Brenda Spriggs, MD, MPH, MBA
The brain contains three main parts: the forebrain, the midbrain and the hindbrain. The cerebrum is the largest part of the brain. Located in the forebrain, it is divided into the frontal lobe, parietal lobe, occipital lobe and temporal lobe. The frontal lobe is responsible for reasoning, planning, parts of speech, movement, emotions and problem solving. Abnormal growth of cells can cause brain tumors to develop anywhere in the brain. Glioma is one type of brain tumor that can affect the frontal lobe.
A glioma brain tumor originates in the glial cells of the brain. The glial cells make up the supportive tissues of the brain and do not contain nerves. Glioma tumors may be either benign or malignant. Benign tumors contain distinct borders and consist of harmless cells. Malignant tumors contain harmful cells that invade healthy cells and spread to other locations. In the brain, doctors also classify tumors that contain harmless cells but reside in a vital area of the brain as malignant.
Glioma is a general term used to describe any non-nerve cell in the brain. Because different types of glial cells exist, doctors must classify the tumor based on the specific type of cell involved. Astrocytoma tumors begin in the astrocyte cells. Ependymoma, which account for approximately 9 percent of all glioma, begin in the ependymal cells that line the ventricles and the spinal canal, according to Massachusetts General Hospital. Oligodendroglioma, which commonly occurs in one of the cerebral hemispheres, usually grow slowly and often contain other types of glial cells.
The symptoms of a brain tumor vary depending on the portion of the brain affected. Because the frontal lobe controls voluntary muscle movements, according to Massachusetts General Hospital, a glioma of the frontal lobe may cause an interference with muscle coordination and lead to one-sided paralysis known as hemoplegia. Other symptoms of a frontal lobe tumor include seizures, memory impairments, personality changes, loss of smell and impaired vision.
Patients who present with symptoms of a glioma undergo a thorough neurological exam that includes checking vision, hearing, balance, coordination and reflexes. In addition, taking images of the brain confirms the presence of the tumor as well as revealing its size, type and location. Knowing which part of the brain the tumor resides in can help determine the type of treatment. For example, tumors in the frontal lobe may allow for removal through surgery, while those in the cerebellum, found under the cerebrum, usually do not. Doctors also take a sample of thee tumor cells, a procedure known as a biopsy, to help confirm the type of tumor.
Treating a brain tumor proves difficult because of the sensitivity of the brain, the accessibility and because many types of medications cannot cross the blood-brain barrier. Because frontal lobe brain tumors often allow access, doctors can perform surgery to remove as much of the tumor as possible. Patients often also receive radiation therapy, the use of high-energy waves, or chemotherapy, the use of toxic medications, to treat any portion of the tumor remaining or any tumor cells that spread.