New Trends in Early Detection of Colorectal Cancer

Abstract

SUMMARY
Current practice guidelines recommend annual fecal occult
blood-test screening for colorectal cancer in the averagerisk
population over the age of 50. Efficacy of fecal occult
blood-test screening is supported by several recent, controlled,
prospective trials and case-control studies.
On the other hand, a new generation of fecal tests based on
immunocytochemical and RT-PCR methods recently has
been developed.
There is strong evidence that colon screening of asymptomatic,
average-risk subjects can reduce colorectal cancer
mortality. Endoscopic screening with sigmoidoscopy can
reduce mortality associated with left-sided cancers due to
discovery of early curable cancers and the detection and
removal of premalignant adenomas. But, with this technique,
only the superficial mucosa is visua-lized and at
relatively low magnification. Thus, new imaging systems,
based on light-tissue interactions, such as optical coherence
tomography, light-induced fluorescence spectroscopy,
time-resolved fluorescence, light-scattering spectroscopy,
chromoendoscopy and magnification endoscopy are being
developed to advance endoscopic diagnosis of colorectal
cancer.