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Date publication

janvier 2007

Auteurs

Membres identifiés du Cancéropôle Est :
Pr LEPAGE Côme


Tous les auteurs :
Lepage C, Faivre J

Résumé

The molecular genetics of CRC provides the basis for the analysis of fecal DNA. At least three different genetic pathways are involved in colorectal carcinogenesis : chromosomal instability, microsatellite instability and hypermethylation of promoters of genes. Single-target DNA assays in the absence of a universally expressed single gene mutation across all colorectal neoplasms has a too limited sensitivity. Multiple DNA alterations must be targeted to achieve a higher sensitivity. A spectrum of DNA alterations including point mutations of the K-ras, APC, p53, Bat 26 genes and long-fragment DNA have been evaluated. In the initial study based on a small number of cases, the sensitivity was found high. This result was not confirmed by a large population-based study : the sensitivity was 52% for cancer, 15% for advanced adenomas and the specificity was 94%. Economic consequences of stool DNA testing are also a source of concern. Stool-based DNA testing represents an emerging technology which cannot yet be proposed in the current scheme of CRC screening. On-going studies in large non-selected populations may help to solve unanswered questions.

Référence

Acta Endosc. 2007;37(2):231-8