|
Reference Study Country |
Design N randomised/completed Duration(a) Recruitment criteria |
Subject characteristics at baseline(b) | Intervention(b) | Outcomes assessed | Results |
|---|---|---|---|---|---|
|
Algotar et al. (2013b) NBT USA and New Zealand |
RCT G1, placebo: 232/0 G2, 200 μg Se/d: 234/0 G2, 400 μg Se/d: 233/0 Duration (median): 35 mo High risk of prostate cancer, as evidenced by PSA > 4 ng/mL and/or suspicious DRE and/or PSA velocity > 0.75 ng/mL per yr; negative prostate biopsy for cancer within 12 mo of enrolment. |
Sex: M Age (yr) G1: 65.5 ± 7.4 G2: 65.2 ± 8.0 G3: 65.5 ± 7.7 BMI (kg/m 2 ): NR Ethnicity (Caucasians, %) G1: 84.2 G2: 83.7 G3: 82.6 Plasma Se (μg/L) G1: 124.5 ± 24.7 G2: 126.6 ± 26.9 G3: 127.2 ± 24.8 PSA (ng/mL) G1: 6.4 (5.6) G2: 7.2 (6.2) G3: 6.9 (4.5) Se intake: NR |
Selenised yeast (200 μg Se/d or 400 μg Se/d or) vs placebo Adherence, pill counts (%) G1: 92.1 G2: 93.2 G3: 91.2 |
Incidence of prostate cancer, biopsy‐proven (primary endpoint). Tissue samples from the subject's qualifying biopsy requested from the subject's physician and compiled in a biospecimen repository. |
HR for risk of prostate cancer (95% CI) (adjusted for age at baseline, race, baseline PSA, and baseline plasma Se concentration) G1: 1 (ref) G2: 0.94 (0.52, 1.7) G3: 0.90 (0.48, 1.66) |
|
Lippman et al. (2009) Klein et al. (2011) SELECT USA, Canada, Puerto Rico |
RCT G1, placebo: 8,856/8,696 G2, 200 μg Se/d: 8,910/8,752 Duration (median (min‐max)): 5.46 (4.17–7.33) yr (+ additional 3 yr of follow up) Aged ≥ 50 yr (African American men) or 55 yr or older (all other men); serum PSA ≤4 ng/mL; DRE not suspicious for prostate cancer |
Sex: M Age (yr, median (IQR)) G1: 62.6 (58.1–67.8) G2: 62.6 (58.2–68.0) BMI (kg/m 2 ): NR Ethnicity (Caucasian, %): 79 Serum Se (μg/L, median (IQR)) G1: 137.6 (124.7–151.8) G2: 135.0 (123.4–145.9) PSA (ng/mL, mean (IQR)) G1: 1.1 (0.6–1.9) G2: 1.1 (0.6–1.9) Se intake: NR |
L‐selenomethionine (200 μg Se/d) vs placebo Adherence, pill counts (%) G1: 85% at yr 1; 69% at yr 5 G2: 84% at yr 1; 69% at yr 5 Serum Se at 4 yr, μg/L (median (IQR)) G1: 140.1 (124.3–150.8) G2: 251.6 (218.7–275.0) |
Incidence of prostate cancer determined by routine clinical management. Prostate cancer status was determined by self‐report at each 6‐mo study visit; pathology report and tissue forwarded to the central pathology laboratory for confirmation of diagnosis |
N prostate cancer cases; HR for risk of prostate cancer (95% CI) By end of intervention period: G1: 416¦G2: 432; 1.04 (0.90, 1.18), p = 0.62 Intervention period + 3 yr of follow up: G1: 529¦G2: 575; 1.09 (0.93, 1.27), p = 0.18 Of which, prostate cases with Gleason ≥7 G1: 133¦G2: 161; 1.21 (0.90, 1.63), p = 0.11 |
|
Marshall et al. (2011) USA |
RCT G1, placebo: 225/134 G2, 200 μg Se/d: 227/135 Duration: 3 yr Aged ≥ 40 yr; biopsy‐ confirmed diagnosis of high‐grade prostatic intraepithelial neoplasia with no evidence of cancer; PSA ≤ 10 ng/mL; AUA symptom score < 20; ambulatory and able to carry out work of a light or sedentary nature. |
Sex: M Age (yr): ≥ 40 BMI < 25¦> 30 kg/m 2 (%) G1: 26.1¦27.5 G2: 21.7¦26.4 Ethnicity (White, %) G1: 76.8 G2: 83.5 Plasma Se, μg/L (median (IQR)) G1 (n = 51): 135.2 (113.3, 166.8) G2 (n = 46): 138.1 (104.7, 166.4) PSA < 4 ng/mL¦4–10 ng/mL (%) G1: 42.6¦57.4 G2: 38.2¦61.8 Se intake NR |
Selenomethionine (200 μg Se/d) vs placebo Adherence, pills count (%), at 1 yr; 3 yr G1: 90.8; 81.3 G2: 90.5; 78.9 Plasma Se (median, μg/L), at 1 yr; 3 yr G1 (n = 51): 145.7; 152.1 G2 (n = 46): 240.4; 261.2 |
Incidence of prostate cancer; biopsy proven. DRE every 6 mo. Tissue blocks and corresponding pathology reports for all prostate procedures submitted to the central study pathologist for review (blinded to study assignment) |
N prostate cancer cases; RR for prostate cancer (95% CI) G1: 47¦G2: 45; 0.97 (0.68, 1.39) By quartile of baseline plasma Se < 106 μg/L G1: 11¦G2: 9; 0.82 (0.40, 1.69) 106–132 μg/L G1: 9¦G2: 12; 1.38 (0.68, 2.78) 132–162 μg/L G1: 16¦G2: 14; 0.98 (0.58, 1.68) > 162 μg/L G1: 11¦G2: 10; 0.91 (0.45, 1.84) |
|
Duffield‐Lillico et al. (2003a) NPC USA |
RCT G1, placebo: 470 G2, 200 μg Se/day: 457 Duration (mean, max): 7.6 yr, 13 yr Confirmed histories of nonmelanoma skin cancer within the year before randomisation; estimated 5‐year life‐expectancy; no cancer within the previous 5 years. |
Sex: M Age (yr) G1: 63.7 ± 9.4 G2: 64.9 ± 8.8 BMI (kg/m 2 ) G1: 25.9 ± 3.7 G2: 26.0 ± 3.6 Ethnicity: NR Plasma Se (μg/L) G1: 115.1 ± 22.0 G2: 115.1 ± 22.1 PSA (ng/mL) G1: 1.9 (3.3) G2: 2.0 (3.4) Se intake: NR |
Selenised yeast (200 μg Se/d) vs placebo Adherence NR |
Participants visited the clinics every 6 mo and reported new illnesses and medications; medical records documenting any cancer screening procedures (PSA tests, DRE, prostate biopsies and surgery) obtained throughout the course of the trial. Incident prostate cancer cases reviewed and staged by a urological oncologist according to the TNM system. |
N prostate cancer cases; HR for prostate cancer (95% CI) (adjusted for age and smoking) G1: 42¦G2: 22; 0.48 (0.28, 0.80) By tertile of baseline plasma Se ≤ 106.4 μg/L G1: 15¦G2: 2; 0.14 (0.03, 0.61) 106.8–123.2 μg/L G1: 16¦G2: 7; 0.33 (0.13, 0.82) > 123.2 μg/L G1: 11¦G2: 13; 1.14 (0.51, 2.59) |
AUA: American Urological Association; BMI: body mass index; CI: confidence interval; d: day; DRE: digital rectal examination; Gx: group x; HR: hazard ratio; IQR: interquartile range; M: males; mo: month; NBT: Negative Biopsy Trial; NPC: Nutritional Prevention of Cancer Trial; NR: not reported; PC: prostate cancer; PSA: prostate specific antigen; RCT: randomised controlled trial; Se: selenium; SELECT: Selenium and Vitamin E Cancer Prevention Trial; TNM: tumour, nodes, and metastases; USA: United States of America; yr: year.
(a) Duration = duration of the treatment phase, unless specified otherwise.
(b): Mean ± SD, unless specified otherwise.