Phytoestrogens and liver disease

Abstract

Phytoestrogens are plant substances that are similar to 17-beta-estradiol and produce estrogenic effects. A protective role in the development of breast and prostate cancer has been hypothesized. Estrogen receptors and their variant forms play a significant role in the pathogenesis of hepatocellular carcinoma (HCC); therefore weak estrogenic substances in the diet may play a role in its development. To investigate the role of phytoestrogens in HCC an investigation of dietary intake of these substances has been performed. Cases, patients at first diagnosis of cirrhosis or HCC were chosen. Questionnaire was built up using indications from previously published papers, extending the registration of details of the diet to reconstruct intake of nutrients for the last year. Interviews were always performed by the same dietician. Quantities determined with the help of photos of servings. Data were analyzed with Winfood database completed with data regarding content in phytoestrogens of food, beverages and seasonings. So far 92 cirrhotic patients and 32 HCCs have been interviewed. No significant difference was registered among the two groups regarding total caloric intake or single nutrients (lipids, carbohydrates, proteins). A significant lower intake of genistein was evidenced in patients at first diagnosis of HCC in comparison with cirrhotics; no significant difference was found in daidzein intake. Lignans intake was strictly related with wine intake; intake was significantly lower in cases only when wine was taken into account otherwise it was similar. Results can be summarized as follows: (1) there are no clear-cut differences (both qualitative or quantitative) between cirrhotics and HCC patients in the overall daily caloric intake while; (2) definite differences exist in the intake of some of the phytoestrogens (genistein, SEC, MAT); (3) differences between cases and controls in SEC and MAT are mainly attributable to lower alcohol intake in cases while; (4) significantly lower genistein intake in HCC only seems due to personal preferences of patients. In conclusion, these differences that we have evidenced in the diet in regard to estrogen-like substances may be relevant in modulating the risk of developing HCC in cirrhotic patients.