Lack of prospective associations between plasma and urinary phytoestrogens and risk of prostate or colorectal cancer in the European Prospective into Cancer-Norfolk study.
Dietary phytoestrogens are suggested to reduce the risk of prostate and colorectal cancer, but the results of epidemiologic studies have not yielded consistent support for this proposed effect, possibly due to inadequate databases of phytoestrogen levels in foods. Biomarkers of phytoestrogen intakes may provide a clearer insight into the relationship between phytoestrogen exposure and the risk of prostate or colorectal cancer risks. From the European Prospective into Cancer-Norfolk cohort (ages 45-75), serum and urine samples were analyzed for seven phytoestrogens [daidzein, enterodiol, enterolactone, genistein, glycitein, O-desmethylangolensin (O-DMA), and equol] among 193 cases of prostate cancer and 828 controls, and 221 cases of colorectal cancer with 889 controls. Summary variables of total lignans (enterodiol and enterolactone) and total isoflavones (daidzein, genistein, O-DMA, equol, and glycitein) were created and analyzed in conjunction with individual phytoestrogens. Logistic regression analyses revealed that there was no significant association between prostate cancer risk and total serum isoflavones [odds ratio (OR), 1.01; 95% confidence interval (CI), 0.93-1.10] or total serum lignans (OR, 0.94; 95% CI, 0.86-1.04) or between colorectal cancer risk and total serum isoflavones (OR, 1.01; 95% CI, 0.94-1.08) or total serum lignans (OR, 1.03; 95% CI, 0.94-1.12). Similarly, null associations were observed for individual serum phytoestrogens and for all urinary phytoestrogen biomarkers. In conclusion, we have found no evidence to support an inverse association between phytoestrogen exposure and prostate or colorectal cancer risk.
MRC Centre for Nutrition and Cancer, Department of Public Health and Primary Care, Institute of Public Health, University of Cambridge, Strangeways Research Laboratory, Wort's Causeway, Cambridge CB1 8RN, United Kingdom. heather.ward@srl.cam.ac.uk
Heather
H
Ward
Gaelle
G
Chapelais
Gunter G C
GG
Kuhnle
Robert
R
Luben
Kay-Tee
KT
Khaw
Sheila
S
Bingham
D000368:Aged; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000097:blood* / Q000453:epidemiology / Q000652:urine*; D004739:England / Q000453:epidemiology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D048789:Phytoestrogens / Q000097:blood* / Q000652:urine*; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000097:blood* / Q000453:epidemiology / Q000652:urine*; D012042:Registries; D012306:Risk
D048789:Phytoestrogens