Brain tumors are divided into many classifications. Primary brain tumors refer to tumors that originate in the brain, and metastatic tumors are tumors that originate elsewhere in the body and travel through the bloodstream to the brain. Primary brain tumors may be either benign or malignant. Metastatic tumors are malignant.
Most tumors are biopsied prior to treatment. In cases where the tumor is adjacent to vital structures, a decision may be made prior to surgery to perform only a biopsy rather than attempting to remove the entire tumor.
Some brain tumors do not produce symptoms. Other times, symptoms may include headaches (especially at night), seizures or neurological difficulties related to speech, vision, numbness, weakness, balance or walking.
The total treatment of brain tumors is a team effort. This involves the neurosurgeon, the medical oncologist, the radiation oncologist, their staffs and the patient and family. New treatments are being developed rapidly and the prognosis for patients with brain tumors is brighter than it ever was in the past.
For additional information about brain tumors and their treatment, visit the American Brain Tumor Association atwww.abta.org, the National Brain Tumor Foundation at www.braintumor.org or the Acoustic Neuroma Association at www.anausa.org.
Specific brain tumors are:
Craniopharyngioma are benign slow-growing tumors, either solid or cyst, that arise from the stalk that connects the pituitary gland to the brain. Located behind the eyes, a craniopharyngioma may cause vision problems, headaches, nausea, and difficulty with balance if it exerts pressure on the brain. It also may interfere with the production of hormones from the pituitary gland. However, not all patients will experience symptoms.
Gliomas are primary tumors. Gliomas are graded, or divided, into levels based upon their rate of growth and potential for rapid deterioration. The higher the grade, the more aggressive the tumor. Treatments for gliomas depend upon the grade and will typically involve a combination of therapies including surgical removal, chemotherapy and radiation. Astrocytomas, the most common of these tumors, are tumors that sprout from abnormal astrocyte cells, which support neuron function and generation in the brain, among other things. Astrocytomas are graded on a scale of 1 through 4, with 4 the most serious form. Symptoms vary, and may include mental dysfunction, seizures, persistent headaches, vomiting or swelling. The standard treatment is surgery if the tumor is accessible, followed by radiation therapy and chemotherapy. In grades 3 and 4, there is a high probability that the tumor will return, so follow up treatment and diligent follow up is essential.
Meningiomas are tumors of the meninges or coverings of the brain. The majority are benign. Acoustic neuromas and pituitary tumors are other common benign tumors. They may be treated with surgical removal, radiation or stereotactic radiosurgery using gamma knife technology. The type of treatment depends upon the size and location of the tumor, surrounding critical structures, and the patient’s general health and well-being.
Metastic tumors: A cancer in one part of the body can spread to the central nervous system, which includes the brain, cranial nerves, and spinal cord. These secondary tumors are called metastases or metastatic tumors. Increasingly, metastatic tumors are treated without surgery, using the gamma knife technology. Lung, breast, melanoma, renal and colon cancers account for the greatest majority of all brain metastasis.
The tumors generally increase pressure in the brain, resulting in headache and vomiting. Other symptoms may include, muscle weakness, behavioral changes, confusion, a sudden seizure, and changes in vision, ability to speak, balance, and sensory perceptions.
Surgery is an important part of the management for some patients with brain metastasis. During surgery, first tissue is obtained to confirm the diagnosis. Then the tumor, also called a lesion, is removed. Surgery is performed when the treating physician determines that it is likely to lead to greater relief of symptoms than might be achieved by other treatments and it possibly can extend survival.
Oligodendroglioma is a type of glioma and develops from cells called oligodendrocytes, which produce the fatty covering that insulates the electrical transmission carried by nerve cells. Often formed in the frontal or temporal lobes, an oligodendroglioma either grows slowly or quickly — known as an anaplastic oligodendroglioma. The tumor may originate as a benign growth, but over time it can develop into a malignant lesion. The location of the tumor produces different symptoms. In the frontal lobe, a tumor may affect mood and personality and possibly cause paralysis on one side of the body. In the temporal lobe a tumor may affect coordination, speech and memory.
When detected early, a small tumor may be treated using stereotactic surgery, such as gamma knife treatment. However, a more developed lesion may infiltrate healthy brain tissue, which may require traditional surgery. For more information, visit http://www.braintumorfoundation.org/educate-yourself/tumor-types/oligodendrogliomas.
Pituitary tumors: Most pituitary tumors are benign, which means they are non-cancerous, grow slowly and do not spread to other parts of the body. However, they may affect the pituitary gland’s hormone production, which can create problems in the body. Tumors that affect hormone production are called functioning tumors; tumors that don’t affect hormone production are called non-functioning tumors. Pituitary tumor symptoms materialize as the tumor grows and may include headaches, vision problems, nausea, and vomiting. Hormone disorders caused by functioning tumors will produce symptoms specific to the affected hormone production. Sometimes they can be treated by radiation alone. At other times, stereotactic radiosurgery or endoscopic surgery may be indicated. More information is available at www.ninds.nih.gov/disorders/pituitary_tumors/pituitary_tumors.htm
Skull Base Tumors: Many different tumor types originate from or extend into the base or bottom of the skull, upon which the brain rests. Because the front of the skull base slopes down behind the eyes and nasal cavities, skull base tumors require considerable surgical skill to avoid damage vital nerves and tissues. Skull base tumors may be benign or malignant and produce few symptoms until they grow large enough. Symptoms vary depending of the location and size of the tumor and may include facial pain or numbness, headache, recurrent sinusitis, cranial nerve palsies, nasal obstruction, shortness of breath, hoarseness, hearing loss or tinnitus (ringing in the ears). Increasingly, skull base tumors may be excised using endoscopic surgery through the nasal passages, but many still require open surgery. The tumor may be excised through traditional open surgery or endoscopic microsurgery through the nasal passages. In some causes, particularly when the entire tumor cannot be safely removed, surgery is followed by radiation therapy, which can be traditional or gamma knife surgery.