NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,989 terms related to cancer and medicine.
- stool guaiac test
- listen (stool GWY-ak …)
A test that checks for occult (hidden) blood in the stool. Small samples of stool are placed on special cards coated with a chemical substance called guaiac and sent to a doctor or laboratory for testing. A testing solution is put on the cards and the guaiac causes the stool sample to change color. If there is blood in the stool, the color changes very quickly. Blood in the stool may be a sign of colorectal cancer or other problems, such as polyps, ulcers, or hemorrhoids. Also called gFOBT, guaiac fecal occult blood test, and guaiac smear test.