Brain Tumor Treatment and Surgery
Brain tumors do not discriminate by gender, age, or race. They can affect anyone.
What Is a Brain Tumor?
A brain tumor is defined as a mass of unnecessary and abnormal cells growing in the brain. When a cell divides too rapidly because internal mechanisms that regularly check its growth are damaged, the cell can eventually grow into a tumor. Symptoms or signs of a brain tumor can be caused by pressure on the brain and surrounding tissues or by irritation of neural structures. Extreme irritation of nerve tissue (which may result in seizures) or loss of function may occur.
Types of Brain Tumors
Brain tumors can be classified into two main types: primary or metastatic. Primary brain tumors originate from the cells of the brain or its immediate surroundings and usually remain within the brain. Metastatic (secondary) brain tumors are tumors that originate elsewhere in the body, such as the breast or lung, and spread to the brain, most often through the bloodstream. Primary tumors may be either benign (slow-growing or less aggressive) or malignant (cancerous, fast-growing, or more aggressive). Metastatic tumors are cancerous (malignant).
Brain tumors vary widely in terms of their location, the type of tissue involved, and their degree of malignancy. In adults, tumors originating from the inner lining of the skull are among the most common benign brain tumors. These are called meningiomas. Other common benign tumors are those arising from large nerves at the base of the brain (vascular brain tumors such as hemangioblastoma are more rare). These are called schwannomas. Vestibular schwannomas (also known as acoustic neuromas) are benign tumors of nerves that are important in hearing and balance. They tend to grow very slowly. Tumors of the pituitary gland are also common. They are referred to as pituitary adenomas.
Rarely, all these types of benign tumors may become malignant. In addition, unless treatment manages to destroy or remove every tumor cell, even benign tumors can recur or continue to grow, sometimes many years after their initial treatment.
Tumors that arise from brain tissue range from relatively slowly growing tumors (low-grade) to rapidly growing and highly destructive tumors (high-grade). Gliomas are tumors that arise not from nerve cells, but rather from cells called glial cells or astrocytes, which support and assist nerve cells. A common type of high-grade glioma is the glioblastoma. An ependymoma is a type of glioma that arises from ependymal cells, which line the fluid spaces of the brain and center of the spinal cord. Oligodendrogliomas form from a type of glial cell called an oligodendrocyte.
The most common glial tumors in children and adults are astrocytomas. Astrocytomas are tumors formed by astrocytes, which are an abundant type of glial cell named for their star-like shape. Some types of astrocytomas that are seen most commonly in children are considered to be benign tumors, but astrocytomas that occur in adults are more commonly malignant. Anaplastic astrocytomas are intermediate in aggressiveness between astrocytomas and glioblastomas.
What Causes a Brain Tumor?
The causes of brain tumors are still unknown. Thus, they cannot be prevented. However, research indicates that brain tumors appear when specific genes on the chromosomes of a cell are damaged and no longer function properly. Many of these genes help to regulate the rate at which a cell divides. Others repair damage to the cell’s genes. In still other cases, damage to a gene may interfere with a cell’s planned self-destruction. Some individuals may be born with partial defects in one or more of these genes.
Symptoms of a Brain Tumor
Symptoms of a brain tumor may include headaches, nausea, vomiting, seizures, weakness on one side of the body, an unbalanced walk, behavioral and cognitive symptoms, vision or hearing problems, balance problems, or memory and personality changes.
Diagnosing a Brain Tumor
Tumors are usually diagnosed by radiologic examinations, including MRI and CT scans. Before your doctor can recommend a course of treatment, you need to be thoroughly evaluated. Your evaluation may include a medical history, physical examination, thorough neurological examination, and diagnostic tests. Your doctor will document your symptoms and determine the extent to which these symptoms affect your daily living. He or she can then order various diagnostic tests to determine more precisely the nature and extent of the tumor.
Diagnostic tests that are used to determine the status of a tumor may include:
Angiogram: This test can identify the blood vessels supplying a brain tumor.
Computed Tomography (CT): A CT (also known as a CAT scan) provides anatomical information about the status of organs and tissues. This test uses an x-ray beam to[ produce a two-dimensional computerized map of the body.
Magnetic Resonance Imaging (MRI): The MRI uses a powerful magnetic field to produce a detailed anatomical picture of the head or spine and surrounding structures. This test measures the health of cells and how well they are functioning.
Positron Emission Tomography (PET): This test can map the biological function of an organ, detect subtle metabolic changes, and sometimes even help to determine if a tumor is benign or malignant.
The treatment options for a tumor depend primarily on its size, type and location, and on the age and overall health of the patient. Brain tumors (whether primary or metastatic, benign or malignant) are usually treated with surgery, radiation, and/or chemotherapy – alone or in various combinations.
It is generally accepted that complete or nearly complete surgical removal of a brain tumor is beneficial for a patient. The primary goal of surgery is to remove as much of the tumor as possible without injuring brain tissue important to the patient’s neurological function (such as the ability to speak, walk, use his or her hands, etc.). If the tumor cannot be completely removed, surgery can still reduce or control tumor size. New surgical techniques can minimize the risk and discomfort of surgery.
In most cases, surgeons create a large opening (or “craniotomy”) to ensure that they can get to a tumor. Subtle differences in appearance between normal tissue and a tumor are used to guide its removal.
Sometimes a biopsy is obtained before proceeding with a large operation. The biopsy can be obtained through a smaller craniotomy or with special guidance techniques to obtain a “stereotactic biopsy.” A stereotactic biopsy is performed when a neurosurgeon uses a small instrument that is guided in three dimensions to remove a small sample of tissue from an area of the brain. Computers are used to determine precise information about tumor location from a CT or MRI scan. Often, a small piece of tumor may be retrieved through an opening in the skull that is only a few millimeters wide. The goal of a biopsy is to obtain a small sample of tissue to guide doctors in determining the best treatment plan.
Sophisticated surgical navigation systems are also used to assist the surgeon with localization and orientation. These systems allow surgeons to accurately correlate a position inside the brain with what is seen on imaging studies (CT, MRI, PET, angiograms). This guidance information may reduce the risks and improve the extent of tumor removal.
The choice of treatment and the decision as to when to perform an operation should be determined by a neurosurgeon. It is important to keep in mind that surgery does have its limitations. Although every precaution will be taken to avoid complications, potential risks may include infection, excessive bleeding both during and after surgery, difficulty swallowing, stroke, seizures, weakness or paralysis, and other problems. Ask your doctor to speak with you about potential side effects.
Radiation and chemotherapy are treatment options that can be used independently to treat or in conjunction with surgery. The surgeons of Lansing Neurosurgery work closely with oncologists during this period of treatment.
Content Source: Clinic of Neuro Surgergy