Any inflammation of the liver, whether caused by germs, drugs, or radiation, is called hepatitis . The liver is an astounding laboratory sustaining metabolism. Among it's functions are purification of the blood, removing poisonous ammonia from proteins, detoxifying alcohol and drugs, controlling the body's sugar and cholesterol balance, making bile to digest fats, forming clotting factors for the blood and generating new blood cells. This myriad of functions makes clear why the liver is essential to life. The cells in the liver are meant to divide to replace those that die of injury or old age.
Liver cancer starts within a single cell.
Something changes the control mechanisms within this cell, and it starts dividing in a disorganized, uncontrolled manner. They fail to perform the normal functions of liver cells, but are only intent on dividing to make more copies of themselves. Eventually these abnormal cells form a clump, or tumor. A tumor is merely a swelling, and isn't necessarily cancerous. By contrast, a malignant tumor is cancer and has a capacity to spread to any area of the body.