Exploratory Study of the Relevance of a Blood Test in the Management of Patients in the Context of Colorectal Cancer Screening

"In cohort A: Blood sample n°1 (PBMC, plasma, ctDNA) previous colonoscopy. If no cancer lesions: STOP. If cancer lesion detected : Blood sample n°2 (PBMC, plasma, ctDNA) collected 1 month after surgery.~In cohort B: Blood sample n°1 (PBMC, plasma, ctDNA) collected before surgery. Blood sample n°2 (PBMC, plasma, ctDNA) collected 1 month after surgery"

In each cohort, tumor tissue will be collected from the surgical specimen.

In cohort B: Stool sample n°1 collected before surgery. Stool sample n°2 collected 1 month after surgery