Dietary Factors and Risk of Pancreatic Cancer in a Pooled Analysis

DESCRIPTION (provided by applicant): Insulin and insulin like growth factor (IGF-1), and Vitamin D, have been hypothesized to be associated with risk of pancreatic cancer. High levels of insulin and IGF-1 may stimulate cell division, promote tumor development and increase local blood flow, while high levels of Vitamin D may reduce proliferation, angiogenesis and invasiveness, and increase differentiation and apoptosis. Dietary factors, such as sugar-sweetened beverages and dairy products, may modify the levels of these hormones and thus, ultimately impact cancer risk. Few studies, particularly those using a prospective design, have examined the association between these dietary factors (e.g. soft drinks, dairy products, vitamin D) and pancreatic cancer risk;results have been heterogeneous. In this application, we will examine associations between dietary factors related to insulin and IGF-1 (e.g., sugar sweetened beverages) and vitamin D (dairy products, vitamin D, calcium) and pancreatic cancer risk. We will further examine whether obesity, physical activity, and smoking status modify the association between these dietary factors and pancreatic cancer risk. These aims will be conducted within 14 studies in the Pooling Project of Prospective Studies of Diet and Cancer (Pooling Project), an international consortium of cohort studies. The Pooling Project allows for prospective evaluation of dietary factors with rarer cancers, such as pancreatic cancer, by combining data from multiple studies. Also, the Pooling Project creates an environment where the definitions and modeling of the cohorts'exposures, covariates and outcomes are standardized, particularly important when discrepancies that are present in the literature may be due to different reference groups, cutoffs, exposure or outcome definitions across studies. The pancreatic cancer dataset for the Pooling Project has already been established;these cohorts provided dietary data from 869,694 individuals among whom 2,187 pancreatic cancer cases were identified during follow-up. Currently, we have data on over 40 nutrients, the foods on each FFQ, and over 40 potential cancer risk factors. Thus, the Pooling Project will provide an opportunity to examine in detail the associations between these dietary factors and pancreatic cancer risk with a large number of cases. Using this existing dataset in the Pooling Project to examine these aims will greatly expand on the dearth of literature and prospective data available on these associations using a cost- and time-efficient approach. Thus, this analysis may provide insight into the etiology of pancreatic cancer and ultimately aid in prevention of this highly fatal cancer.