Prostate Cancer Prevention and the Selenium and Vitamin E Cancer Prevention Trial (SELECT): A Selenium Perspective

摘要: The Selenium and Vitamin E Cancer Prevention Trial (SELECT) randomized 35,533 healthy men, ≥55 years (≥50 if African American), with normal digital rectal exams prostate-specific antigens <4 ng/mL, to (i) 200 μg/day l-selenomethionine, (ii) 400 IU/day all-rac-alpha-tocopheryl acetate (vitamin E), (iii) both supplements, or (iv) placebo for a median of 5.5 (range 4.2–7.3 years). hypotheses underlying SELECT, that selenium vitamin individually together decrease prostate cancer incidence, derived from epidemiologic laboratory evidence significant secondary endpoints in the Nutritional (NPC) (selenium) Alpha-Tocopherol Beta-Carotene E) trials. Results SELECT showed incidence did not differ among four arms: hazard ratios (HRs) (99% CIs) cancer: 1.13 CI, 0.95–1.35; p = 0.06; n 473) E, 1.04 0.87–1.24; 0.62; 432) selenium, 1.05 0.88–1.25; 0.52; 437) + vs. 1.00 (n 416) placebo. Statistically nonsignificant increased risks alone (RR 1.13; 0.06) newly diagnosed type 2 diabetes mellitus 1.07; 0.16) were observed. data show neither nor together, doses formulations used, prevented this heterogeneous population men. Although there are many potential explanations null findings most likely reasons appear be mismatch between target intervention agents selected, effects limited as-yet-undetermined subgroups susceptible