Which are the symptoms?
Symptoms are similar to those of primary central nervous system tumors and may include:
- headache, nausea, vomiting (symptoms of endocranial hypertension);
- focal neurological deficits;
- changes in mental state (e.g., depression, lethargy);
- symptoms of vascular disorders (transient ischemic attack, stroke) due to vessel compression by a neoplasm or bleeding.
How is it diagnosed?
Diagnostic examinations include computed tomography (CT) and, above all, magnetic resonance imaging (MRI) of the brain with gadolinium, which can accurately assess even the number of lesions.
Tumor staging studies, particularly whole-body CT scans, are also necessary.
How is it treated?
The optimal treatment is determined by the neurosurgeon in conjunction with the oncologist and can be surgical, radiotherapy, and radiosurgery.
A multicenter study has shown that radiosurgery achieves 85% local disease control with low morbidity: therefore, radiosurgical treatment with the Gamma Knife (which allows high doses of gamma rays to be injected even into very small lesion with extreme precision while preserving surrounding brain structures) is offered both to patients with a single lesion as an alternative to surgery, and to patients with multiple lesions as a replacement or together with fractional whole-brain radiation therapy.
It should be noted that the treatment of brain metastases is only one step in the treatment plan for a cancer patient. For this reason, the indication to use Gamma Knife is given by the neurosurgeon in collaboration with the oncologist who evaluates the systemic disease; this requires recent staging studies (usually whole-body computed tomography and bone scintigraphy), in addition to histological examination of the primary tumor.
Surgical intervention is indicated in individual cases, such as when there is a single metastasis from an unknown primary tumor or when there is a bulk lesion with mass effect causing neurologic deficits.