People who have early stomach cancer that has not spread don't usually have symptoms or signs of the cancer. However, as the cancer grows, it can cause symptoms like these:
Unexplained weight loss
Abdominal pain or vague pain just above the bellybutton area
Indigestion, heartburn, or vomiting
Loss of, or decrease in, appetite
Weakness or fatigue
Blood in vomit or stool
A feeling of fullness after small meals
If you have any of these symptoms, see a doctor. They may be a sign of stomach cancer or some other medical problem.
Advanced cancer can cause a blockage in the stomach or nearby large bowel. This can lead to vomiting that doesn’t go away. Cancer can also invade the liver. In this case, jaundice (yellowing of skin and eyes) or ascites (enlargement of the belly from fluid) may be the most obvious symptoms.