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In the United States, the number of people diagnosed with liver cancer is fairly low as compared with the rest of the world. A person’s lifetime risk of getting liver cancer in the U.S is about 1 in 132.
In 2010, the National Cancer Institute (NCI) reported 24,120 new liver cancer cases. Of those, 18,910 people are estimated to die from the disease. In sub-Saharan Africa, Southeast Asia and other parts of the world, liver cancer is the most commonly diagnosed type of cancer.
The annual global death rate for liver cancer is more than 700,000, according to the World Health Organization.
To understand what liver cancer is, it is important to first understand how the liver — the largest organ inside the human body — functions, and what it does to sustain life.
The liver is a pyramid-shaped organ that lies underneath your right ribs, just below the right lung. It is divided into right and left lobes and is uniquely fed blood from two sources.
The hepatic artery pumps in oxygen-rich blood and the portal vein pushes nutrient-rich blood absorbed from the intestines to the liver where it is broken down and stored.
In addition, the liver is responsible for making clotting factors needed to stop bleeding from a cut or injury and it breaks down toxic wastes in the blood and removes them from the body. For these reasons and others, it is impossible to live without your liver.
With so many jobs to do, it is easy to understand why the liver is made up of so many different kinds of cells. But with such an array of cells available, the liver has ample opportunity for a variety of tumors to form. Some of these tumors can be cancerous and some are not.
When a cancerous tumor develops in the liver, it is called a primary tumor. If the tumor cells break off and form elsewhere in the body it is called secondary tumor. For example, if liver cancer cells breaks off and spreads to the intestines, it is treated as metastatic liver cancer, not as intestinal cancer.
Hepatocellular carcinoma (HCC) is the most common form (about 75 percent) of liver cancer in adults, according to the American Cancer Society (ACS).