What is Cancer?

Cancer is the general name for a group of more than 200 diseases where cells in a part of the body begin to grow out of control. Although there are many kinds of cancer, they all start because abnormal cells grow out of control. Untreated cancers can cause serious illness and death.

Not all cancers are the same, even when they share a common name. Cancers can begin in many different parts of the body. Different types of cancer can act very differently. For example, lung cancer and breast cancer are very different diseases. They grow at different rates and respond to different treatments. That is why people with cancer need treatments that target their specific type of cancer. As research into the genetic and molecular make up of cancer cells advances, oncologists have an increasingly clearer view of how to personalize treatment plans for patients.