By learning more about the most advanced screening,
diagnostics and treatment options for colorectal cancers, patients can overcome fear—the number one obstacle that prevents individuals from seeking early care.
Diagnostic procedures for colorectal cancer
Exams, tests and diagnostic procedures are used to screen for and diagnose colorectal cancer
- Digital rectal examination (DRE) — a physician or healthcare provider inserts a gloved and lubricated finger into the rectum to feel for anything unusual or abnormal. This test can detect cancers of the rectum, but not the colon.
- Fecal occult blood test — checks for hidden (occult) blood in the stool. It involves placing a very small amount of stool on a special card, which is then tested in the physician’s office or sent to a laboratory.
- Fecal immunochemical test (FIT) — A test that is similar to a fecal occult blood test, but does not require any restrictions on diet or medications prior to the test.
- Stool DNA (sDNA) — a test used to check the stool or fecal matter for specific changes in DNA (the genetic blueprint of each cell) that indicate signs of colorectal cancer. The patient is required to save an entire bowel movement and the sample is sent to a laboratory.
- Blood count — to check for anemia (a result of bleeding from a tumor).
- Sigmoidoscopy — a diagnostic procedure that allows the physician to examine the inside of a portion of the large intestine. A short, flexible, lighted tube, called a sigmoidoscope, is inserted into the intestine through the rectum. The scope blows air into the intestine to inflate it and make viewing the inside easier.
- Colonoscopy — a procedure that allows the physician to view the entire length of the large intestine. It involves inserting a colonoscope, a long, flexible, lighted tube, in through the rectum up into the colon. The colonoscope allows the physician to see the lining of the colon, remove tissue for further examination, and possibly treat some problems that are discovered.
- CT colonography (virtual colonoscopy) — a procedure that uses computerized tomography (CT) to examine the colon for polyps or masses using special technology. The images are processed by a computer to make a 3-dimensional (3-D) model of the colon. Virtual colonoscopy is non-invasive, although it requires a small tube to be inserted into the rectum to pump air into the colon.
- Double contrast barium enema — a fluid called barium (a metallic, chemical, chalky, liquid used to coat the inside of organs so that they will show up on an x-ray) is inserted into the rectum via an enema to partially fill up the colon. An x-ray of the abdomen shows strictures (narrowed areas), obstructions (blockages) and other problems.
- Biopsy — a procedure in which tissue samples are removed (with a needle or during surgery) from the body for examination under a microscope; to determine if cancer or other abnormal cells are present.