Diagnosing Colorectal Cancer

Digital rectal examination (DRE): a physician or healthcare provider inserts a gloved finger into the rectum to feel for anything unusual or abnormal.

Fecal occult blood test: patients place a very small amount of stool on a special card, which is then tested in the physician's office or sent to a laboratory for hidden blood (occult).

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.

Sigmoidoscopy: a diagnostic procedure that allows the physician to examine the inside of a portion of the large intestine, and is helpful in identifying the causes of diarrhea, abdominal pain, constipation, abnormal growths and bleeding. 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, and can often help identify abnormal growths, inflamed tissue, ulcers and bleeding. 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.

Barium enema with air contrast (also called a double contrast barium enema): 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 given into the rectum to partially fill up the colon. An x-ray of the abdomen shows strictures (narrowed areas), obstructions (blockages) and other problems.