What is cancer?

Cancer develops when cells in the body begin to grow out of control. Normal cells grow, divide, and die. Instead of dying, cancer cells continue to grow and form new abnormal cells. Cancer cells often travel to other body parts where they grow and replace normal tissue. This process, called metastasis, occurs as the cancer cells get into the bloodstream or lymph vessels. Cancer cells develop because of damage to DNA. DNA is in every cell and directs all its activities. When DNA becomes damaged the body is able to repair it. In cancer cells, the damage is not repaired. People can inherit damaged DNA, which accounts for inherited cancers. Many times, DNA becomes damaged by exposure to something in the environment, like smoking. (American Cancer Society, Learning about Cancer overview)

Types of Cancer

• Most common types: Breast, Prostate, Lung, Colon, Urinary Bladder, Non-Hodgkin Lymphoma, Melanomas of the Skin, Kidney, Pancreatic, Head and Neck, and Ovarian
• Less common types: Thyroid, Stomach, Brain, Multiple Myeloma, Esophagus, Liver, Cervix, Larynx, Acute Myeloid Leukemia, Chronic Lymphocytic Leukemia, Hodgkin Lymphoma, Testis, Intestine, Anus, Vulva, Gallbladder, Bones and Joints, Hypopharynx, Eye, Nose, Nasopharynx, Ureter, and Gastrointestinal Carcinoid Tumors.
• Childhood cancers: Leukemia (Acute Lymphoblastic Leukemia is the most common childhood cancer), cancers of the Central Nervous System, bone cancers, Hodgkin's Disease, non-Hodgkin Lymphoma, Liver cancer, Kidney cancer, and more.
  (Association of Cancer Online Resources, Types of Cancers)

Distribution of Cancer Types

Childhood Cancer Statistics

• Approximately 12,400 children under the age of 20 are diagnosed with cancer each year.
• About one in 300 boys and one in 333 girls will develop cancer before the age of 20.
• The incidence for cancer is greater among white children than for children in all other ethnic groups. The largest racial difference is for leukemia, where the rate for whites is 41.6 per million, and only 25.8 per million for blacks.
• Since the 1970s, deaths from childhood cancer have declined dramatically. The overall decline in mortality was nearly 40% between 1975 and 1995, about 2.5% per year decrease, even while the incidence increased by 0.8% per year.
• Cancer is the most common disease-related cause of death for ages one to twenty, and the fourth most common cause of all deaths, after accidents, homicides, and suicides.
  (CureSearch: National Childhood Cancer Foundation, Our Research)