The main objective of this study is to identify and characterize subpopulations of cells with invasive capacity in colorectal cancer from primary tumor, blood and metastatic samples.

Secondary objectives include:

• Determine the intrinsic properties essential for the dissemination and chemoresistance of these cells capable of initiating tumors
• Identify a "molecular signature" for potential invasiveness and chemoresistance of cells initiating metastases.
• Describe the evolution of patients during 24 months of follow up and correlations with observed cellular profiles.
• Enrich the tumor bank of the institution.

Inclusion Criteria:

• The patient must have given his/her informed and signed consent
• The patient must be insured or beneficiary of a health insurance plan
• Patient with adenocarcinoma-type colorectal cancer:
• stage III at diagnosis, surgical resection of the primary tumor proposed.
• stage IV at diagnosis, surgical resection of the primary tumor and possibly of metastases proposed.
• Stage IV who have already undergone surgical excision of the primary tumor, and for whom metastasectomy is now proposed.

Exclusion Criteria:

• The patient is participating in another study
• The patient is in an exclusion period determined by a previous study
• The patient is under judicial protection, under tutorship or curatorship
• The patient refuses to sign the consent
• It is impossible to correctly inform the patient
• Patients for whom surgical resection of the primary tumor is not considered as an option
• PStage IV at diagnosis, but metastasectomy is not considered as an option
• Patients with positive HIV, Hepatitis B or Hepatitis C serology

Patients with operable, stage III or IV, adenocarcino-type colorectal cancer treated at the Nîmes University Hospital.