73 - Congenital Malignant Disorders

Abstract

Malignant tumors in newborns require special approaches to diagnosis and treatment. The spectrum of malignancies in neonates differs from that in children and adolescents. Most neonatal malignancies are solid tumors, many of which are identified in utero by routine prenatal ultrasound. Neuroblastoma accounts for more than half of malignancies in infants younger than age 1 month. The response to treatment in neonates also differs from that in children and adolescents: acute lymphoblastic leukemia, which is curable in most children older than age 1, is curable in less than 25% of newborns. In contrast, neuroblastoma, which responds poorly to treatment in older children, often resolves spontaneously in newborns. The treatment of malignant diseases in neonates presents special challenges. Neonates and infants experience more frequent and more severe side effects and late effects from chemotherapy compared with older children, due to differences in drug metabolism in newborns and the sensitivity of rapidly growing normal tissues to chemotherapeutic agents and radiation. Neonates and infants face an increased possibility of late effects such as neurocognitive sequelae, growth disturbances, impaired reproductive capacity, and secondary malignancies. Despite treatment tailored specifically for infants, the mortality rates for infants with cancer exceed those for older children.