大肠癌是指原发于大肠黏膜上皮的恶性肿瘤,是结肠癌与直肠癌的总称,为消化道常见的恶性肿瘤,其发病率仅次于胃癌与食管癌。据有关资料表明,目前大肠癌的发病率呈逐年上升的趋势。在欧美经济发达国家,居内脏恶性肿瘤的第一、二位。在我国,其发病率与死亡率约占常见恶性肿瘤的第 Colorectal cancer refers to the primary malignant tumor in the large intestine mucosa, colon and rectal cancer is the general term for the common malignant tumor of the digestive tract, its incidence is second only to gastric cancer and esophageal cancer. According to the data shows that the current incidence of colorectal cancer showed a trend of rising year by year. In Europe and the United States economically developed countries, ranking the first and second visceral malignant tumors. In our country, its morbidity and mortality account for about the common malignant tumors