Cancer in children, called pediatric cancer, differs from adult cancer in several ways. Cancers common in adults, such as those that occur in the lungs, breasts, prostate, or colon do not usually occur in children. The common types of cancer that strike children include neuroblastoma, which arises in nervous tissue; retinoblastoma, which develops in the eyes; nephroblastoma, also called Wilm's tumor, which occurs in the kidneys; rhabdomyosarcoma, which arises from soft tissues; and osteogenic sarcoma and Ewing's sarcoma, which develop in the bones. These cancers are extremely rare in adults.

The emotional impact on the family and physical and emotional consequences to the child are important considerations in the treatment of pediatric cancer. Fortunately, many of these cancers and leukemias are highly curable, and many children survive to lead normal lives following treatment. However, the treatment of pediatric cancer may have long-term consequences for patients as they live out normal life spans. For example, radiation therapy and chemotherapy can actually cause secondary cancers, including leukemia, years after treatment has been completed. Other long-term consequences of cancer treatment may include stunted growth and infertility later in life.

Scientists have found that the cells of pediatric cancers often show specific genetic abnormalities. These abnormalities have given researchers a better understanding of the genetic difference between normal cells and cancer cells.