The cause of a secondary cancer is always a primary cancer somewhere else in the body. If the cancer cells pass into the bloodstream, the liver is a likely place for them to settle.
If you have secondary liver cancer you may find it helpful to read this section together with the section for your primary cancer (where the cancer started).
Sometimes, even with thorough medical tests, it's not possible to find out where the cancer started. This is sometimes known as cancer of unknown primary.
Occasionally cancer can start in the liver; this is known asprimary liver cancer. Primary liver cancer is relatively rare while secondary liver cancer is much more common.
Symptoms of secondary cancer in the liver
Secondary cancer in the liver may not cause any symptoms for a long time, and it may only be discovered by routine tests.
Symptoms that might occur include loss of appetite, weight loss, feeling sick (nausea) and tiredness (fatigue). Some people may also have a high temperature and feel shivery.
People sometimes notice a vague discomfort in the upper abdomen, which may become painful. This is due to the liver becoming enlarged. Pain can sometimes also be felt in the right shoulder; this is known as referred pain. It's due to the enlarged liver stimulating the nerves beneath the diaphragm (the sheet of muscle under the lungs), which are connected to nerves in the right shoulder.
If the bile duct becomes blocked, bile produced by the liver will flow back into the bloodstream, causing jaundice. This will make the skin and whites of the eyes turn yellow and may make the skin very itchy. Other signs of jaundice are dark-coloured urine and pale stools (bowel motions).
Sometimes, fluid builds up in the abdomen and causes swelling known as ascites. There may be several possible reasons for this:
- If cancer cells have spread to the lining of the abdomen, they can irritate it and cause fluid build-up.
- If the liver is affected by cancer cells, there may be an increase in pressure in the veins that lead to it. Fluid from the abdomen then can't pass quickly enough through the liver, so it starts to collect in the abdomen.
- If the liver is damaged, it may produce less blood protein. This can upset the body's fluid balance and cause fluid to build up in the body tissues, including the tissues of the abdomen.
- Cancer cells may block the lymphatic system. The lymphatic system is a network of fine channels throughout the body. One of its functions is to drain off excess fluid, which is eventually passed out of the body in urine.
If some of these channels are blocked, the system can't drain efficiently and fluid may build up.
If ascites develops, a tube can be put into your abdomen to drain the fluid away.
Whatever the cause, jaundice or ascites will always show a condition that needs medical attention and so should not be ignored. If you have these symptoms, get them checked by your doctor.
*Information provided by Macmillan cancer support