Astrocytoma of the Brain
THE BRAIN IS COMPOSED MOSTLY of glial cells. Astrocytes are a type of glial cell described as star shaped with tentacle-like extensions that exist in the cerebral hemispheres and in the spinal cord. If astrocytes begin to excessively grow, they can form into a tumor called an astrocytoma. Of the 140 types of brain tumors, an astrocytoma is the most common brain tumor that originates in the brain. Based on the level of complexity plus the likelihood to cure a patient from the disease, astrocytomas are categorized into four Grades:
Grade I: Benign and curable with surgical resection. Grade I astrocytomas include Pilocytic Astrocytomas.
Grade II: Considered low grade because patients can be successfully managed long-term, but it requires close monitoring because this Grade of astrocytomas can transform into high-grade tumors.
Grade III (Anaplastic): When astrocytes lose their shape or function and have become malignant or cancer cells. Grade III is a cancerous grade of astrocytoma requiring immediate removal because of its propensity to grow and spread to other cells.
Grade IV (Glioblastoma Multiforme): Cancerous cells that are extremely aggressive and have formed more than one glial cell tumor in multiple locations within the brain. This condition requires expeditious treatment.
There are a wide range of effective surgical and non-surgical therapies available for the treatment of astrocytomas. Surgery would be performed by a neurosurgeon. A neuro-oncology expert, called a neuro-oncologist, will determine whether any chemotherapy or radiation therapy is necessary. Centers for Neurosurgery, Spine, and Orthopedics (CNSO) is NJ’s only comprehensive facility that can provide the assessment, treatment, rehabilitation, and compassionate care for brain tumor and spine tumor patients.
Symptoms of an astrocytoma are nonspecific and often overlap with a variety of other brain conditions. Depending on the location of the astrocytoma, symptoms may include:
- Morning headaches which progressively worsen
- Personality changes
- Altered mental status
- Nausea and vomiting
- Vision changes
- Speech difficulties
- Loss of balance and gait instability (ataxia)
These symptoms could be indicators of other medical conditions such as migraine, stroke, encephalopathy, meningitis, Alzheimer’s, or trauma. Evaluation by a specialist is required to make a proper diagnosis.
Causes & Risk Factors
In general, tumors grow from normal cells in the body that have incurred changes to their DNA causing them to excessively proliferate. These cells no longer grow and divide in an orderly fashion. The resulting mass of cells are benign tumors that can exert pressure on nearby organs and structures. For a benign tumor, Grade I, to become cancerous (malignant), additional DNA changes must occur that cause these cells to rapidly reproduce and invade adjacent organs and bones. Once cancer cells enter into either the bloodstream or lymphatic system, they can travel to distant sites within the body (metastasize) and grow additional tumors in other organs.
Several risk factors are associated with cancerous tumor growth:
- Age: Aggressive brain tumors are more common in adults over 35 years old, while slow-growing astrocytomas are more common in children and young adults.
- Radiation exposure: Ionizing radiation exposure is a significant risk factor for the development of a brain tumor. Ionizing radiation exposure can occur from nuclear waste or contamination, if no protective covering is used during radiation treatments for cancers and not wearing lead protection during multiple radiologic imaging studies. Currently there is no evidence linking electromagnetic radiation from electrical power lines or microwaves to the development of brain cancer.
- Family history/genetic factors: A familial history of a glioma-type brain cancer is a risk factor for brain cancer. Among other genetic conditions, neurofibromatosis type-1 was associated with slightly higher incidences of low-grade astrocytomas, such as a Pilocytic Astrocytoma. Subependymal Giant Cell Astrocytomas are associated with a genetic condition called tuberous sclerosis.
- Tuberous Sclerosis syndrome and Li-Fraumeni syndrome are both medical conditions in which patients grow multiple primary tumors within different organs. Both conditions are known to include the growth of brain tumors.
Because symptoms of a brain tumor can be vague and nonspecific, a detailed history needs to be taken regarding the nature and duration of symptoms, factors that make symptoms better or worse, and associated factors such as weakness, numbness, or seizures. This will be followed by a comprehensive neurological exam that looks for deficits. If upon conclusion of the physical examination the neurosurgeon detects a cause for concern, an MRI of the brain or spine would be ordered to confirm or rule out a brain tumor or other neurologic disorder under consideration.
The MRI is the preferred type of imaging for any type of brain disorder, including a brain tumor. MRIs provide the greatest visual details of the brain structures. Tumors are visible as enhanced masses and contrast can help further delineate contrast enhancing tumors. If an MRI cannot be performed, a CAT (computer tomography) scan with contrast or PET (position emission tomography) scan can be performed instead.
Brain tumors have a characteristic appearance on MRI or CAT scans, but the type of brain tumor cannot always be determined. It is critical to know the type of brain tumor because the type of treatment will depend on the origins of the tumor cells. Studies have shown, certain types of brain tumors resolve more efficiently and effectively with only surgical removal whereas other tumors require certain types of chemotherapy or radiation therapy or both. Depending on the type of tumor, its surgical removal may be necessary either before or after these types of therapy. In order to develop an exact treatment plan, a firm diagnosis must be made by a neurosurgeon performing a stereotaxic biopsy of the tumor. This is a minor surgical procedure that uses image guided computer navigation to place a biopsy needle exactly within the tumor and secure a core samples for histologic analysis.
Tissue collected during the biopsy is sent to the laboratory for evaluation under a microscope by the pathologist. Microscopic analysis will show whether the tumor is benign (non-cancerous) or malignant (cancerous), what type of cells it derives from, and the grade of the tumor. This information will allow the CNSO team to formulate a treatment plan.
Treatment options for an astrocytoma depends on the location, size, grade of the tumor, age, overall health, and past medical history.
Initial treatment may include a prescription of steroid medications to reduce swelling around the tumor, and to decrease pressure on nearby structures. Anti-seizure medications might also be prescribed.
After confirmed by a biopsy, low-grade tumors are often observed with serial imaging, especially if they are in delicate locations and are not causing any immediate symptoms.
For more easily accessible tumors, the preferred treatment is a surgical resection. Computer modeling is used to plan surgical trajectories and thereby minimize irritation to important neural network structures nearby. Other tools and techniques routinely used to maximize safety especially if the tumor is in a location that is hard to access include lasers, intraoperative MRI, and even awake surgery.
If part of the astrocytoma invades an important location of the brain, it may not be possible to safely remove that part of the tumor. In that case, some tumor material is left behind rather than risk brain damage and the associated loss of function of the patient. The smaller volume of the remaining tumor can then be treated via chemotherapy, radiation therapy, or other forms of treatment.
It is common to need addition treatment modalities in combination with surgical resection such as radiation therapy and chemotherapy.
Radiation Therapy (RT)
Usually follows the resection of a brain tumor, but sometimes it is used to first shrink the size of the tumor before the surgery. Radiation therapy is provided by a doctor who is a radiation oncology specialist trained in the use of a sophisticated machine that directs a beam of high-energy particles (x-rays or protons) at the tumor to shrink the tumor and eliminate just the cancer cells. Types of radiation therapy include:
- Image-Guiding Radiation Therapy and Intensity-Modulated Radiation Therapy – Use 3D brain CT images, CT scans, or x-rays taken before or during the treatment session to deliver beams of radiation at different intensities and angles to the tumor location.
- Proton Therapy, or Proton Beam Therapy, is used for tumors located near sensitive functional centers of the brain or large blood vessels. Protons release most of their energy within the tumor, leaving surrounding tissue relatively undamaged.
The machines that are used for delivering RT have different names, such as GammaKnife, CyberKnife, and LinAc (Linear Accelerator).
Radiation therapy can produce some side effects as well, such as: nausea, headaches, tiredness, loss of appetite, red, sore, inflamed skin, and other symptoms which are more specific to the location of the brain tumor.
Considered an adjuvant treatment for astrocytomas, which is commonly used together with radiation therapy to achieve better results and less side effects. Chemotherapy involves taking a medication, by mouth or IV, that targets tumor cells. Temozolomide (Temodar) is the most commonly used oral medication for astrocytoma. Side effects of chemotherapy can include nausea/vomiting/decreased appetite, fever, weakness, hair loss. The severity of effects usually depends on the dose and type of drug administered.
Tumor Treating Fields (TTF) Therapy
This type of therapy is used either together with chemotherapy or after radiation therapy and utilizes the electrical field to disrupt the growth of cancerous cells. During this treatment adhesive pads will be placed on the scalp, near the tumor location. While wearing a device called an Optune, an electrical field will then pass over the tumor area thereby reducing tumor growth.
Prognosis, Follow-up, and Rehabilitation
The most important factor for prognosis is the grade of the tumor grade. Low-grade tumors, such as pilocytic astrocytomas or diffuse astrocytomas have a good prognosis with a longer survival compared to higher grade, more aggressive tumors. CNSO neurosurgeons will discuss the prognosis as part of the ongoing treatment discussions. During treatment as well as after treatment, there will be the need for regular check-up appointments and routine scans to monitor the continued response to treatment. The frequency of the follow-up visits depends on the type of brain tumor and the grade of the tumor.
Depending on the area of the brain involved, occupational and physical therapy specialists may be included in the recovery process in order to secure a speedy return to daily activities.
Centers for Neurosurgery, Spine, & Orthopedics Can Help
The dedicated team at Centers for Neurosurgery, Spine, and Orthopedics (CNSO) understand how the diagnosis of an astrocytoma can drastically impact a person’s life. CNSO is structured with established board-certified neurosurgeons, rehabilitation specialists, physiatrists, and certified physical therapists, who always provide comprehensive coordinated care and treatment. CNSO offers multiple convenient locations for treatment spanning from Passaic County to Morris County and nearby towns including Clifton, Jersey City, and Parsippany, NJ. Northern NJ patients can learn more about brain surgery and brain tumor treatment options by contacting the doctors at CNSO today.