Proliferation of cells that have managed to evade central endogenous control mechanisms is a hallmark of cancer. Cancers are classified not only by their organ or tissue of origin, but also by the molecular characteristics of the cancer cells themselves. Because of recent scientific advancements, it is now possible to examine the genetic structure of various cancer types in great detail in a limited amount of time, the growing body of information about cancer's development and progression can be used to develop more accurate diagnostics and/or less toxic cancer treatments. In the long run, the aim is to provide each cancer patient with a treatment regimen that is optimally adapted to his or her condition and circumstance.