Presence of Circulating Tumor DNA in Colorectal Cancer

Cancer is a DNA disease characterized by the presence of genetics alterations in cancer cells.
The recent studies underline that these recurring alterations must be considered as a good molecular marker. In fact, they could use for tumor DNA detection in different biological fluids.
So, the main purpose is to define the presence of circulating tumor DNA in the patients plasma with colorectal cancer, by the presence of mutation (KRAS, NRAS, BRAF, APC, TP53 and MIRCOSATELLIE instability).
These molecular analysis will be done both in tumor and plasma samples,
This trial allows to characterize the prognostic value of circulating tumoral DNA presence in colorectal cancer.