Cancer in Children Chapter 13 Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.

2 Childhood Cancers  Most common childhood cancers are leukemias, sarcomas, and embryonic tumors  Embryonic tumors Originate during uterine life Originate during uterine life Immature embryonic tissue unable to mature or differentiate into fully developed cells Immature embryonic tissue unable to mature or differentiate into fully developed cells Commonly named with the term “blast” Commonly named with the term “blast”

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 3 Cancer in Adolescents and Young Adults  2% of all invasive cancers  Malignancy rate in 15- to 29-year-olds is three times higher than that in children younger than 15 years  Most common cancers among 15- to 19-year-old population in the United States  Hodgkin lymphoma, germ cell tumors, central nervous system (CNS) tumors, non-Hodgkin lymphoma, thyroid cancer, malignant melanoma, and acute lymphocytic leukemia (ALL)  Many of the common malignancies in children younger than 5 years of age are virtually absent in 15- to 19-year-olds

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 4 Childhood Cancers  Most originate from the mesodermal germ layer  The mesodermal layer gives rise to connective tissue, bone, cartilage, muscle, blood, blood vessels, gonads, kidneys, and the lymphatic system

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 5 Childhood vs. Adult Cancers  <1% of cancers  Involves tissue  Nonepithelial and mesenchymal  Short latency  Ecogenetic involvement  Few prevention strategies  >99% of cancers  Involves organs  Carcinomas  Long latency period  Strong environmental and lifestyle influence  80% preventable

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 6 Childhood vs. Adult Cancers  Detection commonly accidental  80% have metastasized at time of diagnosis  Responsive to treatment  Long-term consequences with treatment  >70% cure  Screening linked to possible early detection  Cancers are local or regional at time of diagnosis  Less responsive to treatment  Fewer long-term consequences  <60% cure

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 7 Etiology  Multifactorial  Genetic  Environmental  Prenatal exposure  Childhood exposure

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 8 Etiology  Genetic factors  Oncogenes and tumor suppressor genes  Chromosome abnormalities Aneuploidy, amplifications, deletions, translocations, and fragility Aneuploidy, amplifications, deletions, translocations, and fragility  High recurrence risk

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 9 Etiology  Environmental factors  Prenatal exposure Drugs and ionizing radiation Drugs and ionizing radiation  Increased parental age  Childhood exposure Drugs, ionizing radiation, or viruses Drugs, ionizing radiation, or viruses  Anabolic androgenic steroids, cytotoxic agents, immunosuppressive agents, Epstein-Barr virus, and HIV

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 10 Prognosis  78% of children with cancer are now cured  Children more responsive and better able to tolerate treatments  More likely to be enrolled in clinical trials  Long-term effects of treatment  Psychologic ramifications