Inclusion Criteria:

- Curatively resected, histologically confirmed colon adenocarcinoma (presence of the
inferior pole of the tumor above the peritoneal reflection)

- AJCC/UICC high-risk stage II, stage III colon cancer Stage II patient with high risk
of relapse, if they fulfill one or more of the following criteria:(T4 tumors,bowel
obstruction or perforation,vascular or lymphatic or perineural invasion)

- Patients who are participating in the randomized phase II trial of FOLFOX 6 or 12
cycles

- Patients should sign a written informed consent for this translational study before
or during participating in a randomized phase III study investigating the role of
oxaliplatin duration (6 cycles versus 12 cycles) in modified FOLFOX-6 regimen as
adjuvant therapy for patients with stage II/III colon cancer

Exclusion Criteria:

- Patients who do not agree with sampling of peripheral blood for genetic analysis

- Patients who are considered not to be suitable for this study at investigator's
discretion