I. Types of Brain Tumors A brain tumor is an abnormal proliferation of cells in the brain. While this abnormal growth of cells is commonly referred to as a brain tumor, not all brain tumors are cancers. Cancer is a specific term for malignant tumors. Malignant tumors grow and spread rapidly, encroaching on healthy cells’ living space, blood supply and nutrients (like all cells in the body, tumor cells depend on blood and nutrients to survive). Jiang Zhongli, Department of Neurosurgery, Beijing Tiantan Hospital Tumors that do not spread or metastasize are called benign tumors. Generally speaking, benign tumors do not cause as much harm as malignant tumors. However, benign tumors in the brain can still cause many problems. 1. Primary Brain Tumors The brain is made up of many different types of cells. Brain tumors form when one type of cell shifts from its normal characteristics. Once the transformation occurs, the cells grow and proliferate in an abnormal way. These abnormal cells grow into a mass, or tumor. Masses formed by brain cells that transform and grow in this abnormal way are called primary brain tumors because they originate in the brain tissue itself. The most common primary brain tumors include gliomas, meningiomas, pituitary adenomas, acoustic neuromas, and primitive neuroectodermal tumors (medulloblastomas). Neurogliomas include astrocytomas, oligodendrogliomas, ventricular meningiomas, and choroid plexus papillomas. Most of these brain tumors are named according to their site of origin or cell of origin. Metastatic Brain Tumors Metastatic brain tumors are caused by the metastasis of cancer cells from tumors in other parts of the body to the brain. The process of moving cancer cells from other parts of the body to brain cells is called metastasis. About 25% of tumors in other parts of the body can metastasize to the brain. Like tumors in other parts of the body, the exact cause of brain tumors is unknown. Genetic factors, various environmental toxins, radiation, and smoking are all associated with the development of brain tumors, but in most cases, no clear cause can be found. Risk factors for primary brain tumors include: 1. Radiation to the cranial region; 2. Specific genetic predisposition; and 3. HIV infection. However, it is uncertain whether these factors actually increase your risk of developing a brain tumor. Not all brain tumors produce symptoms, and some (such as pituitary tumors) are often discovered after death. Brain tumor symptoms are numerous but not specific, which means that they can also be seen in a wide range of other conditions. The only way to determine what is causing the clinical symptoms is to perform diagnostic tests. Some symptoms are due to pressure from the tumor or invasion of other parts of the brain that interfere with the work of normal tissues. Some symptoms arise as a result of brain edema caused by inflammation in or around the tumor itself. The symptoms produced by primary brain tumors are similar to those produced by brain metastases. The most common symptoms of brain tumors are as follows: (1) headache; (2) weakness; (3) clumsy behavior; (4) difficulty in walking; (5) seizures. The non-specific symptoms of brain tumors are as follows: (1) changes in mental status, concentration, memory, attention and state of mind; (2) nausea, vomiting – especially in the morning; (3) visual abnormalities; (4) speech difficulties; (5) progressive mental retardation or mood changes. For most people, these symptoms appear very slowly and may go unnoticed by the brain tumor patient and his or her family. Sometimes, however, they appear very quickly. In some cases, the patient may act as if he or she has had a stroke. Seek immediate help from your doctor for any of the following symptoms: (1) unexplained, persistent vomiting; (2) double vision or unexplained blurred vision, especially on one side; (3) drowsiness or prolonged sleep; (4) new epilepsy; and (5) new headache. Although headaches are considered a common symptom of brain tumors, they may not appear until the disease is advanced. If the nature of your headaches changes significantly, this may prompt you to go to the hospital for further testing. If you already have a brain tumor, any new symptoms, as well as a relatively sudden or rapid worsening of existing symptoms, should prompt a visit to the emergency room of your nearest hospital. 4. Recognize the following new symptoms in advance: (1) seizures; (2) mental changes such as excessive sleepiness, memory problems, or inability to concentrate; (3) visual changes and other sensory abnormalities; (4) poor speech or impaired language expression; (5) behavioral and personality changes; (6) clumsiness or difficulty in walking; (7) nausea or vomiting (especially in the middle-aged or elderly); and (8) sudden fevers, especially with chemotherapy; and (9) a sudden increase in the number of symptoms. Sudden fever, especially after chemotherapy. For your doctor, the findings of your consultation and physical examination may help them to determine whether you have a cranial brain disease. In most cases, you will have a CT scan of the brain, which is similar to an X-ray and shows three-dimensional details. Usually, a harmless contrast material is injected into a blood vessel so that the abnormal part is highlighted on the scan. Patients with brain tumors often have other medical problems, so routine laboratory tests may also be performed. These include blood analysis, electrolytes, liver function and blood clotting tests. If you have mental changes as your main symptom, blood and urine tests may rule out drug use as the cause. Gradually, MRI scans are replacing CT scans in the diagnosis of suspected brain tumors because of their high sensitivity in monitoring tumor development. Nowadays, however, most institutions still use CT as the diagnostic test of choice for brain tumors. Cranial x-rays are no longer routinely used in the diagnosis of brain tumors. If your examination reveals that you have a brain tumor, you should consult an oncologist, preferably one in neuro-oncology, if available. The next step is to determine if you have cancer, and a tumor biopsy can determine the type of tumor. The most common method of biopsy is surgery, craniotomy and if possible, total removal of the tumor, taking a biopsy along the way. If the tumor cannot be completely removed, only a small piece of tumor tissue can be biopsied. Some cases can avoid craniotomy to take a biopsy, using CT or MRI scanning stereotactic accurate location of the tumor, drilling a small hole in the skull, puncture needle through the small hole to reach the tumor, biopsy, this technique is presented as stereotactic biopsy. Pathologists observe the biopsy tissue through microscope (pathologists are doctors who specialize in diagnosing diseases by observing cells and tissues), combined with molecular biology examination to clarify the nature of the tumor. Brain tumor treatment Brain tumor treatment should be individualized: according to age, physical condition, tumor size, location and type, individualized choice of treatment plan. You and your family will have many questions about your tumor and its treatment, such as how will the treatment affect you and what is your prognosis? The healthcare provider treating you will give you serious answers, so don’t hesitate to ask. Treatment for brain tumors is comprehensive, and most treatment plans include many consulting physicians. The team of doctors includes neurosurgeons, oncologists, radiation oncologists also include dietitians, social workers, physical therapists, and possibly other specialists. Treatment protocols need to be tailored to the location, size and type of tumor, your age, and health status. The most common methods are surgery, radiation therapy and chemotherapy, and many cases require a combination of these methods. 1. Surgery Most patients with brain tumors require surgery. The purpose of surgery is to identify the tumor and remove it. If the tumor cannot be removed, surgery can biopsy the tumor to determine its type. In some cases, most benign tumors, symptoms can be completely cured by surgical removal of the tumor. If possible, the surgeon will try to remove the tumor. Stereotactic surgery is a new technique for removing brain tumors without opening the skull. It uses CT or MRI scans to determine the location of the tumor and irradiates the tumor with high-energy rays from different angles to destroy the tumor, a technique commonly referred to as the Gamma Knife. This new technique has fewer post-operative complications and a shorter recovery period. Before surgery, you will receive many treatments. You will take steroid hormones, such as dexamethasone to reduce edema. You will take anticonvulsant medications, such as carbamazepine (Deltoid) to reduce or prevent seizures. If you have hydrocephalus, you will receive a cerebrospinal fluid shunt, where one end of a tube is placed inside the ventricles of the brain and the other end is placed through the skin in another part of the body to facilitate the removal of cerebrospinal fluid. 2.Radiation therapy Radiation therapy (also known as radiotherapy) uses high-energy rays to destroy tumor cells to stop them from growing and multiplying. Radiotherapy is used for patients who cannot be operated on, and is also used after surgery to remove tumors left over from surgery. Radiotherapy is a localized treatment that kills only the target cells and has no effect on other cells in the body and brain. There are two types of radiation therapy: External radiation therapy is the targeted irradiation of the tumor with high-energy rays that pass through the skin, skull, healthy brain tissue, and other tissues to reach the tumor. This type of treatment is given five times a week for about a few minutes each time, in four- or six-week sessions. Internal radiotherapy is to place a micro radiation capsule inside the tumor, the radiation is emitted from the capsule to kill the tumor, the amount of radiation in the capsule will be gradually reduced, the amount of radiation is accurately calculated to give the optimal dose, you need to stay in the hospital for a few days when you receive the treatment. 3.Chemotherapy Chemotherapy is the use of powerful drugs to kill tumor cells, alone or in combination. The drugs are given orally or intravenously, and some are given through a cerebrospinal fluid shunt. Chemotherapy is divided into courses. A course of chemotherapy includes a medication period and a recovery period, and a course of chemotherapy usually lasts for a few weeks. Completion of 2-3 courses will be observed to see how the tumor responds to treatment. The side effects of chemotherapy are well known and are difficult for some patients to tolerate. Such as nausea, vomiting, mouth ulcers, loss of appetite, and loss of hair. Medications can alleviate some of the side effects.