大肠癌包括结肠癌和直肠癌,是常见的消化道恶性肿瘤之一,其发病率约占所有恶性肿瘤的15%[1-2]。近年来,随着人们生活水平的提高和饮食习惯的改变,我国大肠癌发病率和死亡率呈升高趋势。2012年中国肿瘤登记年报显示,我国大肠癌发病率和死亡率分别为17.29/10万和7.94/10万,分别居全部恶性肿瘤发病率和死亡率的第4位和第5位[3]。研究表明,早期大肠癌的预后较好,5年生 Colorectal cancer, including colon and rectal cancer, is one of the most common gastrointestinal malignancies and its incidence accounts for about 15% of all malignancies [1-2]. In recent years, with the improvement of people’s living standards and eating habits, the incidence and mortality of colorectal cancer in our country are on the rise. The 2012 annual report of China’s cancer registration shows that the incidence and mortality rate of colorectal cancer in China are 17.29 / lakh and 7.94 / lakh, respectively, ranking 4th and 5th of all malignant tumor incidence and mortality [3]. Research shows that the prognosis of early colorectal cancer is better, 5-year-old