Over the past two decades, there have been several advancements in colon and rectal cancer treatments. However, a big part of successful treatment is detecting colorectal cancer earlier. Unfortunately, as with many other cancers, colorectal cancer doesn’t always come with obvious signs and symptoms until the cancer has progressed and sometimes even spread to other parts of the body. This is why it’s important to understand your family history and talk with your primary care physician about scheduling regular colorectal cancer screening. 

Even if you’re feeling fine, we at Rocky Mountain Cancer Centers (RMCC) recommend that you follow the guidelines set in place by the American Cancer Society, which is to be screened starting at age 45. 

Fortunately, there are several screening tests for colon and rectal cancers, including some that were recently made widely available. In addition to detecting colorectal cancer when it is present, regular screening can also prevent it by allowing your doctor to find and remove polyps before they have a chance to turn into cancer. To stay on top of your health, we recommend you take time to schedule an appointment with your primary care physician so you can learn more about your colon cancer screening options. 

Common Types of Screening for Colon and Rectal Cancers

When it comes to screening, you have six main options to choose from. These tests range from those that are performed at a healthcare facility to those that can be conducted at home. Keep in mind that even though at-home testing offers more privacy, they can often lead to a false positive or a misinterpretation of the results. 

In general, the best method of screening depends on factors such as your age and risk for developing colon and rectal cancer. Talking with your doctor can help when it comes to making a decision on a screening test. 


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At-Home Testing for Colorectal Cancer

If you're under 50, your doctor may suggest at-home testing before a colonoscopy or other test performed by a healthcare professional. This allows you to do the test in the comfort of your home without a day of colon preparation before a colonoscopy. It's important to note, however, that these tests can miss many polyps and some cancers. 

Stool DNA Test

If you’d like to avoid the preparation and invasive testing of a colonoscopy, you can request a stool DNA test. Once you have the take-home test kit provided by your doctor, you will collect a stool sample and mail it to a lab. The test checks for blood in the stool and gene changes.

Although stool DNA tests are convenient and non-invasive, they are not for everyone. This type of testing should be reserved for only those with an average risk for colon or rectal cancer. If the test results are abnormal, additional testing through colonoscopy may be needed. 

Guaiac-based Fecal Occult Blood Test (gFBOT)

Another test that can be picked up from your doctor and taken home is the guaiac-based fecal occult blood test (gFBOT). After you collect a stool sample onto a test card, you will return the card back to the doctor’s office for testing. Because tiny amounts of blood can go unseen by the naked eye, high-sensitivity blood tests, such as the gFBOT, can be an incredibly valuable screening tool. 

gFBOT uses a chemical to detect heme, a component of the blood protein hemoglobin. Since this test may detect heme in certain foods and medications, such as red meat, you will most likely be required to eat a special diet prior to screening.

Fecal Immunochemical Test  (FIT)

A fecal immunochemical test (FIT) is very similar to the gFBOT, and it uses antibodies to specifically detect human hemoglobin protein. However, unlike the gFBOT, there are no dietary restrictions prior to testing.

Colorectal Cancer Screening Performed at a Healthcare Facility

We understand that taking time out of your day to visit the doctor for screening can seem like a nuisance. And there's the "prep time" when you need to clean your colon for the doctor to see inside clearly.

But these are the most accurate and helpful of the colorectal cancer screenings and can allow the doctor to remove any polyps that may be suspicious. Your doctor will talk with you about which one of the following on-site tests is the best one for you:

Standard Colonoscopy

During a standard colonoscopy, a flexible lighted tube called a colonoscope is used. Inserted into the rectum, the colonoscope features a lens for viewing and a tool for removing tissue. Air is inserted into the rectum, helping doctors to better view the colon lining. If any abnormal growths are identified, they can be removed for testing during this procedure. 

A thorough cleansing of your colon prior to testing as well as being sedated during the test are two important steps that help contribute to a successful colonoscopy. According to the National Cancer Institute, studies show that colonoscopy screening can reduce colorectal cancer deaths as much as 60-70%. Because of this, colonoscopy is often the preferred screening test for early detection. A key benefit of a colonoscopy is the ability to view the entire colon. 

Virtual Colonoscopy 

With a virtual colonoscopy (or CT colonography) test, a CT scanner takes images of your colon. This test typically does not require sedation, however, it does require bowel preparation. During the test, air is pumped into your colon and rectum, which makes it possible for the scanner to show detailed, cross-sectional images. If the doctor sees polyps or possible cancer, a standard colonoscopy may be ordered for confirmation.  

If you are at average risk for colon cancer and are age 50 and older, then you are an ideal candidate for a virtual colonoscopy. A doctor may also order a virtual colonoscopy if there is a bowel obstruction or you are at risk for complications from a regular colonoscopy. 

Flexible Sigmoidoscopy

Similar to a colonoscopy; however, this test looks only at part of your lower colon and rectum using a thin lighted tube-like instrument. In most cases, there is no need for sedation during a flexible sigmoidoscopy test. Doctors can either remove polyps during the test or order a colonoscopy. Although bowel preparation is necessary, it is not as extensive as that required for a colonoscopy. 

When to Get Screened for Colorectal Cancer

Recently, the American Cancer Society (ACS) lowered the recommended screening age from 50 to 45 for colon and rectal cancer. This new recommended age resulted from research that found increasing cases of this type of cancer among younger adults. Research remains ongoing, however, several contributing factors attributed to the increase are poor diets, lack of physical activity, and obesity. 

In general, screening recommendations for colon and rectal cancer differ based upon whether you are at average risk or high risk for the disease. Patients who are at average risk tend to have no family history of colorectal cancer and are, on average, fairly healthy. The ACS recommends average-risk patients undergo a thorough screening every ten years.

If you are considered at high risk for colorectal cancer it is likely that you have one or more of the contributing factors:

  • A family history of colon or rectal cancer
  • Problems with inflammatory disease 
  • Radiation to the pelvic area from a previous cancer

If you fall into the high-risk category, the ACS recommends beginning screening earlier than age 45 and scheduling screenings more frequently than every 10 years. Prevention is key and especially important for those at high risk of developing colon or rectal cancer.  

When Test Results Come Back Abnormal 

Before a doctor can diagnose colon or rectal cancer, further testing is often required. When any test other than a colonoscopy indicates abnormalities, a doctor may order a colonoscopy in order to view the colon in its entirety.

If pathology testing of polyps removed during a colonoscopy returns a cancer diagnosis, your doctor will work to stage the cancer. Discovering whether the cancer has spread helps a doctor to determine the stage. 

It is important to remember that not all polyps are cancer. Before jumping to conclusions, wait to hear from your doctor.  Download our free guide for newly diagnosed colorectal cancer patients.

Rocky Mountain Cancer Centers is Here to Help

If cancer treatment is needed, RMCC is here to help. Our colorectal cancer specialists throughout Colorado are available for an appointment at a location near you. 

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