Screening Tests for Colorectal Cancer

Understanding different types of screening tests for colorectal cancer

Michael Weisberg MD, an experienced Plano gastroenterologist, believes patients benefit from understanding the different types of screening tests for colorectal cancer. Colorectal cancer occurs in the colon (the large intestine), the rectum or both areas. This cancer is usually slow-growing, so early detection and treatment save lives.

Screening tests for colorectal cancer are based on individual needs

Patients can discuss the various screening tests for colorectal cancer with Dr. Weisberg to help decide which one is right for them. Here are some of the factors that our Plano gastroenterologist will take into account:

  • The patient’s age, health, personal and family medical history
  • The patient’s preference
  • Concerns about the test, including test prep, sedation, follow-up care and convenience
  • The cost and insurance coverage available

Types of screening tests for colorectal cancer

Colonoscopies and sigmoidoscopies are types of screening tests for colorectal cancer that allow our physician to directly view the colon and rectum.

Colonoscopies are the gold standard to look for polyps, which are the growths that can turn into cancer and colorectal cancer. Patients receive sedation for this test before the physician inserts a flexible, lighted tube into the anus and through the rectum to view the entire colon. The tube holds a camera that allows our Plano gastroenterologist to view the colon on a large television screen. It also has a working channel through which he can pass instruments to remove polyps or take biopsies of growths in the colon during the procedure.

Flexible sigmoidoscopy is another screening test for colorectal cancer that is similar to the colonoscopy, but it only allows the physician to view the sigmoid, or lower, colon. Carbon dioxide is pumped into the colon to expand it and provide a better view. A sigmoidoscopy requires less preparation than a colonoscopy and usually does not require sedation. Because it does not provide a complete view of the colon, Dr. Weisberg does not feel this is an adequate screening test for colorectal cancer.

Fecal occult blood tests and stool tests are screening tests for colorectal cancer that patients can do at home every year or two. However, they are not as effective as colonoscopies for cancer detection.

High-sensitivity fecal occult blood tests (FOBT) detect small amounts of blood in the stool that may indicate cancer or another problem. These tests include the Guaiac FOBT and the FIT test. If these test results are positive, then a colonoscopy must be performed. Many primary care doctors will use these tests to screen their patients, then refer their patients with positive test results to Dr. Weisberg for a colonoscopy.

Cologuard® is a stool test that has recently come out on the market that not only detects small amounts of blood in the stool, but also identifies nine DNA biomarkers that occur in three genes found in colorectal cancer. Dr. Weisberg only utilizes this test for patients he thinks are at high risk for undergoing colonoscopy due to advanced age or other medical conditions. However, patients need to understand that a positive Cologuard® test must be followed up with a colonoscopy to determine whether colon cancer is present.

Dr. Weisberg is a highly trained and experienced gastroenterologist that provides screening tests for colorectal cancer. To learn more, contact our Plano gastroenterologist.