Early stage gastric cancer rarely has symptoms, and cancer with ulcers can cause signs of peptic ulcer, such as heartburn, hunger pain, etc. but those signs are well controlled with antacid. Gastric cancer has no specific symptom. As it develops further, however, it may has progressive systemic symptoms, such as poor appetite, weight loss, anemia, etc. with symptoms of discomfort in the upper abdomen, abdominal distention, pain, indigestion, etc. Also, it is not unusual that patients see doctors when they have symptoms of advanced stage, such as vomiting caused by pyloric obstruction, hematemesis or bloody excrement caused by internal bleeding, dysphagia caused by invading into cardiac region, abdominal mass palpation, hepatomegaly, intraperitoneal lymph nodes palpation.
It is known that heredity, chronic gastritis, gastrointestinal dysplasia (state in which cells of small intestine appear in the gastric mucosa), gastroenteroanastomosis, diet factors(nitrate, high salt food, burnt food, etc.), Helicobacter pylori infection, smoking, excessive exposure to radiation etc. affect to the development of gastric cancer.