What is Metastatic Lung Cancer to the Brain?
When lung cancer spreads or metastasizes to the brain it is important for the patient to be aware of all treatment options in addition to the risks and benefits of each. Treatment options generally include radiation therapy, radiosurgery, surgery, or a combination of these treatments. Steroids are often administered to help relieve swelling caused by these brain tumors. Certain factors including the number, size, and location of metastatic brain tumors are taken into consideration when choosing the most appropriate treatment option(s).
Common Treatments for Metastatic Lung Cancer to the Brain
At the JD Lipani Radiosurgery Institute, we provide treatments for lung cancer that spreads to the brain and/or spine in the NJ area. Common treatment options include surgery, steroid therapy, radiation therapy, and radiosurgery.
Click on a treatment to learn more about it.
Surgery for Metastatic Lung Cancer to the Brain
Surgery for metastatic lung tumors to the brain is performed by a neurosurgeon (AKA brain surgeon). Brain surgery is performed under general anesthesia to remove the mass lesion or tumor from the brain. Surgery is recommended when a tumor within the brain compresses the surrounding brain tissue and requires expedient decompression or debulking to avoid a potentially life threatening situation.
Once the tumor is removed, the pressure on the brain is relieved and the patient begins the recuperation process. Problems arise if the tumor is within a critical location that is vital for performing a particular function such as motor, sensory, visual, consciousness etc. Sometimes brain tumors irreversibly damage critical brain tissue which can prevent recuperation of lost neurological function. Furthermore, some tumors are located in inaccessible areas and such tumors are thus classified as “inoperable”. Inoperable brain tumors are located in areas that cannot be accessed by the surgeon without causing serious injury to structures en route to or within the tumor location.
Steroid Treatment for Metastatic Lung Cancer to the Brain
In addition to compressing local brain structures, metastatic brain tumors also tend to swell and the swelling can also cause pressure or mass effect on surrounding brain tissue. Pressure on brain tissue can result in loss of brain function. For example, pressure on the motor cortex can result in weakness affecting the arm, leg, or both. Pressure on the speech center can result in unclear or unintelligible speech.
Often, steroids are administered orally or intravenously to reduce the swelling caused by brain tumors. Steroids can help relieve neurologic symptoms caused by swelling temporarily. Steroids do not inhibit tumor growth and therefore are often used as a temporary measure to relieve symptoms until more definitive treatment is delivered.
Radiation Therapy Treatment for Metastatic Lung Cancer to the Brain
Radiation therapy treatment for metastatic brain tumors is commonly delivered as whole brain radiation therapy or focused external beam radiation therapy. The distinguishing feature of these forms of treatment is that radiation is directed to affected brain regions or the whole brain as opposed to discrete targets revealed on radiographic images. The concept is to incorporate regions of the brain that are believed to contain microscopic or undetectable cancer cells and to prevent them from growing into large space occupying tumors.
This treatment option is considered when there is evidence of multiple lesions (4 or more) on imaging studies or when an aggressive cancer type is present. Radiation therapy delivered to the brain has certain risks related to radiation effects on normal brain tissue. Some side effects include memory impairment, difficulty concentrating, personality changes, and psycho-motor slowing. Therefore, careful judgment should be used to defer such treatment until which time it becomes absolutely necessary. An alternative to radiation therapy is radiosurgery, a technique used to treat discrete targets while minimizing radiation exposure to healthy brain tissue. Frequent post treatment monitoring with MRI scans is used to detect evidence of additional tumors that can be treated before significant growth has occurred.
Radiosurgery Treatment for Metastatic Lung Cancer to the Brain
Radiosurgery is used to deliver high dose radiation to discrete targets within the brain while minimizing radiation exposure to healthy brain tissue. Like radiation therapy, radiosurgery is non-invasive, meaning there is no cutting into the brain or skull, no pain, and no anesthesia. Radiosurgery for metastatic brain tumors is commonly performed using CyberKnife or Gamma Knife by highly qualified and specially trained radiation oncologists and neurosurgeons. The words “knife” and “surgery” may be misleading when describing radiosurgery but they are used to denote the precise tumor-killing power of this technology that is compared to that of a surgeon’s scalpel. Radiosurgery can often be used as an alternative to traditional open brain surgery and can also be used to treat brain tumors that are considered inoperable.
Other indications for radiosurgery include treatment to the postoperative resection cavity that targets microscopic cells or small residual tumors left behind after surgery. A clear distinction between radiosurgery and open brain surgery is that radiosurgery cannot physically remove a mass from the brain. Instead, the tumor cells are destroyed and the tumor usually shrinks over time. In some cases however, expedient open surgery must be pursued in an effort to relieve significant life threatening pressure on the brain. Radiosurgery for metastatic brain tumors is not indicated for tumors that require emergent debulking or decompression or for tumors that are deemed too large for radiosurgery. However, as technology, training, and expertise advance, the application of radiosurgery as a valuable treatment option is becoming more common.
Gamma Knife Treatment for Metastatic Lung Cancer to the Brain
Gamma knife radiosurgery is a non-invasive procedure that uses a number of converging radiation beams that are designed to deliver a high level of radiation to a very small and precise target. The patient’s head is fixed to a stereotactic frame which is attached to the treatment table for targeting purposes. Treatment is delivered in a single session or treatment fraction.
CyberKnife Treatment for Metastatic Lung Cancer to the Brain
The CyberKnife system utilizes a LINAC (linear accelerator) attached to a robotic arm that delivers several precise radiation beams to the target. Rigid head fixation is not required as in Gamma Knife. The CyberKnife also utilizes hypofractionation (i.e., treatment delivered over 2-5 consecutive days) that can be used to further protect healthy tissue from radiation damage. Both Gamma Knife and CyberKnife are performed as an outpatient treatment.