Fecal Occult Blood Tests (cont.)
Dennis Lee, MD
Dennis Lee, MD
Dr. Lee was born in Shanghai, China, and received his college and medical training in the United States. He is fluent in English and three Chinese dialects. He graduated with chemistry departmental honors from Harvey Mudd College. He was appointed president of AOA society at UCLA School of Medicine. He underwent internal medicine residency and gastroenterology fellowship training at Cedars Sinai Medical Center.
In this Article
How do the results of chemical fecal occult blood testing compare with immunologic fecal occult blood testing?
A chemical fecal occult blood test is inexpensive and easy, but it has several disadvantages.
The immunologic fecal occult blood test has additional advantages over the chemical fecal occult blood test. First, it is more sensitive for blood. This means that given the same amount of blood in the stool, the immunologic fecal occult blood test will more frequently be abnormal. In other words, it will more frequently detect cancers and precancerous polyps. Second, it is more specific for blood. That is, there will be fewer abnormal tests due to interfering substances in the diet, and as a result, an abnormal immunologic fecal occult blood test will more commonly be due to cancer or a precancerous polyp. As a result, less follow-up testing (for example, colonoscopy) will be necessary to pursue a falsely abnormal fecal occult blood test.