This study sets up the final study end point and three detailed goals as the following.

The main objective of study: This trial is done to assess the safety and benefit of early adjuvant chemotherapy from 10 to 14 days after surgery compared with conventional commencement after 2weeks for treatment of patients with colon cancer.

Detailed goal of study:

The primary endpoint: This study is designed to assess whether early commencement of adjuvant chemotherapy improves the 3-year disease-free survival, overall survival and recurrence rate.

The secondary endpoint: This study aims to compare short-term cumulative complications between early and conventional commencement of adjuvant chemotherapy after laparoscopic resection of colon cancer. This study will also assess the quality of life and side effects of chemotherapy.

Chemotherapy regimen: FOLFOX-6, every 2weeks, total 12 cycles treatment

• day1: Oxaliplatin 85mg/m2

• day1: Leucovorin 200mg/m2

• day1: 5-FU 400mg/m2 IV bolus

  • 2,400mg/m2 over 46 hours

Inclusion Criteria:

• Eligibility rule of enrollment
• Rectal adenocarcinoma that were 15 cm or more from the anal verge
• pathologically diagnosed stage II or III disease
• patients who meet the discharge criteria within 10days after surgery
• Patients with adequate hepatic, renal, and bone marrow function, and a left ventricular ejection fraction of 55% or higher measured by echocardiography

Exclusion Criteria:

• An ineligibility to participate in the clinical study based on the judgment of investigators from a legal perspective
• A past history of chemotherapy
• tumor with obstruction or perforation
• tumor with distant metastases
• synchronous tumor
• relative or absolute contraindications of chemotherapy
• Recent MI, CVA, nitrate medication
• Severe cardiovascular disease, psychiatric disease
• Severe hepatic dysfunction (GOT, GPT ≥100IU/L)
• Renal dysfunction (Cr ≥2mg/dl)
• The concurrent presence of other severe medical diseases