Day: May 21, 2012

How are Brain Tumors Classified?

Patient Presentation
A 10-year-old male came to the emergency room with double vision. Four weeks previously he was playing baseball and had a sudden attack of double vision. This stopped after a few minutes. The family saw an optometrist who changed his glasses’ prescription. The double vision then started to occur at other times, particularly with lateral gaze. He also had increased headaches, nausea and was tripping when walking. He was seen again by the optometrist and referred to the emergency room. The past medical history showed asthma and varicella. The family history was non-contributory. The review of systems revealed progressive headaches for 9 months.

The pertinent physical exam showed a well appearing male who was alert and oriented x 4. His heart rate was 99 and a blood pressure was 117/61 with other vital signs normal. Growth parameters were 25-50%. Eye examination revealed PERRLA, EOMI and lateral gaze evoked an increase in double vision. Fundascopic examination showed bilateral papilledema. Neurological examination showed normal strength and tone, DTRs were +2/+2, there was no truncal ataxia but difficultly walking because of his vision. The radiologic evaluation showed a right cerebellar cystic mass. The surgical pathology after complete excision revealed a diagnosis of a low-grade pilocytic astrocytoma.

Case Image

Figure 97 – Axial images from a CT scan of the brain performed without intravenous contrast demonstrates a heterogenous mass in the right cerebellum causing displacement of the slit-like fourth ventricle to the left (left image) and obstructive hydrocephalus with transependymal flow of cerebrospinal fluid (right image). The mass was felt to most likely represent a cerebellar astrocytoma.

Discussion
Primary brain tumors are a diverse group of tumors that together form the most common solid tumors in children. It is estimated that there are 2500-3500 children diagnosed each year in the U.S. with a brain tumor. Brain tumor causes remain unknown and the best treatment has not been determined. Overall 5-year survival is ~70% but the rates are diverse depending on the stage and tumor type. Multimodal treatment is often essential including neurosurgery, oncology, radiation oncology, neuroradiology, endocrinology, rehabilitation and psychology. Unfortunately many children may have long-term or late sequelae because of the treatment, particularly for younger children. Tumor recurrence is also not uncommon.

Some common ways that brain tumors present include: headache, nausea/emesis, ataxia including truncal, visual changes, clumsiness, back pain, subtle personality or performance changes, or found incidentally (e.g. found on imaging during head trauma evaluation).

A differential diagnosis of papilledema can be found here.

Learning Point
Brain tumors are classified according to location and histology and include:

  • Supratentorial
    • Astrocytomas
    • Atypical teratoid/rhabdoid tumor
    • Ependymomas
    • Gliomas
    • Oligodendrogliomas
    • Meningiomas
    • Neuronal and mixed neuronal glial tumors
    • PNETs (primary neuroectodermal tumors)
    • Choroid plexus tumors
    • Pineal region tumors
    • Metastasis from distant sites
  • Infratentorial or Posterior Fossa
    • Astrocytomas
    • Atypical teratoid/rhabdoid tumors
    • Ependymomas
    • Gliomas
    • Glioneuromas rosette-forming tumor of the 4th ventricle
    • Medulloblastomas
    • Choroid plexus tumors
  • Parasellar
    • Astrocytomas
    • Craniopharyngiomas
    • Germ cell tumors
  • Spinal cord
    • Astrocytomas
    • Ependymomas
    • Gangiliomas

Overall the most common pediatric brain tumor is medulloblastoma. It accounts for 40% of tumors in the posterior fossa and 10-20% overall.

Questions for Further Discussion
1. At what point does recurrent emesis or headache indicate the need for head imaging?
2. How should adult survivors of childhood cancers be followed?
3. What is the role of primary care providers in the treatment of childhood tumors?
4. What is the differential diagnosis of blurred or double vision?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Childhood Brain Tumors

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Kupfer GM, Arceci RM. Childhood Cancer Epidemiology. Medscape. Available from the Internet at http://emedicine.medscape.com/article/989841-overview#a1 (rev. 4/7/2011, cited 3/8/2012).

National Cancer Institute. General Information About Childhood Brain and Spinal Cord Tumors. Available from the Internet at http://www.cancer.gov/cancertopics/pdq/treatment/childbrain/healthprofessional (rev. 12/15/2011, cited 3/8/2012).

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    7. All medical and invasive procedures considered essential for the area of practice are competently performed.
    8. Health care services aimed at preventing health problems or maintaining health are provided.
    9. Patient-focused care is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

    Author

    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital