Metastatic brain tumors may be quite aggressive and may return even after surgery, radiation therapy, and chemotherapy.
Metastatic disease requires treatment of the original tumor site if applicable. Some primary brain tumors respond to certain forms of therapy better than others. Metastatic brain tumors are classified depending on the exact site of the tumor within the brain, type of tissue involved, original location of the tumor, and other factors.
Infrequently, a tumor can spread to the brain, yet the original site or location of the tumor is unknown. Metastatic brain tumors occur in about one-fourth of all cancers that metastasize (spread through the body). They are much more common than primary brain tumors .
Astrocytomas may also start here. Astrocytomas are generally subdivided into high-grade or low-grade tumors. High-grade astrocytomas are the most malignant of all brain tumors.
Ependymomas make up about 8-10% of pediatric brain tumors. The tumors are located in tiny passageways (ventricles) in the brain, and block the flow of cerebrospinal fluid (CSF). Ependymomas can be slow growing, compared to other brain tumors, but may recur after treatment is completed. Recurrence of ependymomas results in a more invasive tumor with more resistance to treatment.
Contrast dye is intravenously administered and the scanner starts taking a rapid succession of images this traces the path of blood flow into the brain and brain tumor. MRI Angiography (MRA) uses MRI scans to outline blood vessels in the brain by following blood flow. Angiography is used to plan the surgical removal of a tumor suspected to have a large blood supply or one located in a part of the brain with?dense blood vessels.
Contrast agent uptake, sometimes in characteristic patterns, can be demonstrated on either CT or MRI-scans in most malignant primary and metastatic brain tumors. This is due to the fact that these tumors disrupt the normal functioning of the blood-brain barrier and lead to an increase in its permeability.
Now neurological progression can be effectively controlled in most patients harboring a few intracranial metastases with aggressive focal treatment (surgery or radiosurgery) in combination with WBR.
WBR can be given immediately following focal treatment or at the time of recurrence. Control can be extended by frequent MR surveillance of the brain and radiosurgical treatment of new metastases months or years later. With control of intracranial disease, advances in cancer therapy will prolong survival, since most patients now succumb later to systemic, rather than intracranial disease.
Aggressive, focal treatment is only beneficial in patients with controlled or no systemic disease and independent health (Karnofsky Performance Score (KPS) 70). Age is also a determinant of outcome, with better outcomes in individuals less than 60 years old. |
