Zurak Cancer Foundation

Childhood Cancer - Overview Cancer is uncommon in children. Most cancers (99%) develop in adults, and it is most common in older adults. About one out of every six adults will develop cancer during his or her lifetime, while one in 300 boys and one in 333 girls will develop cancer before the age of 20. At the same time, there is a lot of research going on to discover new treatments for childhood cancer. This ongoing research has greatly improved the overall survival rate for children with cancer, which is now more than 80%. What is childhood cancer? Cancer begins when normal cells change and grow uncontrollably. In most types of cancer, these cells form a mass called a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can spread to other parts of the body. A benign tumor means the tumor will not spread. In leukemia, a cancer of the blood that starts in the bone marrow, these abnormal cells very rarely form a solid tumor. Instead these cells