Brainstem gliomas are tumors that grow in the brainstem, which connects the lower part of the brain to the top of the spinal cord. At Columbia University Irving Medical Center/NewYork-Presbyterian Hospital, our neurosurgeons specialize in the diagnosis and treatment of brainstem gliomas. Standard treatment varies depending on individual circumstances, but may include surgical removal of the tumor, chemotherapy and/or radiation.
Although small, the brainstem controls functions critical for survival. Breathing, heart rate, digestion and muscular coordination are all managed by the brainstem. Any of these functions can be compromised by a brainstem glioma.
Brainstem gliomas are categorized as astrocytomas, which are a group of brain and spinal tumors that originate from astrocytes. Astrocytes are star-shaped glial cells—cells tasked with keeping the brain and spine in good health. All astrocytomas belong to a broader category of tumors called gliomas.
Depending on growth speed and aggressiveness, brainstem gliomas can be categorized as one of two types:
- A diffuse intrinsic pontine glioma (DIPG) grows very quickly and invades other areas in the brainstem.
- A focal glioma grows slowly and tends to stay in one area of the brainstem. The outlook for individuals with this type is better than for those with DIPG.
Most brainstem gliomas occur in children. About 10 to 20 percent of all brain tumors in children are brainstem gliomas.
Symptoms vary and depend on several factors, such as an individual’s age, tumor location and size. As a brainstem glioma grows and exerts pressure on brain tissue and other structures nearby, the following symptoms may arise:
- Loss of feeling in the face
- Worsening handwriting
- Weakness and ataxia
- Failure to thrive
As a brainstem glioma grows, it occupies more space in the rigid skull. Since the skull is unable to expand, intracranial pressure increases, which can lead to headache, vomiting, nausea and drowsiness. Headache resulting from brainstem glioma typically occurs in the morning upon waking and gets better throughout the day.
Individuals whose brainstem gliomas expand into the fourth ventricle may experience hydrocephalus. Hydrocephalus occurs because the tumor blocks the natural cycling of cerebrospinal fluid (CSF). Hydrocephalus in turn can lead to higher pressure inside the head.
A physician will record a patient’s medical history and conduct a physical examination to establish symptoms. Also, a neurological examination may be performed to evaluate whether the brain, spinal cord and nerves are working correctly.
If a physician suspects a brain tumor or other abnormality, imaging tests are typically ordered. The results of the imaging tests are used to provide a diagnosis.
Magnetic resonance imaging (MRI) is the preferred imaging procedure because it produces highly detailed pictures of the brain and soft tissue structures. Often, a substance called gadolinium is injected into the patient during MRI to refine the detail and better visualize the tumor.
Not all patients should undergo MRI, and sometimes MRI is not available. The alternative to MRI is computed tomography (CT) scan, which is an imaging test that produces pictures with fewer details than MRI. As with MRI, a dye can be used with CT scan to improve the detail of the image of the tumor.
A biopsy is typically not performed because the brainstem is a difficult area to access and the results rarely affect treatment decisions. If performed, the biopsy is most often taken during brain tumor surgery.
A lumbar puncture is sometimes suggested to provide a diagnosis. If a patient has high pressure inside the skull, lumbar puncture is usually avoided.
To date, the cause of brainstem gliomas is unclear.
Like most brain tumors, brainstem gliomas are not inherited. However, individuals who have certain inherited conditions, like neurofibromatosis type 1, are at heightened risk for developing a brainstem glioma.
Brainstem gliomas tend to occur in children and young adults, with about 75 percent of brainstem gliomas arising in people younger than 20 years old. In adults, these tumors are rare, but if they do occur, they tend to arise in people in their 40s.
Our neurosurgeons consider several factors when devising a treatment plan for patients with brainstem gliomas. A patient’s age, as well as the tumor location and tumor type, are all considered in order to choose the optimal treatment.
If a neurosurgeon suspects focal glioma, brain tumor surgery may be recommended. During brain tumor surgery, a neurosurgeon removes part of the skull, a technique called a craniotomy, and then removes as much of the tumor as safely possible. Unlike DIPGs, focal gliomas tend not to weave into neighboring tissue, making tumor removal more feasible. Because safe removal is not generally possible for DIPGs, brain tumor surgery is not generally recommended for patients with DIPGs.
After brain tumor surgery or when surgery is not an option, the preferred treatment is often radiation therapy. Chemotherapy may also be used.
To treat hydrocephalus, which often accompanies brainstem gliomas, a neurosurgeon can perform a ventriculostomy. A ventriculostomy is a procedure in which a neurosurgeon surgically inserts a catheter into one of the ventricles to drain excess fluid and restore normal pressure within the head.