Cancer Chapter 162 Causes and Risks of Cancer A cancer is a cell that has lost its normal control mechanisms and thus has unregulated growth.
Cancer can develop from any tissue within any organ.
How Cancer Develops Cancer cells develop from normal cells in a complex process called transformation. The first step in the process is initiation, in which a change in the cell's genetic material primes the cell to become cancerous. However, not all cells are equally susceptible to carcinogens. A genetic flaw in the cell or another agent, called a promoter, may make it more susceptible. Even chronic physical irritation may make cells more susceptible to becoming cancerous.