Neuroblastoma

Neuroblastoma is a common childhood neoplasm and is the most common extracranial solid tumor in children

Epidemiology

• Prevalence – 600 new tumors yearly in the U.S.
• Age – median is 2 years
• Sex – slightly higher female predominance
• Occurrence - mostly sporadic, 1-2% are familial

Risk Factors 

• Neurofibromatosis
• Nesidioblastosis
• Hirschsprung disease

Pathophysiology

• Malignant tumor consisting of poorly differentiated ectodermal cells derived from the neural crest

Clinical Presentation

• Determined by tumor location and stage
• Localized tumors are often asymptomatic (25-40% of patients)
• Metastatic tumors frequently associated with fever, bone pain and weight loss
  • Orbital metastases – ecchymoses called raccoon eyes
  • Paraspinal disease – paresis and cord compression
  • Cervical, apical thoracic disease – Horner syndrome
• Paraneoplastic syndromes
  • Opsoclonus-myoclonus syndrome (dancing eyes, dancing feet)
    • Involuntary eye fluttering
    • Muscle jerking
    • Ataxia
  • Vasoactive intestinal polypeptide – refractory diarrhea, failure to thrive

Diagnosis

• Laboratory testing
  • Increased urinary vanillylmandelic acid and homovanillic acid
  • Characteristic histology on tissue specimens
  • Use criteria of International Neuroblastoma Staging System (INSS)
• Staging
  • Bone marrow biopsy
  • CT scan
  • Metaiodobenzylguanidine scan (MIBG)

Disease Monitoring  

• Markers
  • N-myc amplification – amplification associated with poor prognosis
  • DNA index – aneuploidy associated with poor prognosis
  • Others – not used in initial risk staging
    • Neuron specific enolase
    • Ferritin
    • Chromosome additions/deletions – 17a, 1p36
    • TrKA and B
  • Screening the general population is not recommended

Prognosis

• Age, stage and marker related
• Younger patients do better; spontaneous regression occurs in 10%

Indications for Ordering

• Tests generally appear in the order most useful for common clinical situations
• Click on number for test-specific information in the ARUP Laboratory Test Directory

• Click on number for test-specific information in the ARUP Laboratory Test Directory