The Molecular Screening of the Stool for the Colorectal Carcinoma

Overview

Background:
Current screening methods of colorectal carcinoma are based on examination of occult bleeding in the stool, and further on endoscopic and irrigographical (barium enema) examinations. Population-based non-invasive screening method having high sensitivity and specificity is needed.

Methods:
Detection of molecular alterations in colonocytes from the stool may be a promising new diagnostic tool for such screening. Determination of mutations in APC, K-ras, DCC, p53 genes and „long“ DNA may serve for early detection of colorectal cancer from stool samples. Multi-target DNA-assays employing all these markers suggest high sensitivity and specificity, unfortunately also expensiveness. Therefore finding a marker characteristic for all tumor cells would be desirable. Nuclear faktor-kappaB (NF-κB) could be such marker suitable for determination in colonocytes shed into the stool.

Conclusion:
Molecular testing of stool for early detection of colorectal cancer may be a promising screening method for this disease. Large multicenter trials are required to validate results obtained from preliminary clinical studies.

Key words:
colorectal carcinoma – stool – screening – mutation – DNA