cancer
Development and Spread of Cancer
Initiation
The first step in cancer development is initiation, in which a change in a cell’s genetic material (a mutation) primes the cell to become cancerous. The change in the cell’s genetic material may occur spontaneously as a random event or due to a gene mutation or be brought on by an external exposure to a substance that causes cancer (a carcinogen). Some Carcinogens include many chemicals, tobacco, viruses, radiation, and sunlight. However, not all cells are equally susceptible to carcinogens. And not all people exposed to a carcinogen will develop cancer. The risk depends on many factors, for example, the amount of exposure the person had to that carcinogen or whether the person has a genetic predisposition to a certain type of cancer. 