.
- 90% of those diagnosed in the early stages are still alive five years following their diagnosis. However, once colorectal cancer has spread to nearby organs or lymph nodes, the likelihood of remaining alive five years after diagnosis significantly decreases.
In many cases, regular screening can prevent colorectal cancer by finding and removing pre-cancerous polyps before they become cancerous.
When should I be screened for colon cancer?
There are no strict guidelines on when colon cancer screening should begin. However, all average-risk individuals should be screened no later than the age of 50. The American Cancer Society recommends commencing screening for average-risk individuals at age 45.
Those with a family history of colorectal cancer should start the screening by age 40 or ten years before the index case (for example, if the father has cancer at age 46, screening should begin at 36 for all children). Some guidelines recommend African-Americans should be screened by age 45, as colon cancer tends to strike this sector of the population at an earlier age.
What symptoms does colon cancer cause?
Your doctor will likely order a colonoscopy or other screening tests for colon cancer if you are 50 years or older, even if you have no symptoms, because pre-cancerous polyps and even early colon cancer often cause no symptoms.
However, if symptoms are present, they may include:
- Diarrhea or constipation
- Nausea or vomiting
- The feeling that your bowel does not empty completely
- Finding blood (either bright red or very dark) in your stool
- Finding that your stools are narrower than usual
- Frequently having gas pains, cramps, or feeling bloated
- Losing weight with no known reason
- Feeling very tired all the time
These symptoms can also be associated with many other health conditions. If you have any of these symptoms, discuss them with your doctor. Only your doctor can determine why you’re having these symptoms. Usually, cancer does not cause pain in its early stages; however, you should not wait until you begin to feel pain to check with your doctor.
Are there any screenings available?
There are a number of ways to examine the colon and each method has its advantages and disadvantages. In the past, X-rays were combined with a special dye inserted through the anus (Barium Enema) as the standard test to look for abnormalities inside the colon. This method is still sometimes used, usually when a complete colonoscopy is not possible, but has largely been replaced by direct examination of the colon via colonoscopy.
A colonoscopy is the only screening method that provides a precise diagnosis by taking a biopsy and reducing the risk of colon cancer by removing polyps. Other tests such as a virtual colonoscopy, or a CT colonography, a type of CT-scan, are being evaluated for select situations. This test has been shown to miss smaller sized polyps than a standard colonoscopy, and experts have not come to a conclusion on its use for routine screenings. Abnormal results often still require further clarification using a standard colonoscopy.
What are the differences between at-home colon cancer screening tests and a colonoscopy?
At-home colon cancer screening tests (Cologuard and FIT testing) are decent at detecting colon cancer but not good for detecting polyps, the precursors to colon cancer. If you have a positive at-home colon cancer screening test, you need a colonoscopy to investigate why it is positive. False positives do occur. Colonoscopy is an outpatient colon cancer screening procedure that is good for detecting both colon cancer and polyps. Furthermore, during your colonoscopy your gastroenterologist will remove any polyps that are found, so that the polyps never have a chance to become a colon cancer. By detecting and removing polyps, colonoscopies can significantly reduce your risk of developing colon cancer.
In short, colonoscopies are the gold standard for colorectal cancer screenings and the preferred method because of its ability to detect potential colorectal cancer early.
If you have a history of polyps or a family history of colon cancer, which type of colon cancer screening is recommended?
If you have one of these histories, you are considered to be in a high risk group for colon cancer, and because you want to use the best test for detecting polyps, colonoscopy is the ONLY form of colon cancer screening that is recommended.
What should I expect with a colonoscopy?
Colonoscopies are an outpatient procedure performed under sedation in which a tube with a light and camera are used to examine the lining of the colon. In preparation, your doctor will ask you to undergo a cleansing process allowing them to clearly and accurately examine the colon. The goal of a colonoscopy is to evaluate the colon for signs of cancer or pre-cancerous growths (polyps). If pre-cancerous growths are detected or suspected during the procedure, your doctor will remove them at that time, and have them sent for testing.
What preparation is required?
Your doctor will tell you what sort of diet and cleansing routine to follow before the test. In general, the “prep” involves drinking a special cleansing solution, like Miralax, along with plenty of clear fluids, such as water and lemon-lime Gatorade, as well as taking special laxatives by mouth. Be sure to tell your doctor about conditions such as diabetes, heart and/or kidney disease, or if you are taking any blood-thinning medications. You should plan your prep diet ahead of time and check with your doctor if you have any questions.
Is a colonoscopy painful?
A colonoscopy is a very comfortable exam because it is usually done with intravenous sedation. This means that you’ll be in a very sleepy state during the procedure. Most patients are not even aware that the procedure happened when they wake up.
How long does a colonoscopy take?
On average, the procedure takes about 20 to 30 minutes to perform. However, you will likely need to be at the facility for 2 to 3 hours to allow for pre-procedure and recovery time.
What happens after a colonoscopy?
Your physician will explain the results of the examination, but you will probably have to wait for the results of any biopsies. If you received sedation during the exam, you will need to have a friend or relative take you home. Even if you feel alert after the procedure, your judgment and reflexes could be impaired for the rest of the day.
You might experience some cramping or bloating because the doctor uses air to inflate the colon when looking at the lining, but this feeling should disappear once you start passing gas. Although you should be able to eat shortly after the examination, your doctor might restrict your diet and activities if a procedure, such as removing a polyp, was performed.
What are the possible complications or risks of a colonoscopy?
Colonoscopies and the special techniques mentioned above are very safe when performed by specially trained doctors with experience in these types of procedures. As with any medical procedure, there is a risk of complications that you should be aware of.
There is a small possibility of having a reaction to any of the drugs given during the exam. In most cases, medications are available to counteract these side effects. A rare complication is the tearing or perforation of the lining of the intestine. Should this occur, surgery may be needed to seal the injury. Another risk is bleeding, usually at the site of a biopsy or polyp removal. Most cases of bleeding stop without treatment or can be controlled at the time of the procedure.
Will insurance pay for colon cancer screening?
Typically, insurance will pay for one colon cancer screening test. That is, they will cover either an at-home colon cancer screening test or colonoscopy. Not both. If you have a positive at-home colon cancer screening test, you will have to pay for the required follow-up colonoscopy out-of-pocket.