1. 1 Cancer in Children Chapter 13

2. Mosby items and derived items © 2006 by Mosby, Inc. 2 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

3. Mosby items and derived items © 2006 by Mosby, Inc. 3 Childhood Cancers  Most common childhood cancers are leukemias, sarcomas, and embryonic tumors Embryonic tumors  Originate during uterine life  Immature embryonic tissue unable to mature or differentiate into fully developed cells  Commonly named with the term “blast”

4. Mosby items and derived items © 2006 by Mosby, Inc. 4 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

5. Mosby items and derived items © 2006 by Mosby, Inc. 5 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

6. Mosby items and derived items © 2006 by Mosby, Inc. 6 Etiology  Genetic factors Oncogenes and tumor-suppressor genes Chromosome abnormalities  Aneuploidy, amplifications, deletions, translocations, and fragility High recurrence risk

7. Mosby items and derived items © 2006 by Mosby, Inc. 7 Etiology  Environmental factors Prenatal exposure  Drugs and ionizing radiation Increased parental age Childhood exposure  Drugs, ionizing radiation, or viruses Anabolic androgenic steroids, cytotoxic agents, immunosuppressive agents, Epstein-Barr virus, and HIV

8. Mosby items and derived items © 2006 by Mosby, Inc. 8 Prognosis  78% of children with cancer are now cured  Children are more responsive and are better able to tolerate treatments  More likely to be enrolled in clinical trials  Long-term effects of treatment  Psychological ramifications