Top Cancer Surgeons in Delhi, India. Cancer is eventually the outcome of cells that uncontrollably grow and do not die. Normal cells in the body follow an order for growth, division, and death. Human cells grow and divide to form new cells as the body needs them. Normally, cells grow old or become damaged, they die and new cells take their place. In every kind of cancer, some of the body’s cells begin to divide without stopping and spread into nearby tissues. Cancer cells differ from normal cells in many ways that allow them to grow out of control and become aggressive. Cancer cells are able to ignore signals that normally communicate cells to stop dividing further. Cancer cells do not understand how to function whereas normal cells mature into individual cell types with specific functions.