Gastrointestinal Tract Cancer
Gastro-Intestinal (GI) cancer is a term for the group of cancers that affect the digestive system. This includes cancers of the oesophagus, gallbladder, liver, pancreas, stomach, small intestine, bowel (large intestine or colon and rectum), and anus.
Treatment for GI cancer will depend on the type of cancer, the stage or its development, and other health factors. Treatment commonly includes surgery, chemotherapy and radiation therapy.
Below is more information about types of GI cancer.
Bowel, Small Intestine and Anal Cancers
Bowel cancer is sometimes known as colorectal cancer. The bowel is part of the body’s digestive system, which connects the stomach to
the anus. Together the large colon (large intestine) and rectum are known as the bowel. Bowel cancer is a diseased growth that usually
develops inside the large bowel. Most bowel cancers develop from small growths inside the colon or rectum called polyps, which 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.
Gallbladder cancer is a cancer that starts in the gallbladder. To understand this cancer, it helps to know about the gallbladder
and what it does.
For those who are ineligible for surgery, chemotherapy remains the main treatment option. At present, there is no chemotherapy regimen that has been shown to specifically help people live longer.
Stomach Cancer, GIST and NETs
The stomach is a muscular sack-like organ that receives and stores food from the oesophagus. Once the food is broken down, it is passed from the stomach to the small bowel, where nutrients begin to be absorbed into the bloodstream.
Most stomach cancers develop in cells that line the mucosa and are called adenocarcinoma of the stomach. Stomach cancer (also known as gastric cancer) develops slowly – it may take many years before any symptoms are felt.
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 bowel. The liver helps process fats and proteins, some of which are essential for blood clotting. The liver stores glycogen which is made from sugars to fuel the body. It also helps to process alcohol, some medicines, toxins and poisons to remove them from the body.
The oesophagus is the food pipe that carries food from your mouth to your stomach. The oesophagus has three main sections – the upper, middle and lower. Cancer can develop anywhere along the length of the oesophagus.
Glands in the wall of the oesophagus produce mucus to help food slide down more easily when swallowing. These glands can become cancerous to produce adenocarcinoma of the oesophagus.
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, obstructing the bile duct. Cancer that develops in the pancreas may also spread via the blood or the lymphatic system to other parts of the body.
If diagnosed early, cancerous tumours in the pancreas are usually removed by surgery. However, this is not always possible as the cancer is often detected after it has spread from the pancreas to outlying tissues and organs.