ANTIOXIDANTS IN CHEMOPREVENTION OF COLORECTAL NEOPLASMS

结肠癌与可识别的地理位置的关系 地理位置，更具体地说，某些饮食习惯导致了 假设控制饮食因素可能有助于降低 这种疾病的发病率。抗氧化剂已被证明可以降低 化学诱癌在实验模型中的发生率和降低 人的胃液和尿液中的致癌物水平 某些人类群体。与粪便致突变物的鉴定 结肠癌的高危人群，似乎有可能 降低这些诱变剂的水平可能会降低结肠癌的发生率 癌症。两种无毒补充剂的实际效果 抗氧化剂，抗坏血酸和α-生育酚，对这些水平的影响 人体各种组织和排泄物中的化合物没有明确的定义。 我们计划测量组织中抗坏血酸和抗坏血酸水平的变化 正常人群补充不同水平的α-生育酚 病人。然后，我们计划确定一组有粪便的个体 诱变剂并测定α-生育酚和抗坏血酸的作用 在这些水平上进行补充。最后，经历了 切除结肠肿瘤有很高的复发风险或 异时性的良性或恶性结肠肿瘤。我们计划找出 这样的人群并在一项前瞻性随机临床试验中治疗 服用维生素补充剂或安慰剂，以确定 这样的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.