Background
Colorectal cancer (CRC) is one of the most common malignant tumors and its incidence be ranked in the No.5in the all of tumor incidence. In China, the morbidity and mortality of colorectal cancer is currently ranked in the No.4and annual increment rate of4%in some large cities. Moreover CRC also is the third most common cancer diagnosed and the second leading cause of cancer death in the United States. In the global, an annual new case for colorectal cancer is1.2million cases, about20%of pati...