Laparoscopic surgery has been widely accepted for its minimal invasion and safety. However, whether it has the same survival benefit as the traditional open surgery in Chinese population is still unknown. So we designed this study to evaluate the 3 year disease free survival rate in the laparoscopic group versus the open surgery group.

Inclusion Criteria:

• Informed consent
• Pathologically confirmed adenocarcinoma
• Pre-surgery image staging as (CT/MRI):T2-3,N0-2,M0,(TNM stage，AJCC，version of 2003)
• Single tumor locating at cecum, ascending colon, descending colon, sigmoid colon, rectosigmoid junction, rectum(distance from anal verge more than 7cm)
• Tumor diameter less than 6cm
• Age 18-75 year
• ECOG 0-2
• Predicted survival longer than 6 months
• Normal liver, renal, bone marrow function: (GPT less than 2 ULN，total bilirubin less than 1.5mg/dl，Cr less than 1.5 ULN，WBC more than 4×109/L，PLT more than 100×109/L)
• No previous history of gastrointestinal surgery
• No previous history of chemotherapy or radiotherapy

Exclusion criteria

• Severe and uncontrolled medical disease including unstable angina pectoris, cardiac infarction and cerebral attack in 6 months
• Could not tolerant general anesthesia or surgery for other organ dis-function
• Allergy to chemotherapeutical agents in the protocol
• History of other malignant tumor within 5 years
• Severe mental disorder
• Continued systematic steroid therapy
• Woman during pregnancy or lactation
• Under study of other clinical trial
• No compliance of the protocol
• Discovery of distant metastasis during surgery
• Postsurgery stage of I or IV tumors