Stomach cancer develops when cells in the lining of the stomach grow and divide in an abnormal way. Tumours can begin anywhere in the stomach, although most start in the glandular tissue found on the stomach’s inner surface (mucosa). This type of cancer is called adenocarcinoma of the stomach (also known as gastric cancer).
If it is not found and treated early, stomach cancer can spread through the lymphatic system to nearby lymph nodes or through the bloodstream to other parts of the body, such as the liver and lungs. It may also spread to the walls of the abdomen (peritoneum). Rarely, it can grow through the stomach wall into nearby organs such as the pancreas and bowel.
Learn more about:
- Rare types of stomach cancer
- Who gets stomach cancer?
- What causes stomach cancer?
- The oesophagus and stomach
Rare types of stomach cancer
Some less common types of cancer can affect the stomach. These include small cell carcinomas, lymphomas, neuroendocrine tumours and gastrointestinal stromal tumours. These types of cancer aren’t discussed here and treatment may be different. For more information, call Cancer Council 13 11 20.
Some cancers start at the point where the stomach meets the oesophagus (the gastro-oesophageal junction). Depending on the type of gastro-oesophageal cancer, it may be treated similarly to stomach cancer. For more information about your situation, talk to your treatment team.
How gets stomach cancer?
About 2200 people are diagnosed with stomach cancer in Australia each year. Men are twice as likely as women to be diagnosed with stomach cancer. It is more common in people over 60, but it can occur at any age.
About one in 130 men and one in 300 women are likely to develop stomach cancer before the age of 75.
What causes stomach cancer?
Some of the risk factors that may lead to stomach cancer include:
- older age (being over 60)
- infection with Helicobacter pylori (H. pylori), a type of bacteria found in the stomach
- having had a subtotal gastrectomy (see page 25) to treat non-cancerous conditions
- smoking
- low red blood cell levels (pernicious anaemia)
- a family history of stomach cancer
- having an inherited genetic condition such as familial adenomatous polyposis (FAP), Lynch syndrome, gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS) or hereditary diffuse gastric cancer (HDGC)
- chronic inflammation of the stomach (chronic gastritis)
- being overweight or obese
- drinking alcohol
- eating foods preserved by salting
The oesophagus and stomach
The oesophagus and stomach are part of the upper gastrointestinal (GI) tract, which is part of the digestive system. The digestive system helps the body break down food and turn it into energy.
The oesophagus (food pipe or gullet) is a long, muscular tube. It moves food, fluid and saliva from the mouth and throat to the stomach. A valve (sphincter) at the end of the oesophagus stops acid and food moving from the stomach back into the oesophagus.
The stomach is a hollow, muscular sac, located between the end of the oesophagus and the beginning of the small bowel. The stomach expands to store and help digest food that has been swallowed. It also helps the body absorb some vitamins and minerals.
Juices in the stomach break down food into a thick fluid, which then moves into the small bowel. In the small bowel, nutrients from the broken-down food are absorbed into the bloodstream. The waste matter moves into the large bowel, where fluids are absorbed into the body. The solid waste matter is passed out of the body as a bowel movement.
The oesophageal wall has three layers of tissue and an outer covering known as the adventitia. The stomach wall has four layers of tissue.
|
Layer |
In oesophagus | In stomach |
| 1. mucosa (moist innermost layer) |
|
|
| 2. submucosa (supports the mucosa) |
|
|
| 3. muscle layer |
|
|
| 4. outer covering/ layer |
|
|
Key resource
Download a PDF booklet on this topic.
More resources
Prof David Watson, Senior Consultant Surgeon, Oesophago-gastric Surgery Unit, Flinders Medical Centre, and Matthew Flinders Distinguished Professor of Surgery, Flinders University, SA; Kate Barber, 13 11 20 Consultant, Cancer Council Victoria; Katie Benton, Advanced Dietitian, Cancer Care, Sunshine Coast Hospital and Health Service, QLD; Alana Fitzgibbon, Clinical Nurse Consultant, Gastrointestinal Cancers, Royal Hobart Hospital, TAS; Christine Froude, Consumer; Dr Andrew Oar, Radiation Oncologist, Icon Cancer Centre, Gold Coast University Hospital, QLD; Dr Spiro Raftopoulos, Interventional Endoscopist and Consultant Gastroenterologist, Sir Charles Gairdner Hospital, WA; Grant Wilson, Consumer; Prof Desmond Yip, Clinical Director, Department of Medical Oncology, The Canberra Hospital, ACT. We also thank the health professionals, consumers and editorial teams who have worked on previous editions of this title.
View the Cancer Council NSW editorial policy.
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