To investigate associations between broad dietary patterns and pancreatic cancer risk, we conducted a case-control study of 585 histologically confirmed pancreatic cancer cases and 4,779 population-based controls in 8 Canadian provinces between 1994 and 1997. Dietary intake was assessed using a FFQ. Major dietary patterns were identified by factor analysis. Unconditional logistic regression was used to describe associations between dietary pattern scores and risk of pancreatic cancer. Three dietary patterns were identified: Western, characterized by high intake of processed meats, sweets and desserts, refined grains and potatoes; fruits and vegetables, characterized by high intake of fresh fruits and cruciferous vegetables; drinker, characterized by high consumption of liquor, wine and beer. After adjustment for age, BMI, smoking, physical activity, province, educational attainment and total energy intake, the fruits and vegetables pattern was associated with a 49% reduction in pancreatic risk among men (OR ؍ 0.51, 95% CI 0. Because of its incidence and poor prognosis, pancreatic cancer is one of the most important human malignancies. Approximately 216,300 new cases occur worldwide each year. 1 In Canada in 2004, it is the fourth leading cause of cancer-related death in both men and women. 2 Survival is extremely low, with a 5-year rate of Ͻ5% 3 and a case-fatality ratio of 0.99. 2 Few risk factors for pancreatic cancer have been consistently identified. About 30% of cases are attributable to smoking. 1,4 An increased frequency of pancreatic cancer has been suggested among individuals with a long-standing history of diabetes, 5,6 chronic pancreatitis, 7,8 pernicious anemia 9 and inheritable syndromes such as familial adenomatous polyposis. 10,11 An elevated risk of pancreatic cancer has also been seen in families with a history of breast cancer and BRCA2 mutations. 12,13 It has been estimated that 30 -50% of pancreatic cancers may be due to dietary factors, 14 though for most dietary components the overall evidence is equivocal. A number of investigators have recorded a heightened risk in relation to excessive intake of fat, 15 grilled and salted/smoked red meats, 16,17 dairy products 18 and cholesterol, 19,20 though some of these associations were not confirmed in a large prospective cohort of women. 21 In contrast, pancreatic cancer risk has been found to decrease with increased consumption of fresh fruits and vegetables 20,22 as well as foods containing no preservatives or additives 19,20 and with increased carbohydrate and energy intake. 23 However, no studies to date have examined broader food consumption, which provides a more comprehensive representation of dietary intake involving a large number of dietary components working together. The present investigation was undertaken to explore the possible role of major dietary patterns in the etiology of pancreatic cancer within the Canadian NECSS.
Material and methods
Study populationThe NECSS is a multisite, population-based, case-control study involving ...