The natural history of colorectal cancer. Opportunities for intervention

摘要: There is now a better understanding of the natural history colorectal cancer, which has provided basis for intervention to influence outcome. The possible interventions include earlier detection removal premalignant adenomas, demonstration mucosal field defect that precedes neoplasia evaluate baseline risk and its change with dietary modification, identification inherited factors. Five controlled trials evaluating early cancer fecal occult blood testing have enrolled more than 309,000 patients. Early stage cancers improved survival been observed, but data on mortality reduction not as yet reported. Studies patients adenomas demonstrated high synchronous metachronous rates complete colon evaluation initially surveillance follow-up program. Hyperproliferation lack normal differentiation observed in preceding neoplasia. Inherited factors recently shown be important larger proportion individuals destined develop cancer. These observations new opportunities application radiologic endoscopic techniques diagnosis surveillance; each examination merit. Further research needed answer many critical questions raised regarding impact these interventions.