Colorectal cancer is the third leading cause of cancer death for both men and women in the United States. Screening colonoscopy is the gold standard to reduce incidence of late-stage cancer diagnosis by removing precancerous polyps.
Despite this, we estimate that only 66% of our population are participating in a screening program. More recently, we have noted an increasing trend in new cases in adults younger than 50 and this has led to a new recommendation from the U.S. Preventive Services Task Force (USPSTF) to advocate for screening average risk adults at the age of 45.
Many people with colorectal cancer experience no symptoms in the early stages of the disease, which is why it’s so important to get regular screening tests. Screening tests can find precancerous abnormal growths in the colon or rectum that can be removed before they turn into cancer - essentially preventing the disease.
The new recommendations from the USPSTF applies to asymptomatic adults aged 45 or older who are considered average risk for colorectal cancer (no prior diagnosis of colorectal cancer, adenomatous polyps, inflammatory bowel disease, family history in a first degree relative with colorectal cancer).
There are a variety of different screening tests for colorectal cancer:
- Stool Tests: These tests look at the stool for possible signs of abnormal growths called polyps. They are typically performed at home, so it is the most convenient compared to other tests. However, stool-based tests are required to be done yearly and if the results are positive (abnormal), you will need to proceed with a colonoscopy. These tests should be utilized in asymptomatic and average risk adults.
- Flexible Sigmoidoscopy: For this screening, the doctor uses a flexible, narrow tube with a tiny camera on one end and inserts it into the rectum to check for swollen or irritated tissue, polyps and cancer inside the rectum and lower third of the colon. A sigmoidoscopy is recommended every five years.
- Colonoscopy: Colonoscopies are considered the gold standard of colorectal cancer screenings. This test is similar to flexible sigmoidoscopy, except the doctor uses a longer tube and inserts it into the entire colon and inside the rectum. The doctor also is able to find and remove most polyps and some cancers during the screening. If anything unusual is found during the other screening tests, a colonoscopy can be used as a follow-up test. If nothing abnormal is found, a colonoscopy isn’t required for the next 10 years.
- CT Colonography: A computed tomography (CT) colonography, also called a virtual colonoscopy, uses X-rays and computers to produce images of the entire colon, which are then displayed on a computer screen for the doctor to detect changes or abnormalities in the colon and rectum. In order to produce the images, a catheter, or a small tube, is placed inside the rectum and fills your colon with air or carbon dioxide.
What is the Right Screening Test for Me?
Each screening test has its advantages and disadvantages, but the best test is the one that gets done. While there are standard recommendations for screenings it’s important you talk to your doctor about your risk factors. Certain factors like a family history of colorectal cancer or certain ethnicities may have increased risk, which means you may need to be screened more frequently or earlier than the standard recommendations.
For patients with confirmed or suspected colorectal cancer, the MemorialCare Cancer Institutes offer a collaborative approach to diagnosis and treatment, including the latest in targeted treatments, radiation therapy and surgery.
Learn more about the author, Dr. Aranez.