review of literature on clinical pancreatology - The Pancreapedia

development indicating a field effect in carcinogenesis. Parallel linear rate patterns indicatethat the rate <strong>of</strong> cancer development is similar in all four sites even though the absoluteincidence rates vary and, regardless <strong>of</strong> location, the ductal epithelium is equally susceptibleto malignant transformation. If carcinogenic pathways to cancer are similar, then the differentincidence rates seen clinically may depend on the relative surface area <strong>of</strong> the ductal systemin these sites. Pancreatic cancers are most common because the surface area <strong>of</strong> thepancreas' ductal system is greater than that <strong>of</strong> the gallbladder, extrahepatic bile ducts, andampulla [335].Death at homeThe purpose <strong>of</strong> one study was to confirm the recent trends in home deaths among cancerdeaths in Osaka Prefecture. The number <strong>of</strong> home deaths (the proportion <strong>of</strong> home deathsamong cancer deaths) has continuously increased from 875 (4.6 %) in 1995 to 1,544 (6.6 %)in 2006. The proportions increased gradually in most second-level medical-care areas. Since2004, the proportion in the Toyono medical-care area has increased rapidly and reached10.6 percent in 2006. The proportions <strong>of</strong> cancers <strong>of</strong> the lung, colorectum, stomach, pancreasand breast gradually increased from around 5 percent in 1995 to around 7 percent in 2006[336].Etiological factorsAlthough mounting evidence suggests that insulin resistance is involved in pancreaticcarcinogenesis, few epidemiologic studies have comprehensively investigated the role <strong>of</strong>lifestyle factors influencing this metabolic disorder in the etiology <strong>of</strong> pancreatic cancer. It wasnow sought to examine this problem in a case-control study conducted in 1994-1998 inMinnesota. Cases (n=186), aged 20 years or older, were ascertained from all hospitals in themetropolitan area <strong>of</strong> the Twin Cities and the Mayo Clinic; from the latter, only cases residingin the Upper Midwest <strong>of</strong> the United States were recruited. Controls (n=554) were randomlyselected from the general population and frequency matched to cases by age (within 5years) and sex. Odds ratios (OR) and 95 % confidence intervals were estimated usingunconditional logistic regression. After adjustment for confounders, physical activity wasassociated with a reduced risk, but this protective effect was confined to light activity andmoderate activity only (OR 0.55, 95 % confidence interval 0.30 to 0.97; and OR 0.51, 95 %confidence interval 0.28 to 0.93, for highest vs. lowest quartile, respectively). An increasedrisk was found for dietary intakes <strong>of</strong> energy and fat but was statistically significant forsaturated and polyunsaturated fat only. Of note, no appreciable difference in the magnitude<strong>of</strong> the associations existed between saturated, monounsaturated, and polyunsaturated fat.Compared with individuals in the lowest quartile <strong>of</strong> fiber intake, the risk was approximatelyhalved for those in the third (OR 0.49, 95 % confidence interval 0.26 to 0.94) and the highestquartile (OR 0.52, 95 % confidence interval 0.21 to 1.30). The study lends support to thehypothesis that dietary and other lifestyle factors influencing insulin resistance modulatepancreatic cancer risk [337].Read meat and risk <strong>of</strong> cancerHigh intake <strong>of</strong> meat, particularly red and processed meat, has been associated with anincreased risk <strong>of</strong> a number <strong>of</strong> common cancers such as breast, colorectum, and prostate inmany epidemiological studies. Heterocyclic amines (HCAs) are a group <strong>of</strong> mutageniccompounds found in cooked meats, particularly well-done meats. HCAs are some <strong>of</strong> mostpotent mutagens detected using the Ames/salmonella tests and have been clearly shown toinduce tumors in experimental animal models. Over the past 10 years, an increasing number<strong>of</strong> epidemiological studies have evaluated the association <strong>of</strong> well-done meat intake and meat