What are the types of stomach cancer?
Most stomach cancers are a type of cancer called adenocarcinoma, which start in the tissues that line the stomach. The three main types of stomach adenocarcinomas include:
Proximal stomach cancer. This type of cancer occurs more often in people who are obese or who have gastro-esophageal reflux disease (GERD). It starts in the first part of the stomach and may spread into the junction where the esophagus meets the stomach (gastroesophageal junction).
Noncardia (distal) stomach cancer. This type of stomach cancer may be caused by long-term inflammation in the lower part of the stomach or infection with the bacteria heliobacter pylori.
Diffuse stomach cancer. This is an aggressive form of stomach cancer that spreads throughout the wall of the stomach. It doesn’t form a tumor, so it can sometimes be hard to diagnose. It is found more often in younger people or people with an inherited syndrome that increases stomach cancer risk.