Key Findings
This epidemiologic study examined the associations between enterolignans and colorectal cancer based on an observed an inverse association between plasma concentrations and colorectal adenoma risk in a case-control study. In the present study the effect modification by body mass index and smoking status were included. Plasma samples were obtained up to 15 years prior to the diagnosis of colorectal cancer. The findings of this nested case-control study do not support the hypothesis that high plasma enterodiol or enterolactone concentrations are associated with reduced risk of colorectal cancer. Further studies are needed to examine the risk associations in subgroup analysis according to sex, body mass index, and smoking status. Additionally, studies are needed to identify determinants of plasma enterolignan concentration in order to evaluate their use as biomarkers of exposure.
ABSTRACT
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.