 In 2009, Prof. Hohenberger proposed complete mesocolic excision CME as standardized, in which the same principle of TME in rectal cancer has been applied to the colon. More and more surgeons pay attention to the rationality of this surgical approach. However, the clinical application researches are still few, in particular the prospective controlled study is still none. This clinical trial will compare the CME group and non-CME group to evaluate the outcome and safety of CME for apply in clinic. 