Inclusion Criteria:

Surveillance of patients with a personal history of advanced adenoma or CRC:

- Informed consent obtained

- Age ≥ 18 and ≤ 80 years old

- History of advanced adenomatous polyps

- Or history of non metastatic CRC with curative surgery and without other treatment
more than 2 years before enrollment.

- Previous medical examination

Screening of patients with a Family history of CRC at high risk:

- Informed consent obtained

- Age ≥ 18 and ≤ 80 years old

- First degree family history of colorectal cancer diagnosed <60yrs during the five
previous years-Previous medical examination

Exclusion Criteria:

Personal histories

- Age < 18 or >80 years old

- history of non adenomatous polyps

- history of Metastatic CRC

- familial adenomatous polyposis, Peutz-Jeghers syndrome, hereditary non polyposis
colorectal cancer (HNPCC), juvenile polyposis syndrome

- Familial history of familial adenomatous polyposis

- Personal history of subtotal colectomy (but not of hemicolectomy, to confer to
inclusion criteria)

- Colonoscopy with a polyps resection dated more than 5 years and less than 2 years
prior to enrollment.

- Enrollment in another protocol

- no health insurance affiliation Family histories

- Age < 18 or >80 years old

- Patients with one or several family histories of first degree colorectal cancer
occured to unknown age or diagnosed after 60 years old.

- Eligible patients having already undergone colonoscopy screening

- no health insurance affiliation