Brain Metastases

Most common sources of intracranial metastasis

• Lung cancer

• Breast cancer

• Skin cancer (melanoma)

• Kidney cancer

• GI tract cancer

10–15% of brain metastases are of unknown primary source

Most common metastatic carcinomas to the leptomeninges are breast, lymphomas, and leukemia

Intracranial metastases and primary cerebral neoplasms present similarly

• Intracranial pressure

• Focal or diffuse disturbance of cerebral function

Leptomeningeal metastases cause

• Multifocal neurologic deficits from infiltration of nerve roots

• Direct invasion of the brain or spinal cord

• Obstructive hydrocephalus

Laboratory and radiology studies are the same as for primary neoplasms

Lumbar puncture is needed only if carcinomatous meningitis is suspected

• Elevated cerebrospinal fluid pressure, pleocytosis, increased protein levels, and decreased glucose concentration are seen

• Malignant cells may be found on cytology

In leptomeningeal metastases, CT scans show contrast enhancement in the basal cisterns or hydrocephalus without any evidence of mass lesions

• Gadolinium-enhanced MRI often shows leptomeningeal involvement

• Myelography may show deposits on multiple nerve roots

A single cerebral metastasis may be irradiated, sometimes following surgical excision

Systemic immunotherapy may also be an acceptable initial option in select cases

Leptomeningeal metastases receive irradiation and intrathecal methotrexate

• Prognosis is poor, with an approximately 10% survival at 1 year

• Palliative care

For multiple cerebral metastases or widespread systemic disease,

• Stereotactic radiosurgery, whole-brain radiotherapy, or both, sometimes helps

• Systemic chemotherapy or immunotherapy may be options

• Otherwise, palliative care