What are metastatic brain tumours?
Brain metastases are the most common forms of brain cancer, at a rate ten times higher than that of intrinsic primitive brain tumours. About 10% of patients diagnosed with systemic cancer develop brain metastases at the central nervous system . Lung cancer metastases are the most frequent, even with the growing frequency of breast cancer, however melanoma presents the greatest brain metastases frequency. 80% of metastasis is localized to the brain hemispheres, 15% to the cerebellar level, and 5% bone level.
What are the causes of brain metastases?
Brain metastases originate from the tumour cells born in other parts of the body, which have spread to multiple parts of the brain.
What are the symptoms of brain metastases?
The symptoms of brain metastases are similar to that of any cancer of the nervous system and consist of epileptic seizures, headache and neurological deficit.
Using a CT scan to examine the base head, and a basic brain MRI with contrast (gadolinium). Often patients with a suspected diagnosis of metastasis undergo a full body CT scan, with a contrast medium or using a body PET with an FDG purpose of staging systemic tumours.
The treatment of metastases depends on the number of metastases in the brain and control of the primary tumour at the systemic level. Surgery has the role to obtain a histological diagnosis of the disease and to remove metastases in case of accessible lesion with limited morbidity. In other cases it is performed using a needle biopsy (stereotactic) to obtain a histological diagnosis of the disease.
In patients with a controlled systemic tumour, in the case of metastases with only a small size (up to 3 cm), there exist no differences in the effect between radiosurgery and direct surgery on the metastases, when accessible by agreeable post-operative metastases. There is no difference in effect when radiosurgery is performed with an accelerator, or a Ciber knife/Gamma knife.
The surgery has a specific role in the case of large, symptomatic metastases, which are surrounded by a significant accessible edema. After surgery the standard is represented by the radiation of the whole brain, although recent studies have shown that the postponement of the WBRT does not change the overall survival of the patients, it is however associated with a faster rate of local or distant recurrence, but improves the overall cognitive performance of the patient. Post-surgery the performance of the focal radiotherapy improves the local control of the disease, and does not affect the cognitive performance of the patient.
In patients with controlled systemic tumours and various brain metastases (up to 3), the role of surgery in the case of patients with large metastasis that respond positively to the procedure, will notice a major mass effect (in patients with good general health). In all other cases, radiosurgery (radiation therapy) is recommended. In patients with more than three metastases and in non-controlled systemic diseases, radiation treatment on the whole brain is the standard procedure.