Plasma enterolignan concentrations and colorectal cancer risk in a nested case-control study

Enterolignans are biphenolic compounds that possess several biologic activities whereby they may influence carcinogenesis. The authors investigated the association between plasma enterolactone and enterodiol and colorectal cancer risk in a Dutch prospective study. Among more than 35,000 participants aged 20-59 years, 160 colorectal cancer cases were diagnosed after 7.5 years of follow-up (1987-2003). Cohort members who were frequency-matched to the cases on age, sex, and study center were selected as controls (n = 387). Plasma enterodiol and enterolactone were not associated with risk of colorectal cancer after adjustment for known colorectal cancer risk factors (highest quartile vs. lowest: for enterodiol, odds ratio = 1.11, 95% confidence interval: 0.56, 2.20 (p-trend = 0.75); for enterolactone, odds ratio = 1.70, 95% confidence interval: 0.88, 3.27 (p-trend = 0.15)). However, sex (p-interaction = 0.06) and body mass index (p-interaction < 0.01) modified the relation between plasma enterolactone and colorectal cancer risk; increased risks were observed among women and subjects with a high body mass index. The association between plasma enterodiol and colorectal cancer risk was modified by smoking status; risk was increased among current smokers (p-interaction < 0.01). These findings do not support the hypothesis that high plasma enterodiol or enterolactone concentrations are associated with reduced risk of colorectal cancer.