Definition: Metastatic brain tumors arise from tumor cells that have traveled (metastasized) from other organs to the brain. All metastatic brain tumors are considered malignant based on the fact that they have spread from one organ to another. Metastatic brain tumors are assigned a grade according to the accepted grading system for the organ in which the tumor cells originated. The types of cancer that most commonly spread to the brain are lung, breast, skin, colon, and kidney cancer. Multiple metastatic brain tumors may be present.
Symptoms: The most common symptom of a metastatic brain tumor is a headache that slowly worsens over time. Other symptoms depend upon the location of the tumor or tumors.
Evaluation: Metastatic brain tumors are evaluated with MRI or CT scans. Additional imaging may be ordered to look for tumors in other parts of the body and to try to identify the source of the tumor. A lumbar puncture (spinal tap) may be performed if it is suspected that there are tumor cells in the cerebrospinal fluid.
- Surgery: Surgical biopsy of a metastatic brain tumor is recommended for diagnosis if there are no tumors in more easily accessible parts of the body. Maximal surgical removal of one or more metastatic tumors is performed if the tumors are accessible and causing symptoms.
- Radiation: Stereotactic radiosurgery can be delivered to smaller metastatic tumors. Fractionated whole brain radiation is often recommended if there are multiple metastatic tumors present.
- Chemotherapy: Chemotherapy is selected based on the source of the metastatic tumor and the presence of tumors in other parts of the body.
Follow-up: Long-term close follow-up with regular MRI scans is recommended to watch for the growth of new tumors or tumor recurrence requiring further treatment.