Article

A Nutrient Approach to Prostate Cancer Prevention: The Selenium and Vitamin E Cancer Prevention Trial (SELECT)

Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland 20892, USA.
Nutrition and Cancer (Impact Factor: 2.32). 10/2010; 62(7):896-918. DOI: 10.1080/01635581.2010.509833
Source: PubMed

ABSTRACT

The Selenium and Vitamin E Cancer Prevention Trial (SELECT) randomized 35,533 healthy men, >55 yr old (>50 yr if African American), with normal digital rectal exams and prostate specific antigens <4 ng/ml to 1) 200 μg/day l-selenomethionine, 2) 400 IU/day all-rac-alpha-tocopheryl acetate (vitamin E), 3) both supplements, or 4) placebo for 7 to 12 yr. The hypotheses underlying SELECT, that selenium and vitamin E individually and together decrease prostate cancer incidence, derived from epidemiologic and laboratory evidence and significant secondary endpoints in the Nutritional Prevention of Cancer (selenium) and Alpha-Tocopherol Beta-Carotene (vitamin E) trials. In SELECT, prostate cancer incidence did not differ among the 4 arms: hazard ratios [99% confidence intervals (CIs)] for prostate cancer were 1.13 (99% CI = 0.95-1.35, P = 0.06; n = 473) for vitamin E, 1.04 (99% CI = 0.87-1.24, P = 0.62; n = 432) for selenium, and 1.05 (99% CI = 0.88-1.25, P = 0.52; n = 437) for selenium + vitamin E vs. 1.00 (n = 416) for placebo. Statistically nonsignificant increased risks of prostate cancer with vitamin E alone [relative risk (RR) = 1.13, P = 0.06) and newly diagnosed Type 2 diabetes mellitus with selenium alone (RR = 1.07, P = 0.16) were observed. SELECT data show that neither selenium nor vitamin E, alone or together, in the doses and formulations used, prevented prostate cancer in this heterogeneous population of healthy men.

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    • "In spite of the evidence outlined above, there is some controversy related to the hypotheses that Se and other compounds, such as Vitamin E, decrease PC incidence either individually or in combination. For example, Dunn et al. [75] reported that neither Se nor Vitamin E (SELECT), alone or together, prevented PC in a study carried out on a heterogeneous population of healthy men. Stratton et al. [76] also observed that Se supplementation to 140 men distributed into a placebo group and two groups that received different amounts of Se did not show a protective effect in subjects with localized PC. "
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