What is Cancer? When people hear the word “cancer,” they typically think of some of the more common signs or symptoms of this family of diseases. Fewer, however, understand what cancer is or how it begins. To understand how cancer occurs, it is important to understand where it occurs: the human cell. Cells are actually quite miraculous in their own way. When we’re young, cells divide rapidly as part of our normal growth from infancy into adulthood. Once we’re adults, however, the functionality of healthy cells changes and cell division slows; only when a cell becomes too old, worn out or damaged to properly function does a new one replace it. Unfortunately, there are times when the cell mutates, or changes abnormally because its DNA becomes damaged. New cells begin to form and divide even when they are not necessary, and uncontrolled growth occurs. The damaged DNA is spread to the new cells. In some cases, these rapidly dividing cells form a mass or tumor. If the tumor is malignant, meaning cancerous, the cells can spread from one tissue or organ to another (metastisize)-something healthy cells don’t do. Other types of cancers, like leukemia, affect the blood and spread to other tissues as blood is pumped throughout the body. Regardless of how it spreads, however, each cancer requires a very specific type of treatment. Oncology is the medical science which focuses on the study, diagnosis and treatment of cancer. Through extensive education, research and trials, these specially trained physicians evaluate the best and most effective therapies to treat the many types of cancer which exist.