结肠癌和直肠癌在国外某些地区如北美、澳大利亚、新西兰及西欧大部分地区发病率较高;美国结肠及直肠癌占主要癌瘤之第二位,仅次于皮肤癌,每年新发现病人超过10万人,每年有5万多人死于此病。国内除血吸虫病流行区外,一般均偏低。宁夏回族自治区肿瘤流行病学调查组材料统计:1974—1976三年平均死亡专率,结肠癌为1.31/10万,直肠癌为1.49/10万。主要恶性肿瘤死亡中,直肠癌占1.97％,为第七位;结肠癌占1.73％为第八 Colorectal cancer and rectal cancer are higher in some parts of the world such as North America, Australia, New Zealand and most parts of Western Europe; the United States is the second most common cancer in colon and rectal cancer, second only to skin cancer, and patients are newly discovered each year. More than 100,000 people, more than 50,000 people die every year. In addition to the endemic areas of schistosomiasis in China, they are generally low. Ningxia Hui Autonomous Region Tumor Epidemiology Research Group Material Statistics: 1974-1976 three-year average mortality rate, colon cancer was 1.31/100, and rectal cancer was 1.49/lakh. Among the major malignant tumors, rectal cancer accounted for 1.97%, which was the seventh; colon cancer accounted for 1.73% was the eighth