The colon is the part of your digestive system where waste material is formed. The rectum is the end of the colon which attaches to the anus. Together, the colon and rectum form the large intestine (also called the large bowel).
Cancer in the colon or rectum is called colorectal cancer (or bowel cancer).
Worldwide, cancer of the colon and rectum is the third leading cause of cancer in men and the fourth leading cause of cancer in women. The frequency of colorectal cancer varies around the world. It is common in the Western world and is rare in Asia and Africa. In countries where the population has adopted western diets, the incidence of colorectal cancer is increasing.
Cancer cells of the colon and rectum can invade and damage adjacent tissues and organs (local spread). Cancer cells can also break away and spread to other parts of the body such as the liver and lungs.
Blood from the bowel flows directly to the liver. This means the liver is a common place for colorectal cancer to spread to.
Colorectal cancer typically spreads to the liver before it spreads to other sites. Cancer has already spread to the liver in about 25% of people who are diagnosed with colorectal cancer. Secondary liver cancer is also likely to develop over time in another 25-30% of people with colorectal cancer.
However, secondary colorectal cancer is often contained in the liver before spreading to other sites. Thus, treatment directed at the liver can be very valuable and make a huge difference for many patients even though in most situations a cure cannot be achieved.
Symptoms of secondary colorectal cancer in the liver
Often secondary liver cancer does not cause any symptoms for a long period of time. If symptoms do occur, they may include:
- weight loss
- loss of appetite
- high temperature
- lethargy (extreme tiredness)
- an enlarged spleen.
Secondary liver cancer may also cause or trigger:
- Discomfort in the upper, right part of the abdomen because of an enlarged liver. This enlargement may cause pain in the right shoulder because nerves beneath the diaphragm are connected to nerves in the right shoulder. The enlarged liver stimulates the nerves in the diaphragm and causes shoulder discomfort.
- Jaundice which is a yellowish tinge to the skin and the whites of the eyes. This is caused when the bile ducts become blocked and bile produced by the liver flows back into the bloodstream. Jaundice may also cause dark-colored urine, pale-colored stools and itchy skin.
- Ascites, which is a swollen abdominal cavity caused by a buildup of fluid.
You may become confused and drowsy as toxins accumulate in the brain because the liver is too damaged to remove them from the blood. This is called liver encephalopathy.