A quarter of cancers diagnosed in those under 18 years of age are leukemias, another quarter being tumors of the central nervous system. The remaining cancers are solid tumors occurring elswehere in the body, most commonly lymphomas, soft tissue and bone sarcomas, neuroblastomas and Wilms tumors. In almost all cases, the treatment of these solid tumors consists of combinations of surgery, cytotoxic drugs and radiotherapy. Although the prognoses have improved, they exhibit variation even within tumor groups. New targeted therapies are being developed, but for the time being they do not have any significant role.