One expert noted that stool-based tests were never the "gold standard" for colon cancer detection, so these results are not overly surprising. In that context, "both the guaiac-based test and the immunological tests seemed reasonably sensitive in detecting cancer," said Dr. Durado Brooks, director of colorectal cancer at the American Cancer Society. "But overall, they have relatively poor sensitivity for detecting [colon] polyps."
The implications of the test results are less clear for American physicians, Brooks added, partly because only one of the six immunological tests in the study is currently available in the United States, and partly because the researchers used an older, less popular version of the guaiac test.
In addition, the German researchers used only a single sample for the guaiac-based tests, while the American Cancer Society recommends testing three samples, Brooks said.
But another expert said these types of studies are needed.
"The important point of this paper is that you must test these methods in a screening population" before widespread use, said Ann Zauber, an associate attending biostatistician at Memorial Sloan-Kettering Cancer Center in New York City.
Zauber, who is also a member of the U.S. Agency for Health Care Policy and Research's Multi-Society Task Force for Colorectal Cancer, said that "this kind of study needs to be done, and we need to assess these tests against colonoscopy."
The current American Cancer Society recommendation is that Americans over 50 at normal risk for colon cancer get a fecal occult blood test every year; sigmoidoscopy (looking at only the lower colon) once every five years; and full colonoscopy once every 10 years. One government adv
All rights reserved