Pediatric Tumors

Cancer remains to be the most common cause of death in pediatric population second to the accidents in all death causes between birth and 14 years of age. Leukemias and central nervous system (CNS) tumors together constitutes more than half of childhood cancers followed by lymphomas, soft tissue sarcomas half of which are rhabdomyosarcomas, neuroblastoma, and Wilms’ tumor for children aged 1–14 years. Solid CNS tumors and lymphomas are the most common cancers in 15- to 19-year-olds with other relatively less common tumors of leukemia, thyroid carcinoma, testicular germ cell tumors, soft tissue sarcomas, bone tumors, and melanoma. Due to the contemporary therapies, long-term disease control and 5-year survival have increased in pediatric population albeit childhood cancer survivors have treatment-related physical and functional limitations compromising the quality of life. However, lowered therapeutic exposure strategies, particularly rate of radiotherapy administration reductions, have lowered late effect rates in more recent decades. Basic concepts that are crucial to understanding pediatric tumors are reviewed in depth in this chapter.