There are 4 main types of stomach cancer. These are named after the cell type in which the cancer first develops^[1]: 

• Gastric adenocarcinoma (gastric cancer) starts in the glandular cells that line the inner layer of the stomach wall (called the mucosa); it is the most common type of stomach cancer 
• Gastrointestinal stromal tumours (GIST) are rare cancers that start in the connective (interstitial) tissue in the stomach wall 
• Lymphomas are rare cancers of the lymph system that are sometimes found in the wall of the stomach 
• Carcinoid tumours are rare cancers that start in the hormone-making cells of the stomach.