Neuro-oncology

Classification

• primary vs. metastatic, intra-axial (parenchymal) vs. extra-axial, supratentorial vs. infratentorial, adult vs. pediatric

• benign: non-invasive, devastating due to expansion of mass in fixed volume of skull (mass effect)

• malignant: implies rapid growth, invasiveness, but rarely extracranial metastasis

• types of intracranial tumours (* = most common)

  • neuroepithelial tissue

    • astrocytic tumours: astrocytoma, glioblastoma

    • oligodendroglial tumours

    • oligoastrocytic tumours

    • neuronal and mixed neuronal-glial tumours: ganglion cell tumours, cerebral neurocytomas/neuroblastomas

    • embryonal tumours: medulloblastoma, neuroectodermal

    • other: pineal, ependymal, and choroid plexus tumours

  • meningeal: meningiomas*, mesenchymal, hemangioblastomas

  • cranial and paraspinal nerves: schwannoma, neurofibroma

  • lymphomas and hematopoietic neoplasms

  • germ cell: germinomas, teratomas

  • pituitary adenomas*

  • sellar region: craniopharyngiomas, spindle cell oncocytoma

  • cysts: epidermoid/dermoid cysts, colloid cysts

  • local extension: chordomas, glomus jugulare tumours

  • metastatic tumours

Clinical Features

• progressive neurological deficit (70%): usually motor weakness, ± CN deficits, sensory, cognitive, personality, endocrine deficits (these may localize lesion)

• H/A (50%) ± symptoms of elevated ICP

• N/V (40%)

• seizures (25%)

• papilledema, vision changes

• symptoms suggestive of TIA (ictal, post-ictal, or ischemic 2° to "steal phenomenon")

• rarely presents with hemorrhage

• familial syndromes associated with CNS tumours

  • von Hippel-Lindau (hemangioma)

  • tuberous sclerosis (astrocytoma)

  • neuro fibromatosis type 1 and 2 (astrocytoma, acoustic neuroma respectively)

  • Li-Fraumeni (astrocytoma)

  • Turcot syndrome (glioblastoma multiforme)

  • multiple endocrine neoplasia type 1 (MEN-1) (pituitary adenoma)

Investigations

• CT, MRI, stereotactic biopsy (tissue diagnosis), metastatic work-up