Benign tumors do not spread in this way. The nucleus, which houses the chromosomes, is the control center for the cell. The nucleus of a normal cell such as a muscle cell, controls its activity as part of a larger tissue, a muscle. The cell will then act in concert with other cells of that muscle to expand and contract causing motion. Damage to the nucleus causes the cell to lose the ability to behave normally.
Cancer occurs when the damage causes changes that make the cell grow and divide uncontrollably.
When a cell become cancerous, a tumor eventually forms from these abnormal cells. Because the tumor is made up of defective cells, it cannot serve the function of the tissue from which it arose. The body suffers from both the loss of the normal function of that tissue as well as the damage to other tissues. For example, when a cancer replaces the liver tissue , the body cannot filter wastes properly. A cancer is named according to the type of organ tissue from which it developed.