Intracranial tumours (summary)

This is a basic article for medical students and other non-radiologists

Intracranial tumours comprise a heterogeneous group of tumours. In adult patients, the majority represent metastatic disease with a smaller proportion being primary brain tumours. Metastasis to the brain occurs, most commonly, from lung, breast, melanoma, renal cell, and colorectal cancers.

Reference article

This is a summary article; read more in our article on intracranial tumours.

Summary

• epidemiology

  • incidence increases with age

  • equivocal gender distribution

  • risk factors

    • malignancy elsewhere

• presentation

  • headache

  • features of raised intracranial pressure

    • nausea & vomiting worse in the morning or positional

  • altered mental state

  • focal neurology may occur as the tumour grows

  • adult-onset seizures

  • incidental finding

    • some tumours may not cause symptoms

    • patients may be imaged for another reason, e.g. trauma

• pathophysiology

  • heterogeneous group of tumours

    • metastases, e.g. lung, breast, renal

    • meningiomas

    • primary parenchymal tumours

    • pituitary or pineal tumours

    • cranial nerve schwannomas

  • tumours are graded using the WHO grade

• investigation

  • CT is often the first test performed to assess presenting symptoms

  • MRI may be used with symptoms of headaches or seizures

  • MRI is the investigation of choice to characterise the tumour

• treatment

  • parenchymal brain tumours generally have a poor prognosis

  • treatment should be in specialist centres

    • steroids may alleviate symptoms caused by oedema

    • antiseizure medications may help for those with seizures

    • a biopsy may be performed neurosurgically

    • some tumours may be removed, e.g. pituitary tumours

    • stereotactic radiotherapy can be used for small lesions

Imaging

• role of imaging

  • confirm intracranial abnormality and prioritise MRI

  • tumour characterisation

  • help to determine the grade, and make a decision about biopsy

  • follow up

• radiographic features

  • CT

    • often the first line test

    • variety of appearances depending on the tumour

    • hypo- or hyperdense, irregular, well-defined, peripheral or deep

    • useful to determine oedema and mass effect

    • contrast may make lesions more conspicuous

    • CT is especially helpful for determining bony involvement

  • MRI

    • investigation of choice

    • fantastic contrast and spatial resolution

    • origin of tumours can be determined

    • different sequences are used to determine the likely diagnosis

    • specialised sequences can be useful to look at tumour metabolites