The liver has many functions in the body, including filtering the blood, processing food, drugs and toxins, adding proteins to the blood and making bile to help digest food. Cancer can damage liver function, for example, by infiltrating normal liver tissues with cancerous tissues. If the liver begins to fail, certain noticeable changes occur in the body.
One of the liver's many functions is to break down the components of old or disfigured red blood cells. The chemical bilirubin is released by red blood cells and broken down by the liver. If the liver is unable to expel bilirubin or the red blood cells break down at a rate faster than the liver can keep up with, there will be yellowing of the skin, whites of the eyes and the underside of the tongue. When metastases invade normal liver, the decreased number of liver cells are unable to keep up with the metabolism of bilirubin, and it builds up in the blood.
Increased Abdominal Girth
The liver synthesizes many proteins for the blood. Some of the proteins regulate the fluid levels in the body, particularly by keeping fluid in the blood vessels. If the liver fails, these proteins are not made, and fluid leaks out from the blood vessels and into the surrounding tissues. In the case of liver failure from cancer, the decreased number of liver cells cannot synthesize enough proteins, and fluid leaks into the abdomen. Fluid build-up in the abdomen, called ascites, leads to increasing abdominal girth, nausea and vomiting.
Problems with Kidneys or Lungs
The liver plays such a major role in the body that without its proper function, other organs may begin to malfunction. In hepatorenal syndrome, liver failure leads to kidney failure, with increased fluid buildup in the body, weight gain, swelling and decreased urine output. In hepatopulmonary syndrome, dysfunction of the liver causes dysfunction in the lungs, which can leading to breathing complications. These issues may be compounded with cancer if metastases have also spread to the kidneys and lungs further compromising their functions.
Other proteins made by the liver work to regulate bleeding. The proteins undergo a series of chemical reactions to stop bleeding once it has started. In the case of liver failure from cancer, the decreased synthesis of these proteins from the invasion of tumor cells makes it harder for the body to stop bleeding. Once bleeding has started, it may take longer to stop the bleed and a transfusion with blood products may be required to replace the missing proteins.
Since the liver helps to clean and detoxify the blood, toxins can build up in liver failure with cancer. One toxin that has been linked to confusion, sleepiness, and disorientation during liver failure is ammonia. Ammonia is made by certain bacteria in the gut. The liver normally clears the ammonia, but with its function compromised by the burden of tumor cells, the level of ammonia in the blood can increase. One treatment is to give antibacterial drugs orally to decrease the production of ammonia in the gut.