Risk factors from geographic epidemiology for gastrointestinal cancer.

The incidence of gastrointestinal cancers differ greatly internationally. Blacks have higher rates than whites for esophagus, stomach, liver, and pancreatic cancer in the U.S. Differences also occur between other racial groups. Studies on migrants suggest environmental causes for these differences. Stomach cancer rates have fallen, intestine cancer is stable, pancreatic cancer rates rose, but are now falling in males. The incidence of colon, rectal, breast, corpus-uterus, ovary, and prostate cancer are positively correlated, but colon or rectal and stomach cancer are negatively correlated. Colon and rectal cancer mortality are positively and stomach cancer negatively associated with social class. Esophageal, liver, colon, and pancreatic cancer in males are higher in urban areas. Seventh Day Adventists and Mormons show a low risk of colon cancer. Internationally intake of fat is correlated with colon, rectal, and pancreatic cancer, and starch with stomach cancer.