PHASE II CHEMOPREVENTION TRIAL OF SE AND PROSTATE CANCER

本试验的主要目的是评估 必需微量元素硒（Se），以抑制 前列腺癌 这项试验的基本原理是基于结果 营养预防癌症（NPC）试验，我们的双盲 一项随机试验观察到前列腺 癌症发病率发生在最初10年的随访中， 接受200 μ g硒的患者与安慰剂组1相比。 该试验将患者随机分为安慰剂组和两组， 剂量为200 μ g/d和800 μ g/d。 主要终点是速度 前列腺癌进展的主要血清标志物前列腺- 特异性抗原（PSA）。 其他终点为至疾病时间 进展、开始激素治疗和至记录的时间 转移性疾病 试验的安全性终点包括 硒中毒早期症状轻微， 肝脏和肾脏酶水平。 试验将随机抽取至少220名 病人，为了有80%的能力来检测50%的 PSA速度降低，α为0.05，在平均 45个月的随访。 50%的治疗效果是 选择它是因为它是在NPC中观察到的治疗效果的一半 2年治疗滞后后的试验（RR=0.25）。

The principal purpose of this trial is to assess the potential for the essential trace element selenium (Se) to inhibit the progression of prostate cancer. The rationale for this trial is based on the results of the Nutritional Prevention of Cancer (NPC) Trial, our double blind randomized trial which observed a 63 percent reduction in prostate cancer incidence occurred during the initial 10 years of follow up in the patients receiving 200 mug of Se compared io the placebo group 1. The trial will randomize patients to either placebo or one of two Se dosages, 200 mug, and 800 mug/d. The primary endpoints is the velocity of the primary serum marker of prostate cancer progression, prostate- specific antigen (PSA). Additional endpoints are time to disease progression, initiation of hormone therapy and time to documented metastatic disease. Safety endpoints for the trial include onset of early mild symptoms of Se toxicity as well as significant changes in liver and kidney enzyme levels. The trial will randomize at least 220 patients, in order to have 80 percent power to detect a 50 percent decrease in the velocity of PSA with an alpha of 0.05, during an average of 45 months of follow up. The treatment effect of 50 percent was selected because it is half the treatment effect observed in the NPC trial after a 2 year treatment lag (RR=0.25).