of Gastric Cancer
The stomach is part of the digestive system. Food passes through the esophagus into the stomach at the level of the diaphragm, which is the breathing muscle that separates the abdomen from the chest. The stomach extends from the diaphragm to the duodenum, which is the first portion of the small intestine.
Cancer of the stomach is called gastric cancer. Gastric adenocarcinoma is the most common cancer of the stomach and it arises from the cells (columnar epithelium) lining the surface of the stomach. The primary risk factor associated with gastric cancer is infection with the bacterium, Helicobacter pylori (H. pylori). H. pylori can be treated with antibiotics, which may reduce the risk of gastric cancer.1
There has been a marked decline in the incidence of gastric cancer in the United States and many other industrialized nations over the past 20-30 years. However, there has been an increase in cancers arising at the junction of the esophagus with the stomach. Approximately 21,000 new cases of gastric cancer are diagnosed in the United States each year, with approximately 10,500 yearly deaths from gastric cancer.2
Gastric cancer is more common and is a major cause of cancer-related death in Asian countries such as Korea, China, Taiwan and Japan. Thus, much of the knowledge about treatment, especially surgery, comes from these countries. The incidence of gastric cancer is so high in these countries that they perform routine screening by esophagoscopy for detection of early gastric cancer. Early detection programs, such as those implemented in Japan, are not practiced elsewhere in the world because of the lower incidence of gastric cancer. For this reason, gastric cancer is detected at a later stage (extent of spread) in the U.S. and Europe than in Japan.
Surgery is the primary treatment of gastric cancer. Two main factors affect outcome following surgery for gastric cancer, the depth of the penetration of the primary cancer into the wall of the stomach and the presence or absence of spread of cancer to regional or adjacent lymph nodes. The site of the primary cancer also influences outcome, as upper stomach cancers are associated with a worse outcome than cancers of the middle and lower stomach.
1 American Cancer Society. Cancer Facts & Figures 2017.