There are four basic tests for colon cancer: a stool test (to check for blood); a barium enema (x-ray) test; sigmoidoscopy (inspection of the lower colon); and colonoscopy (inspection of the entire colon). All four can detect cancers in the early stages, when treatment is most beneficial, but colonoscopy is the most accurate. A newer text, CT colonogrpahy ("virtual colonoscopy"), uses CT scanning to evaluate the colon, but it requires the same through bowel cleansing as colonoscopy.
Review Date: 5/18/2012
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.