van den Brandt Piet A, Zeegers Maurice P A, Bode Peter, Goldbohm R Alexandra
Department of Epidemiology, Maastricht University, 6200 MD Maastricht, The Netherlands.
Cancer Epidemiol Biomarkers Prev. 2003 Sep;12(9):866-71.
Results of a randomized controlled trial have suggested a protective effect of selenium against prostate cancer. Few other prospective studies have been conducted to confirm or refute this. The association between prostate cancer and baseline toenail selenium level was evaluated in the Netherlands Cohort Study, conducted among 58,279 men, aged 55-69 years at entry. In September 1986, the cohort members completed a questionnaire on risk factors for cancer and provided toenail clippings for determination of baseline selenium status. After 6.3 years of follow-up, 540 incident prostate carcinoma cases and 1,211 subcohort members with complete toenail selenium data were available for case-cohort analyses. In multivariate survival analysis, an inverse association between toenail selenium level and prostate cancer risk was observed. Incidence rate ratios in increasing selenium quintiles were 1.00 (ref), 1.05, 0.69, 0.75, and 0.69 (95% confidence interval, 0.48-0.99), respectively (P-trend=0.008). This association persisted after exclusion of cases diagnosed during early follow-up. The inverse association was more pronounced in ex-smokers than current smokers, and unclear in never-smokers. Analysis of effect modification by intake of antioxidant vitamins C, E, and the carotenoids alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, and lutein/zeaxanthin showed a strong, significant interaction with beta-cryptoxanthin, and to a lesser extent with vitamin C. These results confirm the hypothesis that higher selenium intake may reduce prostate cancer risk. Future research on optimum dose level is needed.
一项随机对照试验的结果表明，硒对前列腺癌具有保护作用。很少有其他前瞻性研究来证实或反驳这一点。在荷兰队列研究中，对58279名年龄在55至69岁之间的男性进行了前列腺癌与基线脚趾甲硒水平之间关联的评估。1986年9月，队列成员完成了一份关于癌症危险因素的问卷，并提供了脚趾甲剪片用于测定基线硒状态。经过6.3年的随访，有540例前列腺癌新发病例以及1211名具有完整脚趾甲硒数据的亚队列成员可用于病例-队列分析。在多变量生存分析中，观察到脚趾甲硒水平与前列腺癌风险之间呈负相关。硒五分位数增加时的发病率比分别为1.00（参照）、1.05、0.69、0.75和0.69（95%置信区间，0.48 - 0.99）（P趋势 = 0.008）。排除早期随访期间诊断出的病例后，这种关联依然存在。这种负相关在既往吸烟者中比当前吸烟者中更为明显，在从不吸烟者中则不明确。对抗氧化维生素C、E以及类胡萝卜素α-胡萝卜素、β-胡萝卜素、β-隐黄质、番茄红素和叶黄素/玉米黄质摄入的效应修饰分析显示，与β-隐黄质存在强烈的显著相互作用，与维生素C的相互作用程度较小。这些结果这些结果证实了较高硒摄入量可能降低前列腺癌风险这一假设。未来需要对最佳剂量水平进行研究。
