| Abstract: |
Carotenoids, particularly lycopene, are thought to decrease prostate cancer risk, but the relationship between plasma carotenoid concentrations and risk in various populations has not been well characterized. Comparing 118 non-Hispanic Caucasian men mainly from southeast Texas with nonmetastatic prostate cancer with 52 healthy men from the same area, we conducted a case-control analysis evaluating associations between risk and plasma levels of total carotenoids, β-cryptoxanthin, α- and trans-β-carotene, lutein and zeaxanthin, total lycopenes, trans-lycopene, total cis-lycopenes, and cis-lycopene isoforms 1, 2, 3, and 5. Risk for men with high plasma levels of α-carotene, trans-β-carotene, β-cryptoxanthin, and lutein and zeaxanthin was less than half that for those with lower levels. In contrast, we observed no significant associations for total lycopenes, all-trans-lycopene, and cis-lycopene isomer peaks 2,3, and 5, although high levels of cis-lycopene isomer peak 1 were inversely associated with risk. Analysis of men with aggressive disease (Gleason scores of ≥7, n = 88) vs. less aggressive cases (Gleason scores of <7, n = 30) failed to reveal significant associations between carotenoid levels and the risk of diagnosis with aggressive disease. These findings suggest that, in these men, higher circulating levels of β-cryptoxanthin, α-carotene, trans-β-carotene, and lutein and zeaxanthin may contribute to lower prostate cancer risk but not to disease progression. Copyright © 2005, Lawrence Erlbaum Associates, Inc. |
