SELECT: the Selenium and Vitamin E Cancer Prevention Trial: rationale and design

摘要: Prostate cancer is the commonest non-skin malignancy in United States and has a substantial mortality rate despite use of PSA-based screening. Furthermore, therapy for prostate by surgery, radiotherapy or hormonal manipulation carries significant risk treatment-related morbidity. Recent analysis secondary endpoints several large-scale randomized prospective clinical trials other malignancies suggested that selenium vitamin E may result decreased incidence from cancer. In vitro preclinical studies these antioxidants support this hypothesis. This review outlines rationale design SELECT, Selenium Vitamin Cancer Prevention Trial, designed to test hypothesis alone combination can reduce population-based cohort men at risk. SELECT phase III, randomized, double-blinded, prospective, 2x2 factorial trial which will randomize 32,400 healthy with normal DRE serum PSA one four study arms: alone, selenium+vitamin E, placebo. Study agents be taken orally minimum 7 maximum 12 y assessments general health, incident toxicity performed month intervals. Under assumptions described, detectable reduction 25% an effective single agent relative placebo, additional agent. The estimated power comparison vs placebo 96% 89%. Secondary include cancer-free survival, all-cause mortality, cancers diseases potentially impacted chronic E. Other objectives periodic quality life assessments, assessment micronutrient levels risk, evaluation biological genetic markers Prostatic Diseases (2000) 3, 145-151