Relationship of serum α-tocopherol, carotenoids and retinol with the risk of breast cancer

Abstract

The relationship of serum antioxidant vitamin concentration and the risk of breast cancer was investigated in a case-control study in Korea. This study was carried out with 389 subjects consisting of 160 breast cancer patients and 229 control subjects from June 1994 to July 1995. The serum concentrations of α-tocopherol, carotenoids and retinol were measured simultaneously by a reverse phase, gradient HPLC system. Average serum concentrations of α-tocopherol, β-carotene and retinol were 7.63 ± 0.42 ug/ml, 40.5 ± 2.05 ug/dl, and 49.0 ± 4.10 ug/dl for cases and 11.0 ± 0.73 ug/ml, 48.3 ± 1.59 ug/dl and 64.6 ± 1.95 ug/dl for controls, respectively. Serum levels of α-tocopherol, β-carotene, cryptoxanthin, lutein+zeaxanthin, lycopene and retinol of breast cancer patients were significantly lower than those of controls. Odds ratios (ORs) adjusted for age, body mass index, smoking habit and alcohol drinking revealed a significant gradient of decreasing risk of breast cancer with increasing serum antioxidant vitamins. There were significant interactions between menopausal status and serum levels of antioxidant vitamins. The adjusted odds ratios for highest quintile compared with lowest quintile were 0.41 (95% CI, 0.18, 0.93) for α-tocopherol, 0.33 (95% CI, 0.15, 0.73) for β-carotene, 0.13 (95% CI, 0.06, 0.31) for zeaxanthin+lutein in premenopausal women; 0.13 (95% CI, 0.03, 0.66) for α-tocopherol, 0.28 (95% CI, 0.07, 1.12) for β-carotene, 0.12 (95% CI, 0.03, 0.58) for zeaxanthin+lutein in postmenopausal women. This results support inverse association between serum antioxidant vitamins and the risk of breast cancer in Korea and indicate that antioxidant vitamins may protect against breast cancer.