Sugar Land - Visiting Nurse Assn . It is the nature of cells to divide and increase their number in a process called mitosis. Normal cells divide to replace those lost, or to repair injuries only, then stop dividing.
Cancer is an abnormal, continuous multiplying of cells.
The cells divide uncontrollably and may grow into adjacent tissue or spread to distant parts of the body. The accumulation of tumor cells eventually become large enough to produce lumps, masses, or tumors that can be detected. Cancers cause problems because they grow and occupy space, sometimes pushing on other structures and causing them to malfunction. They may also erode into other structures and bleed. Cancers have no nerves so they do not hurt, but they can cause other structures to hurt because of the destruction or pressure on the normal structures.