What is Liver Cancer?
The liver is the largest organ in the body. It is found behind the ribs on the right side of the abdomen. The liver has two parts, a right lobe and a smaller left lobe.
The liver has many important functions that keep a person healthy. It removes harmful material from the blood. It makes enzymes and bile that help digest food. It also converts food into substances needed for life and growth.
The liver gets its supply of blood from two vessels. Most of its blood comes from the hepatic portal vein. The rest comes from the hepatic artery.
Understanding Cancer
Cancer is a group of many related diseases. All cancers begin in cells, the body's basic unit of life. Cells make up tissues, and tissues make up the organs of the body.
Normally, cells grow and divide to form new cells as the body needs them. When cells grow old and die, new cells take their place.
Sometimes, this orderly process goes wrong. New cells form when the body does not need them, or old cells do not die when they should. These extra cells can form a mass of tissue called a growth or tumor.
Tumors can be benign or malignant:
Benign tumors are not cancer. Usually, doctors can remove them. In most cases, benign tumors do not come back after they are removed. Cells from benign tumors do not spread to tissues around them or to other parts of the body. Most important, benign tumors are rarely a threat to life.
- Malignant tumors are cancer. They are generally more serious and may be life threatening. Cancer cells can invade and damage nearby tissues and organs. Also, cancer cells can break away from a malignant tumor and enter the bloodstream or the lymphatic system. That is how cancer cells spread from the original cancer (the primary tumor) to form new tumors (secondary tumors) in other organs. The spread of cancer is called metastasis. Different types of cancer tend to spread to different parts of the body.
Most primary liver cancers begin in hepatocytes (liver cells). This type of liver cancer is called hepatocellular carcinoma or malignant hepatoma.
Children may develop childhood hepatocellular carcinoma or hepatoblastoma. This site does not address childhood liver cancer.
When liver cancer spreads (metastasizes) outside the liver, the cancer cells tend to spread to nearby lymph nodes and to the bones and lungs. When this happens, the new tumor has the same kind of abnormal cells as the primary tumor in the liver. For example, if liver cancer spreads to the bones, the cancer cells in the bones are actually liver cancer cells. The disease is metastatic liver cancer, not bone cancer. It is treated as liver cancer, not bone cancer. Doctors sometimes call the new tumor "distant" disease.
Similarly, cancer that spreads to the liver from another part of the body is different from primary liver cancer. The cancer cells in the liver are like the cells in the original tumor. When cancer cells spread to the liver from another organ (such as the colon, lung, or breast), doctors may call the tumor in the liver a secondary tumor. In the United States, secondary tumors in the liver are far more common than primary tumors.