Gastric cancer is a disease in which malignant (cancer) cells form in the lining of the stomach.
The stomach is a J-shaped organ in the upper abdomen. It is part of the digestive system, which processes nutrients (vitamins, minerals, carbohydrates, fats, proteins, and water) in foods that are eaten and helps pass waste material out of the body. Food moves from the throat to the stomach through a hollow, muscular tube called the esophagus. After leaving the stomach, partly-digested food passes into the small intestine and then into the large intestine.
The wall of the stomach is made up of 3 layers of tissue: the mucosal (innermost) layer, the muscularis (middle) layer, and the serosal (outermost) layer. Gastric cancer begins in the cells lining the mucosal layer and spreads through the outer layers as it grows.
Stromal tumors of the stomach begin in supporting connective tissue and are treated differently from gastric cancer.
Recurrent gastric cancer is cancer that has recurred (come back) after it has been treated. The cancer may come back in the stomach or in other parts of the body such as the liver or lymph nodes.