结直肠癌在全球癌谱中的地位逐渐上升。据联合国欧洲消化病联合会统计,2000年结直肠癌在欧洲癌谱中高居第三位;而我国2000年结直肠癌发病率也仅次于肺癌位居第二[1]。研究已表明,结直肠癌是结直肠上皮细胞受遗传和环境等多种因素作用导致基因畸变的结果。迄今,结直肠癌的确切发 Colorectal cancer in the global cancer spectrum status gradually increased. According to the UN’s European Union for the Analysis of Digestive Disease, colorectal cancer ranked the third highest in Europe in 2000, while the incidence of colorectal cancer in 2000 was second only to that of lung cancer in China [1]. Studies have shown that colorectal cancer is a colorectal epithelial cells caused by genetic and environmental factors such as the result of gene aberrations. So far, the exact incidence of colorectal cancer