Neoplastic lesions of the brain

  • By: Terri
  • Date: November 8, 2010
  • Time to read: 4 min.

*Read from printed notes – Ian Brown


Notes from


  • Brain tumors may originate from neural elements within the brain, or they may represent spread of distant cancers.
  • Primary brain tumors arise from CNS tissue
    • account for roughly half of all cases of intracranial neoplasms
    • The remainder of brain neoplasms are caused by metastatic lesions.
  • In adults, two thirds of primary brain tumors arise from
    • structures above the tentorium (supratentorial)
    • In children, two thirds of brain tumors arise from structures below the tentorium (infratentorial).
  • 95% of brain tumours
    • Gliomas
      • Low grade
        • Astrocytoma
          • common in young people
      • High grade
        • Anaplastic astrocytoma
        • Gliobastoma multiforme
    • metastases
    • meningioma
    • pituitary adenoma
    • acoustic neuroma
  • Classification by tumor cell type is irrelevant to the emergency physician because emergent treatment is the same regardless of the tumor type.

Neoplasms, brain. CT images of several tumor type...


  • Tumors of the brain produce neurologic manifestations through a number of mechanisms
  • Small, strategically located tumors may damage specific neural pathways traversing the brain
    • Tumors can invade, infiltrate, and supplant normal parenchymal tissue, disrupting normal function.
  • Because the brain dwells in the relatively restricted repository of the cranial vault, growth of intracranial tumors with accompanying edema may compress normal tissue and impair function
    • Space-ocupying lesion
    • May manifest vision problems, and headaches
  • Tumors proximal to the third and fourth ventricles
    • may obstruct the flow of cerebrospinal fluid
      • leading to hydrocephalus
  • In addition, tumors generate new blood vessels (ie, angiogenesis)
    • disrupting the normal blood-brain barrier
    • causing edema
  • The cumulative effects of tumor invasion, edema, and hydrocephalus may elevate the intracranial pressure (ICP)
    • impair cerebral perfusion
  • Intracranial compartmental rise in ICP may provoke shifting or herniation of tissue
    • under the falx cerebri
    • through the tentorium cerebelli OR
    • through the foramen magnum
  • Slow-growing tumors
    • particularly tumors expanding in the so-called silent areas of the brain
      • such as the frontal lobe
    • may be associated with a more insidious course
    • These tumors tend to be larger at detection
  • Most primary brain tumors do not metastasize
    • Of those neural element tumors that do
      • intraparenchymal metastasis generally precedes distant hematogenous dissemination via the arterial system
  • Metastatic brain tumors from non-CNS primary tumors may be the first sign of malignancy
    • or they may herald a relapse.
    • Nonetheless, the signs and symptoms of brain metastases simulate those of primary brain tumours



  • headache
  • altered mental status
    • memory loss and decreased alertness
      • suspect: frontal lobe tumour
    • depersonalization, emotional changes, and behavioral disturbances
      • Temporal lobe neoplasms
    • increased irritability, unsteadiness, ataxia, headache, vomiting, and progressive obtundation
      • paedetric posterior fossa tumour
  • ataxia
  • nausea & vomiting
  • weakness & gait disturbance
  • Sensory disturbance
    • vision
    • smell
    • hearing
      • intermittent (then progressive) hearing loss, disequilibrium, and tinnitus
        • acoustic neuroma
  • focal seizures, fixed visual changes, speech deficits, or focused sensory abnormalities
    • onset of symptoms usually is insidious, but an acute episode may occur with
      • bleeding into the tumor, or
      • when an intraventricular tumor suddenly occludes the third ventricle
    • seizures, hemiparesis, visual field cuts, speech difficulties, and intellectual disturbance.
      • Supratentorial tumors in children
  • Pituitary adenoma
    • Non-functional
      • when large enough can compress optic chiasma
      • causing vision problems
    • Hypersecretory
      • secrete prolactin
      • women
        • amenorrhea-galactorrhea syndrome
      • men
        • impotence

Physical examination

  • Increased Intracranial pressure
    • papillaedema
  • Diplopia
    • compression/displacement of 6th CN
      • at base of brain
  • Impaired upward gaze (Parinaud syndrome)
    • may occur with pineal tumours
  • Homonymous hemianopia
    • tumour of occipital lobe
  • Anosmia
    • frontal lobe tumours
  • Brainstem and cerebellar tumors
    • cranial nerve palsies
    • ataxia
    • incoordination
    • nystagmus
    • pyramidal signs
    • sensory deficits
  • Facial, cochlear, and vestibular CN dysfunction
    • run through the cerebellopontine angle
    • Vestibular nerve
      • acoustic neuroma

Imaging studies

  • CT
    • Intravenous contrast
      • for tumour idenfication
    • May appear
      • hypodense
      • isodense
      • hyperdense
  • MRI
    • helpful in identifying
      • tumours in posterior fossa
        • including acoustic neuroma
      • haemorrhagic lesions
  • Xray
    • tumour on sella turcica
      • pituitary tumour/adenoma
  • Lumbar puncture
    • not needed

  • Acute hemorrhage into a tumor
    • Brain neoplasms predisposed to hemorrhage include lung cancer, melanoma, and choriocarcinoma.
  • Lesions near the third ventricle can cause
    • paroxysmal symptoms of headache, syncope, or mental status change.
    • vomiting, ataxia, memory changes, visual disturbances, or personality change
      s may occur
  • Episodic increases in ICP
    • secondary to pressure arising from blockage of cerebrospinal fluid outflow
  • Sudden death
    • obstruction of outflow drainage from the third ventricle
  • Sudden increases in ICP
    • may lead to life-threatening brain herniation
    • shifts the brain parenchyma in the direction of least resistance:
      • caudally through the foramen magnum (posterior fossa tumors) or
      • transtentorial apertures.
  • Some pituitary tumors are hormonally active
    • acromegaly
    • galactorrhea


Prehospital Care

  • Supportive
  • Airway disturbance
    • breathing difficulty
  • Signs of pronounced elevation in ICP
  • Impairment of consciousness
    • May necessitate definitive airway control with endotracheal intubation
    • Hyperventilation.

Emergency Department Care
  • Corticosteroids
    • may dramatically reduce signs and symptoms related to cerebral edema
    • experience relief within the first few hours of steroid therapy
      • Dexamethasone
        • agent of choice
          • minimal salt-retaining properties
  • For patients with signs or symptoms of impending herniation and airway compromise
    • consider use of adjunctive medications for rapid sequence intubation
    • These might include lidocaine and medication for rapid-onset neuromuscular blockade, with precautions to diminish fasciculations
    • Induction agents, such as thiopental, may be used
    • After definitive control of the airway,
      • consider gentle hyperventilation
  • Mannitol
    • Hyperosmolar agent
    • Reduce ICP & cerebral oedema
      • creating an osmotic gradient across an intact blood-brain barrier
      • between cerebrospinal fluid in arachnoid space and blood plasma
    • May have rebound
      • Increases in ICP
      • makes its use problematic

Surgical intervention/Radiotherapy

    • Tumour resection/debulking
    • Installation of ventricular shunt
    • Placement of radioactive implants

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