Abstract 4830: Dietary intake of dairy foods, calcium, fat, protein and risk of hepatocellular carcinoma in the European Prospective Investigation into Cancer and Nutrition (EPIC) study.
Authors: Duarte-Salles Talita , Fedirko Veronika , Trichopoulou Antonia , Bamia Christina , Romieu Isabelle , Jenab Mazda ,   on behalf of the EPIC Group
Published: August 2014

Abstract
Background: Dairy foods are an important food group whose intake may be associated with cancer. On the one hand, dairy foods are high in saturated fats and high dairy food consumption may increase circulating levels of IGF-1, a growth factor. Conversely, dairy foods contain calcium and vitamin D, which have been shown to be cancer protective at some sites. However, information on association of intake of dairy foods is limited or inconsistent for many cancer sites, such as hepatocellular carcinoma (HCC), the sixth most common malignancy and the third most common cause of cancer death worldwide.
Objective: To investigate the association between dairy foods and their components (calcium, fat and protein intakes), with incident HCC (Ncases=191) in the EPIC cohort, including a nested case-control sub-set with assessment of hepatitis B/C virus infections status.
Methods: A total of 477,206 participants were followed up for an average of 11 years. Diet was assessed by country-specific validated questionnaires. For cohort analyses, the Cox proportional hazard model was used to estimate hazard ratios (HRs) and 95% confidence intervals (95%CI). For case-control analyses, conditional logistic regression was used to calculate odds ratios (ORs) and 95%CI. All models were adjusted for relevant confounders.
Results: In the cohort study, a significant positive association for total dairy foods (highest vs. lowest tertile, HR=1.58, 95% CI:1.08-2.33; Ptrend=0.022), total dietary calcium (HR=1.74, 95%CI:1.14-2.68; Ptrend=0.009), and dairy calcium (HR per 200 g/day 1.11, 95% CI:1.02-1.20) were observed with HCC risk after multivariable adjustment. Non-significant associations were observed for milk (HR per 200g/day 1.06, 95% CI:0.95-1.17), cheese (HR per 50 g/day 1.21, 95% CI: 0.96-1.53), yoghurt (HR per 100 g/day 1.03, 95% CI:0.89-1.19), dairy fat (highest vs. lowest tertile, HR=1.36, 95% CI:0.90-2.04; Ptrend=0.290) and dairy protein intakes (HR=1.29, 95%CI:0.86-1.92; Ptrend=0.214). The results were similar after excluding individuals diagnosed with HCC within 2 years after recruitment or with self-reported diabetes at baseline. In the nested case-control study, similar results were observed among hepatitis-free individuals.
Conclusions: Results from this large prospective cohort study suggest that higher consumption of total dairy foods, total dietary calcium, and calcium from dairy sources are associated with increased HCC risk, emphasizing the role of diet in liver cancer etiology. Potential biologic mechanisms that could explain the positive associations may include circulating IGF-I or vitamin D concentrations, and require further exploration in prospective settings.
Citation Format: Talita Duarte-Salles, Veronika Fedirko, Antonia Trichopoulou, Christina Bamia, Isabelle Romieu, Mazda Jenab, on behalf of the EPIC Group. Dietary intake of dairy foods, calcium, fat, protein and risk of hepatocellular carcinoma in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4830. doi:10.1158/1538-7445.AM2013-4830