Gastrointestinal (GI) cancer is the name for cancers that affect the digestive system.
This includes cancers of the:
- small intestine
- large intestine (large bowel or colon and rectum)
Gastro-Intestinal cancer is the most common form of cancer.
Bowel, small intestine and anal cancer
Bowel cancer is also known as colorectal cancer.
Your bowel is made up of your small and large intestine. It’s part of the body’s digestive system, which connects the stomach to the anus.
Together, the colon (large intestine) and rectum are known as the large bowel.
Most bowel cancers develop from small growths inside the colon or rectum called polyps.
These look like small spots on the bowel lining or like cherries on stalks. Not all polyps become cancerous.
A test called a colonoscopy, involving a tube inserted into the bowel, is used to test for polyps.
If polyps are detected and removed, the risk of bowel cancer is reduced.
Bowel cancer is the most common internal cancer in Australia, with over 15,000 new cases diagnosed each year.
Small intestine and anal cancers are relatively rare, each with around 400 new diagnoses a year.
Gallbladder cancer is cancer of the biliary tract.
Unfortunately, most people are diagnosed with biliary tract cancer once the tumour is too large to remove surgically or has spread to other areas of the body.
This means that only 10%-30% of people with the disease are eligible for surgery — with the aim of a cure.
Most stomach cancers develop in the cells in the inner lining of the stomach (also known as the mucosa). Stomach cancers can also be called ‘adenocarcinoma of the stomach’ or ‘gastric cancer’.
This type of cancer develops quite slowly, and it can take years before any symptoms are noticed.
The liver is a key organ in the body. It produces bile, which breaks down the fats in food so that they can be absorbed from the small intestine.
The liver also helps to process fats and proteins – as well as alcohol, some medicines, toxins and poisons. It stores glycogen which is made from sugars to fuel the body.
Primary liver cancer develops when liver cells become abnormal and form malignant tumours.
Seconday liver cancers are those which have spread from other organs, such as the colon or rectum. This spreading is known as ‘metastasis’ and it happens in about 40% of people suffering from bowel cancer.
The oesophagus is the food pipe that carries food from your mouth to your stomach. It has three main sections – upper, middle and lower.
Cancer can develop anywhere along the length of the oesophagus.
Glands in the wall of the oesophagus produce mucus, which helps your food to food slide down more easily when you’re swallowing.
Cancer that develops in the oesophagus is called ‘adenocarcinoma of the oesophagus’.
Along with squamous cell carcinoma, a type of skin cancer, oesophageal cancer is one of the most common type of cancer in Western countries (the other most common type is squamous cell carcinoma).
The pancreas is a thin, lumpy gland that lies between the stomach and spine.
It is about 13 cm long and is joined by a special duct (the pancreatic duct) to the first part of the small bowel (called duodenum).
The pancreas plays two major roles in the body: to produce insulin, which controls the amount of sugar in the blood; and to produce enzymes, which help in food digestion. Pancreatic cancer begins in the lining of the pancreatic duct.
It spreads into the body of the pancreas before moving into the blood vessels and nerves around the pancreas and can cause obstruction of the bile duct leading to jaundice.
Cancer that develops in the pancreas may also spread via the blood or the lymphatic system to other parts of the body.