Nutrient-based dietary patterns and endometrial cancer risk: an Italian case-control study

Diet has been suggested to have a role on endometrial cancer risk, but few data are available on the role of dietary patterns on this neoplasm. A case-control study was carried out in Italy, including 454 women with endometrial cancer and 908 hospital controls admitted to the same hospitals for acute, non-neoplastic diseases. Dietary information was based on a reproducible and valid food frequency questionnaire. A posteriori dietary patterns were obtained using principal component factor analysis on 28 nutrients. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were obtained from multiple logistic regression models conditioned on age and study center, and adjusted for major known confounding factors. Positive associations were found for the "Western-type diet" (OR=1.63, 95% CI: 1.12-2.38, for the highest versus the lowest quartile category) and the "Animal-derived nutrients and polyunsaturated fatty acids" patterns (OR=1.76, 95% CI: 1.23-2.52). The corresponding risk estimates among women with a body mass index ≥30 were 2.08 (95% CI: 0.92-4.69) and 2.30 (95% CI: 1.03-5.16) for the two patterns, respectively. No association was found for the other three patterns (i.e., "Vitamins and fiber", OR=0.96, 95% CI: 0.67-1.37, "Starch-rich", OR=0.99, 95% CI: 0.69-1.42, and "Other fats", OR=1.03, 95% CI: 0.70-1.52). This study indicates that dietary habits characterized by high intakes of animal products increase endometrial cancer risk, the association being appreciably stronger for obese women.