🧠 Tumours of the Central Nervous System

🧠 Tumours of the Central Nervous System

August 6, 2024
Core, Neurosurgery, Oncology
Metastasis, Radiotherapy

Tumours of the Central Nervous System #

mindmap
  root((Brain Tumors))
    CNS Tumors  
        Brain - MC
        Spinal
    Types
        1ry Tumors
            Glioma
                MC Operated
                60yr
            Meningioma
                MC Tumor
                1/4 Symptomatic
                NF-2 
 Irradiation
        2ry/Mets
            Breast
            Renal
            Melanoma
            Colorectal
    CFx - Nonspecific
        Hx
            Headache - MC
            Memory loss
            Personality change
            Dysphagia
            Weakness
            Fits
        Low index of 
 suspicion.

Introduction #

  • The prognosis for a brain tumour diagnosis remains poor.
  • The three most common brain tumours are
    • meningiomas - Most common brain tumor
    • Glioma is the most commonly operated brain tumour.
    • and cerebral metastases.
  • For patients diagnosed with brain tumours, surgery is rarely curative.
  • Surgery may be offered to
    • aid control of tumour growth,
    • alleviate patient symptoms,
    • or control raised intracranial pressure.

Classification of CNS Tumours #

  • Most central nervous system tumours occur in the brain.
  • Tumours may be primary or secondary (metastatic).

Primary Tumours #

  • Glioma and meningioma are the most common.

Secondary Tumours #

  • Common primary sites that metastasize to the brain include breast, renal, melanoma, and colorectal tumours.

Clinical feature #

  • Symptoms can be non-specific, including
    • personality changes,
    • memory loss,
    • headache
    • weakness,
    • dysphasia, and
    • seizures.

[!warning]

  • Delay in diagnosis: Brain tumour patients typically see their GP five times before diagnosis.

Imaging #

MRI Brain #

  • Consider MRI in any patient with progressive, sub-acute loss of central neurological function.
  • CT scans are adequate for immediate needs
  • but MRI provides more detail, especially with intravenous contrast.

Imaging Characteristics #

  • Glioblastomas (GBMs):
    • Enhance heterogeneously with contrast,
    • usually localized to a single focus.
  • Meningiomas:
    • Located adjacent to cerebral meninges,
    • often showing a CSF cleft and homogenous enhancement with contrast.
  • Metastases:
    • Multiple foci in discrete brain regions,
    • often at the grey-white matter junction.

Management #

  • Brain imaging predicts tumour type, but histological examination confirms the diagnosis.
  • Surgical approaches aim for tumour debulking rather than just biopsy.

Primary brain tumors #

Gliomas #

  • Most commonly operated brain tumor.
  • Glioblastoma is the most common.
  • Peak age 60yr.
  • Treatment includes
    • Surgical resection followed by radiotherapy and temozolomide.

Meningiomas #

  • Most common primary brain tumour, often found incidentally.
  • Arise from arachnoid cap cells of the dural meninges.
  • Risk factors
    • Previous cranial irradiation and
    • neurofibromatosis type 2.
  • Only a quarter (1/4) of patients are symptomatic at presentation.
  • Incidental lesions are
    • small,
    • located adjacent to non-eloquent brain, and
    • heavily calcified.

Secondary Brain Tumours #

  • Commonly metastasize from
    • breast,
    • renal,
    • melanoma, and
    • colorectal primaries.
  • Surgery is considered if systemic disease is controlled and there is a single symptomatic lesion.