Cancer

Cancer is the term given to a wide range of diseases with the same mechanism, which is cells growing much too rapidly to be healthful for the body. Cells undergo a natural process of living and dying as they get too old and/or become damaged. Some form solid masses, resulting in tumors; others do not, like leukemia.

You may have heard the term benign and malignant tumors. This refers to their tendency to grow back or not, not necessarily whether they are “good” or not. Benign tumors do not regrow if removed, as where malignant cancer does. But benign cancers in the brain are almost always dangerous.

There is much still to be understood about cancer, but we are pretty sure that it is caused by certain, increased genetic changes in cells that develop in cancer, though it is hard to say how much of the genetic changes are causal and how much is a result of the cancer.