Latitude and pancreatic cancer

With regard to the geographical distribution of pancreatic cancer mortality, the relationship of the latitude and of the average temperature to pancreatic cancer mortality was examined. Both internationally and within Japan, a strong positive association between latitude and pancreatic cancer mortality and a strong negative association with the average temperature were observed. The simple correlation coefficient between pancreatic cancer mortality and the latitude was 0.724 for males and 0.725 for females, and that between pancreatic cancer mortality and the average temperature was -0.773 for males and -0.729 for females in 26 countries. In the 47 prefectures in Japan, the coefficient was 0.612, 0.615, -0.589, and -0.630 respectively. Most of these relationships remained statistically significant after controlling for per capita consumption of food which was also related to the pancreatic cancer mortality internationally, such as sugar, eggs, milk and dairy products, oils and fats, pulse, coffee, and fat. Within Japan, an urban-rural effect on the pancreatic cancer mortality was not observed in spite of a higher intake of fat in large cities. There remains the possibility that factors related to latitude or average temperature other than diet may be involved in the occurrence of pancreatic cancer.