Malignant cancers strike certain organs, such as the colon or breast, more often than others. In an Opinion publishing August 9 in Trends in Cancer, researchers propose that this vulnerability in some organs may be due to natural selection. Humans can tolerate tumors in large or paired organs more easily than in small, critical organs, such as the heart, and so the larger organs may have evolved fewer mechanisms to defend against cancerous cells.
"The organs that are the most important to keeping you alive and capable of reproduction, such as the heart, brain, or uterus, may enjoy a better protection against cancer, all other things being equal," says Frédéric Thomas, an evolutionary biologist at the Center for Ecological and Evolutionary Cancer Research in France. "We are not saying that this is the main factor to explain the different susceptibility of organs to cancer, but it is a…
