A person may also have chronic nausea and pain in the middle of the abdomen. These symptoms indicate advanced disease. Most stomach cancers are found in the advanced stage. No one knows the precise reason why this cancer occurs. People from Japan are at higher risk than people from other areas.
Risk decreases when people at risk move to areas of lower risk.
This may be due to changes in diet, but this has not been proven. Cancer of the stomach is higher among people who smoke and consume alcohol than in those who do not. Avoiding all tobacco products will decrease the likelihood of developing stomach cancer. Although not proven, a diet that has fruits and vegetables as a component may also be helpful in avoiding this cancer. Some conditions are thought to lead to stomach cancer.