Susceptible population of colorectal cancer, in order to be able to detect colorectal cancer in the precancerous lesions and early cancer, has been widely at home and abroad to carry out the work of colorectal cancer screening. In order to achieve greater efficiency screening, the domestic and international research, that the screening of risk patients should first be graded according to their personal and family history of the screening were divided into:
(A) general risk populations
Is asymptomatic, no risk factors for colorectal cancer the natural population. Due to colorectal cancer incidence both men and women, are increasing with increasing age. The older, the higher the incidence of colorectal cancer over 60 years old increased more apparent. National census data suggest: a high incidence of colorectal cancer aged 50-79 years. The efficiency of the census / bid analysis, that the risk of the general population census to determine the age of 50 years of age is appropriate.
(B) moderate-risk populations
No symptoms, but adenomatous polyps or cancer, including the uterus or a history of colorectal cancer, their risk of colorectal cancer risk is higher. These people at high risk screening should be more active, earlier start, the implementation of more frequent or more intensive use of more sensitive methods.
Susceptible of colorectal cancer (c) high-risk populations
A personal history of inflammatory bowel disease or familial adenomatous polyposis, hereditary non-polyposis colorectal cancer family history were classified as high risk populations. Inflammatory bowel disease patients may think that, in its duration and scope of the bowel disease, the same risk of colorectal cancer may be. Research data show that: high-risk groups of colorectal cancer incidence of colorectal cancer than the general population at risk of high 2_6 times. Who have a family history of colorectal cancer relative risk of colorectal cancer occurrence in general population 1.8_8 dangerous times. The risk of colorectal cancer as the number of relatives increases, a relative risk of colorectal cancer, the risk of colorectal cancer is 1.8 times the general population at risk; with two or more relatives with colorectal cancer, its risk 5.7 times. Degree relatives of colorectal cancer before the age of 55, his own probability of occurrence of colorectal cancer is 1.7 times the general population at risk, relatives of colorectal cancer have 45_55-year-old who, the individual risk of colorectal cancer risk for the general population 3 times , 45 relatives of colorectal cancer before the age of those occurred in the individual risk of colorectal cancer is 5 times the general population at risk.
Another statistics, family history of colorectal cancer incidence is also related to age-related. Strictly speaking, many risk factors, such as I who have had colorectal cancer or colorectal adenoma, my long-term risk of ulcerative colitis, I had female genital tumors, particularly received pelvic radiation therapy should be monitored are the object of follow-up instead should be census.