Plasma levels of provitamin A and non-provitamin A carotenoids, retinol, and tocopherols in gynecologic cancers

There is strong evidence for an etiologic role of dietary nutrition, particularly anti-oxidant micronutrients in the oncogenesis and prevention of certain cancers. In the present study, we measured the plasma levels of selected provitamin A and non-provitamin A carotenoids, retinol and a-tocopherol and gammatocopherol by reversed-phase high-pressure liquid chromatography in patients with histopathologically confirmed gynecologic cancers (n=38) and in normal volunteer women with no known gynecologic pathology (n=53). The mean plasma β-carotene, lycopene, canthaxanthin and a-tocopherol levels were significantly (p <0.012, p <0.004, p <0.007, and p <0.001, respectively, by ANOVA) lower in patients with carcinoma of the cervix, endometrium or ovary compared with the mean plasma levels in controls. However, the mean plasma gamma-tocopherol level was significantly lower (p <0.05) only in ovarian cancer patients and the plasma retinol levels were comparable among all subjects. These findings suggest that selected micronutrients may be acting as antioxidant to quench and protect against free radical-induced carcinogenic gene mutations in human gynecologic carcinomas. Further studies of the role(s) of these antioxidant vitamins at the molecular level are required.