ANTIOXIDANTS IN CHEMOPREVENTION OF COLORECTAL NEOPLASMS

结肠癌与可识别的地理位置的关系 地点，更具体地说，与某些饮食习惯，导致了 推测饮食因素调控可能有助于降低 这种疾病的发病率。 抗氧化剂已被证明可以减少 实验模型中化学诱发癌症的发病率， 的胃液和尿液中的致癌物质水平 某些人类群体。 随着粪便诱变剂的鉴定， 结肠癌高危人群中， 这些诱变剂水平的降低可能会降低结肠癌的发病率， 癌 两种无毒补充的实际效果 抗氧化剂，抗坏血酸和α-生育酚，对这些水平 各种人体组织和排泄物中的化合物没有明确定义。 我们计划测量组织中抗坏血酸水平的变化， 不同水平膳食补充剂对正常人α-生育酚的影响 患者 然后，我们计划确定一个人口的个人与粪便 诱变剂，并确定α-生育酚和抗坏血酸的影响 补充这些水平。 最后，那些经历过 结肠肿瘤切除术后复发或 异时性良性或恶性结肠肿瘤。 我们计划找出 在一项前瞻性随机临床试验中， 他们服用维生素补充剂或安慰剂，以确定是否 这种治疗将显著降低这些疾病的发生率， 异时性肿瘤

The association of carcinoma of the colon with identifiable geographic location, and more specifically with certain dietary habits has led to the supposition that manipulation of dietary factors may help to decrease the incidence of this disease. Antioxidants have been shown to decrease the incidence of chemically-induced cancers in experimental models and decrease the level of carcinogens present in the gastric secretions and urine of certain groups of humans. With the identification of fecal mutagens in groups of patients at high risk for colon cancer, it seems possible that a decrease in the level of these mutagens may lower the incidence of colon cancer. The actual effect of non-toxic supplementation of two antioxidants, ascorbic acid and alpha-tocopherol, on the levels of these compounds in various human tissues and excretions is not clearly defined. We plan to measure the change in tissue levels of ascorbic acid and alpha-tocopherol with various levels of dietary supplementation in normal patients. We then plan to identify a population of individuals with fecal mutagens and determine the effect of alpha-tocopherol and ascorbate supplementation upon these levels. Finally, patients who have undergone removal of colonic neoplasms are at high risk for developing recurrent or metachronous benign or malignant colonic neoplasms. We plan to identify such a population and in a prospective, randomized clinical trial treat them with either vitamin supplementation or placebo to determine whether such treatment will significantly decrease the incidence of these metachronous neoplasms.