The primary aim of this study is

- to determine the difference of survival outcome (3-year overall survival, 3y OS) between after minilaparotomy and after laparoscopy..

Other aims include to determine the data below when minilaparotomy and laparoscopy are compared with each other.

• 3-year disease free survival, 3y DFS
• 5-year overall survival, 5y OS
• 5-year disease free survival, 5y DFS
• Local recurrence rate, LRR
• Postoperative complications Incidence and mortality at 30 days

Inclusion Criteria:

• Colorectal cancer with pathological results.
• Colorectal cancer preliminary diagnosed during colonoscopy.
• No confirmed metastasis.
• No comorbidity of other malignancy.
• The primary tumor is less than 10 cm.
• No organ dysfunction.
• The patient and his families totally agree with the whole investigative procedure, and sign the written informed consent form.

Exclusion Criteria:

• Diagnosed with any other malignancy within 5 years.
• Comorbidity of emergent conditions like perforation.
• Former colorectal surgery history which may affects digestive tract reconstruction.
• Need combined organ resection.
• ASA grade IV or V.
• Pregnant or lactating Women.
• Severe mental diseases.
• Severe cardiopulmonary diseases which reduce operation tolerance.
• Systematic steroid therapy lasting for more than 1 month.
• Intolerant of laparoscopy.
• No written informed consent form signed.