1985年,美国有138000人新患结直肠癌,并有59000人死亡.1986年有140000人发病,60000人死亡,占癌症死亡人数的首位.该病的5年生存率在近20年来一直徘徊在40～45%.该病的预后取决于肿瘤发展及转移的程度,因而早期诊断不容忽视.目前,最简便,经济的普查方法是大便潜血试验.本文报告了在宾州的Lehigh Valley对无症状志愿者进行普查的经验. In 1985, there were 138,000 newly diagnosed colorectal cancers in the United States and 59,000 deaths. In 1986, there were 140,000 disease cases and 60,000 deaths, which accounted for the largest number of cancer deaths. The 5-year survival rate of the disease has been decreasing in the past 20 years. At 40 to 45%, the prognosis of the disease depends on the degree of tumor development and metastasis, so early diagnosis cannot be ignored. Currently, the easiest and most economical census method is the fecal occult blood test. This article was reported in Lehigh Valley, Pennsylvania. Symptoms Volunteer experiences with census.