Online Medicine Resource: Adult Brain Tumours

What are adult brain tumours?

Adult brain tumours are diseases in which cancer (malignant) cells begin to grow in the tissues of the brain. The brain controls memory and learning, senses (hearing, sight, smell, taste, and touch), and emotion. It also controls other parts of the body, including muscles, organs, and blood vessels. Tumours that start in the brain are called primary brain tumours.

What are metastatic brain tumours?

Often, tumours found in the brain have started somewhere else in the body and spread (metastasized) to the brain. These are called metastatic brain tumours.
What are the symptoms of an adult brain tumour?

A doctor should be seen if the following symptoms appear:

Frequent headaches.
Vomiting.
Loss of appetite.
Changes in mood and personality.
Changes in ability to think and learn.
Seizures.

What tests are used to find and diagnose adult brain tumours?

Tests that examine the brain and spinal cord are used to detect (find) adult brain tumour. The following tests and procedures may be used:

CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerised tomography, or computerised axial tomography.
MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of the brain and spinal cord. A substance called gadolinium is injected into the patient through a vein. The gadolinium collects around the cancer cells so they show up brighter in the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI).

Adult brain tumour is diagnosed and removed in surgery. If a brain tumour is suspected, a biopsy is done by removing part of the skull and using a needle to remove a sample of the brain tissue. A pathologist views the tissue under a microscope to look for cancer cells. If cancer cells are found, the doctor will remove as much tumour as safely possible during the same surgery. An MRI may then be done to determine if any cancer cells remain after surgery. Tests are also done to find out the grade of the tumour.

What is the grade of a tumour?

The grade of a tumour refers to how abnormal the cancer cells look under a microscope and how quickly the tumour is likely to grow and spread. The pathologist determines the grade of the tumour using tissue removed for biopsy. The following grading system may be used for adult brain tumours:

Grade I

The tumour grows slowly, has cells that look similar to normal cells, and rarely spreads into nearby tissues. It may be possible to remove the entire tumour by surgery.

Grade II

The tumour grows slowly, but may spread into nearby tissue and may become a higher-grade tumour.

Grade III

The tumour grows quickly, is likely to spread into nearby tissue, and the tumour cells look very different from normal cells.

Grade IV

The tumour grows very aggressively, has cells that look very different from normal cells, and is difficult to treat successfully.

The chance of recovery (prognosis) and choice of treatment depend on the type, grade, and location of the tumour and whether cancer cells remain after surgery and/or have spread to other parts of the brain.

Types of Adult Brain Tumour

The extent or spread of cancer is usually described as stages. There is no standard staging system for brain tumours. Primary brain tumours may spread within the central nervous system (brain and spinal cord), but they rarely spread to other parts of the body. For treatment, brain tumours are classified by the type of cell in which the tumour began, the location of the tumour in the central nervous system, and the grade of the tumour.

Types of adult brain tumours include the following:

Brain Stem Gliomas

These are tumours that form in the brain stem, the part of the brain connected to the spinal cord. They are often high-grade. Brain stem gliomas that are high-grade or spread widely throughout the brain stem are difficult to treat successfully. To prevent damage to healthy brain tissue, brain stem glioma is usually diagnosed without a biopsy.

(Refer to the summary on Childhood Brain Stem Glioma Treatment for more information.)

Pineal Astrocytic Tumour

Pineal tumours form in or near the pineal gland. The pineal gland is a tiny organ in the brain that produces the hormone melatonin, a substance that helps control our sleeping and waking cycle. There are several kinds of pineal tumours. Pineal astrocytic tumours are astrocytomas that occur in the pineal region and may be any grade.

Pilocytic Astrocytoma (grade I)

Astrocytomas are tumours that start in brain cells called astrocytes. Pilocytic astrocytomas grow slowly and rarely spread into the tissues around them. These tumours occur most often in children and young adults. They usually can be treated successfully.

Diffuse Astrocytoma (grade II)

Diffuse astrocytomas grow slowly, but they often spread into nearby tissues. Some of them progress to a higher grade. They occur most often in young adults.

Anaplastic Astrocytoma (grade III)

Anaplastic astrocytomas are also called malignant astrocytomas. They grow rapidly and spread into nearby tissues. The tumour cells look different from normal cells. The average age of patients developing anaplastic astrocytomas is 41 years.

Glioblastoma (grade IV)

Glioblastomas are malignant astrocytomas that grow and spread aggressively. The cells look very different from normal cells. Glioblastoma is also called glioblastoma multiforme or grade IV astrocytoma. They occur most often in adults between the ages of 45 and 70 years.

Refer to the following summaries for more information on astrocytomas:

Childhood Cerebral Astrocytoma/Malignant Glioma Treatment
Childhood Cerebellar Astrocytoma Treatment
Childhood Visual Pathway and Hypothalamic Glioma Treatment

Oligodendroglial Tumours

Oligodendroglial tumours begin in the brain cells called oligodendrocytes, which support and nourish nerve cells. Grades of oligodendroglial tumours include the following:

Oligodendroglioma (grade II): Oligodendrogliomas are slow-growing tumours with cells that look very much like normal cells. These tumours occur most often in patients between the ages of 40 and 60 years.
Anaplastic oligodendroglioma (grade III): Anaplastic oligodendrogliomas grow quickly and the cells look very different from normal cells.

Mixed Gliomas

Mixed gliomas are brain tumours that contain more than one type of cell. The prognosis is affected by the cell type with the highest grade present in the tumour.

Oligoastrocytoma (grade II): Oligoastrocytomas are slow-growing tumours composed of cells that look like astrocytes and oligodendrocytes.
Anaplastic oligoastrocytoma (grade III): These are higher-grade oligoastrocytomas. The average age of patients developing anaplastic oligoastrocytomas is 45 years.

Ependymal Tumours

Ependymal tumours usually begin in cells that line the spaces in the brain and around the spinal cord. These spaces contain cerebrospinal fluid, a liquid that cushions and protects the brain and spinal cord. Grades of ependymal tumours include the following:

Grade I and grade II ependymomas: These ependymomas grow slowly and have cells that look very much like normal cells. They can often be removed completely by surgery.
Anaplastic ependymoma (grade III): Anaplastic ependymomas grow very quickly.

(Refer to the summary on Childhood Ependymoma Treatment for more information.)

Medulloblastoma (grade IV)

Medulloblastomas are brain tumours that begin in the lower back of the brain. They are formed from abnormal brain cells at a very early stage in development. Medulloblastomas are usually found in children or young adults between the ages of 21 and 40 years. This type of cancer may spread from the brain to the spine through the cerebrospinal fluid.

(Refer to the summary on Childhood Medulloblastoma Treatment for more information.)

Pineal Parenchymal Tumours

Pineal parenchymal tumours form from parenchymal cells or pinocytes, the cells that make up most of the pineal gland. These differ from pineal astrocytic tumours, which are astrocytomas that form in tissue that supports the pineal gland. Grades of pineal parenchymal tumours include the following:

Pineocytomas (grade II): Pineocytomas are slow-growing pineal tumours that occur most often in adults aged 25 to 35.
Pineoblastomas (grade IV): Pineoblastomas are rare and highly malignant. They usually occur in children.

(Refer to the summary on Childhood Supratentorial Primitive Neuroectodermal Tumours and Pineoblastoma Treatment for more information.)

Meningeal Tumours

Meningeal tumours form in the meninges, thin layers of tissue that cover the brain and spinal cord. Types of meningeal tumours include the following:

Grade I meningioma: Meningiomas are the most common meningeal tumour. Grade I meningiomas are slow-growing and benign. They are found most often in women.
Grade II and III meningiomas and hemangiopericytomas: These are rare malignant meningeal tumours. They grow quickly and are likely to spread within the brain and spinal cord. Grade III meningiomas are more common in men. Hemangiopericytomas often recur after treatment and most of them spread to other parts of the body.

Germ Cell Tumour

Germ cell tumours arise from germ cells, cells that are meant to form sperm in the testicles or eggs in the ovaries. These cells may travel to other parts of the body and form tumours. Types of germ cell tumours include germinomas, embryonal cell carcinomas, choriocarcinomas, and teratomas. They can occur anywhere in the body and can be either benign or malignant. In the brain, they usually form in the center, near the pineal gland, and can spread to other parts of the brain and spinal cord. Most germ cell tumours occur in children.

(Refer to the summary on Childhood Brain Tumours for more information.)

Craniopharyngioma (grade II)

Craniopharyngiomas occur in the sellar region of the brain, near the pituitary gland. The pituitary gland is a small organ about the size of a pea, located at the base of the brain. This gland controls many of the body's functions, especially growth. In adults, these tumours occur most often after the age of 50 years. Craniopharyngiomas can press on vital brain tissue and cause symptoms to appear. The tumours can also block fluid in the brain and cause swelling. The prognosis is good for craniopharyngiomas that are completely removed in surgery.

Pituitary tumours also occur in this region. Refer to the summary on Pituitary Tumour Treatment for more information.

Other Adult Brain Tumours

For information about other types of adult brain tumours, refer to the health professional summary on Adult Brain Tumours.

Recurrent Adult Brain Tumour

Recurrent adult brain tumour is a tumour that has recurred (come back) after it has been treated. Adult brain tumours often recur, sometimes many years after the first tumour. The tumour may come back in the brain or in other parts of the body.

Metastatic Brain Tumours

The types of cancer that commonly spread to the brain are cancers of the lung, breast, unknown primary site, melanoma, and colon. About half of metastatic spinal cord tumours are caused by lung cancer.

Prognosis depends on the following:

Whether the patient is younger than 60 years.
Whether there are fewer than 3 tumours in the brain and/or spinal cord.
The location of the tumours in the brain and/or spinal cord.
How well the tumour responds to treatment.
Whether the primary tumour continues to grow or spread.

The prognosis is better for brain metastases from breast cancer than from other types of primary cancer. The prognosis is worse for brain metastases from colon cancer.

Treatment Option Overview

How are adult brain tumours treated?

Different types of treatment are available for patients with adult brain tumour. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. Before starting treatment, patients may want to think about taking part in a clinical trial. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment.

Clinical trials are taking place in many parts of the country. Information about ongoing clinical trials is available from the NCI Web site. Choosing the most appropriate cancer treatment is a decision that ideally involves the patient, family, and health care team.
Three types of standard treatment are used.

Surgery

Surgery is used, when possible, to treat adult brain tumour, as described in the Description section of this summary.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). A dissolving wafer may be used to deliver an anticancer drug directly into the brain tumour site after the tumour has been removed by surgery. The way the chemotherapy is given depends on the type and stage of the cancer being treated.
Other types of treatment are being tested in clinical trials.

New methods of delivering radiation therapy

Radiosensitizers: Drugs that make tumour cells more sensitive to radiation. Combining radiation with radiosensitizers may kill more tumour cells.
Hyperfractionation: Radiation therapy given in smaller-than-usual doses two or three times a day instead of once a day.
Stereotactic radiosurgery: A radiation therapy technique that delivers radiation directly to the tumour with less damage to healthy tissue. The doctor uses a CT scan or MRI to find the exact location of the tumour. A rigid head frame is attached to the skull and high-dose radiation is directed to the tumour through openings in the head frame, reducing the amount of radiation given to normal brain tissue. This procedure does not involve surgery. This is also called stereotaxic radiosurgery and gamma knife therapy.

Hyperthermia therapy

Hyperthermia therapy is a treatment in which body tissue is exposed to high temperatures to damage and kill cancer cells or to make cancer cells more sensitive to the effects of radiation and certain anticancer drugs.

Biologic therapy

Biologic therapy is a treatment that uses the patient’s immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body’s natural defenses against cancer. This type of cancer treatment is also called biotherapy or immunotherapy.
How are metastatic brain tumours treated?

Tumours that have spread to the brain from somewhere else in the body are usually treated with radiation therapy and/or surgery. Chemotherapy may be used if the primary tumour is the kind that responds well to chemotherapy. Clinical trials are under way to study new treatments.

Treatment Options by Type of Adult Brain Tumour

Brain Stem Gliomas

Treatment of brain stem gliomas may include the following:

1. Hyperfractionated radiation therapy.
2. A clinical trial of new anticancer drugs and/or biologic therapy.

Pineal Astrocytic Tumours

Treatment of pineal astrocytic tumours may include the following:

1. Surgery and radiation therapy, with or without chemotherapy.
2. A clinical trial of external radiation therapy plus hyperthermia therapy or new methods of delivering radiation therapy.
3. A clinical trial of new anticancer drugs and biologic therapy following radiation therapy.

Pilocytic Astrocytomas

Treatment of pilocytic astrocytoma is usually surgery with or without radiation therapy.
Diffuse Astrocytomas

Treatment of diffuse astrocytoma may include the following:

1. Surgery, usually with radiation therapy.
2. A clinical trial of surgery and radiation therapy with or without chemotherapy for tumours that cannot be completely removed by surgery.
3. A clinical trial of radiation therapy delayed until the tumour progresses.
4. A clinical trial comparing high-dose and low-dose radiation therapy.

Anaplastic Astrocytomas

Treatment of anaplastic astrocytoma may include the following:

1. Surgery plus radiation therapy, with or without chemotherapy.
2. A clinical trial of external radiation therapy plus hyperthermia therapy or new methods of delivering radiation therapy.
3. A clinical trial of new anticancer drugs and biologic therapy following radiation therapy.
4. A clinical trial of chemotherapy combined with different methods of delivering radiation therapy.

Glioblastoma

Treatment of glioblastoma may include the following:

1. Surgery plus radiation therapy, with or without chemotherapy.
2. A clinical trial of chemotherapy placed into the brain during surgery.
3. A clinical trial of radiation and concurrent chemotherapy.
4. A clinical trial of external radiation therapy plus hyperthermia therapy or new methods of delivering radiation therapy.
5. A clinical trial of new anticancer drugs and biologic therapy following radiation therapy.
6. A clinical trial of chemotherapy and new methods of delivering radiation therapy.
7. Clinical trials of new treatments.

Oligodendroglial Tumours

Treatment of oligodendrogliomas may include the following:

Treatment of anaplastic oligodendroglioma may include the following:

1. Surgery plus radiation therapy with or without chemotherapy.
2. A clinical trial of external radiation therapy plus hyperthermia therapy or new methods of delivering radiation therapy.
3. A clinical trial of new anticancer drugs and biologic therapy following radiation therapy.

Mixed Gliomas

Treatment of mixed gliomas may include the following:

Ependymal Tumours

Treatment of grade I and grade II ependymomas is usually surgery with or without radiation therapy.

Treatment of anaplastic ependymoma may include the following:

1. Surgery plus radiation therapy.
2. A clinical trial of surgery followed by chemotherapy before, during, and after radiation therapy.
3. A clinical trial of chemotherapy and/or biologic therapy.

Medulloblastoma

Treatment of medulloblastomas may include the following:

1. Surgery plus radiation therapy to the brain and spine.
2. A clinical trial of surgery and radiation therapy to the brain and spine for tumours that are more difficult to treat successfully.
3. A clinical trial of chemotherapy.

(Refer to the summary on Childhood Medulloblastoma Treatment for more information.)
Pineal Parenchymal Tumours

Treatment of pineal parenchymal tumours may include the following:

Meningeal Tumours

Treatment of meningiomas may include the following:

1. Surgery with or without radiation therapy.
2. Radiation therapy for tumours that cannot be removed by surgery.

Treatment of malignant meningioma may include the following:

1. Surgery plus radiation therapy.
2. A clinical trial of external radiation therapy plus hyperthermia therapy or new methods of delivering radiation therapy.
3. A clinical trial of new anticancer drugs and/or biologic therapy following radiation therapy.

Germ Cell Tumours

Treatment of central nervous system germ cell tumours depends on the type of cancer cells, the location of the tumour, whether the cancer can be removed in an operation, and other factors.
Craniopharyngioma

Treatment of craniopharyngiomas may include the following:

1. Surgery to remove the entire tumour.
2. Surgery to remove as much of the tumour as possible, followed by radiation therapy.

Recurrent Adult Brain Tumour

Treatment of recurrent adult brain tumours may include the following:

1. Surgery with or without chemotherapy.
2. Radiation therapy, if not used during previous treatment, with or without chemotherapy.
3. Internal radiation therapy.
4. Chemotherapy.
5. A clinical trial of new anticancer drugs.
6. A clinical trial of chemotherapy placed into the brain during surgery.
7. A clinical trial of biologic therapy.

Metastatic Brain Tumours

Treatment of a single metastatic brain tumour is usually surgery followed by radiation therapy to the brain.

Treatment of more than one metastatic brain tumour may include the following:

1. Radiation therapy to the brain.
2. Surgery, for large tumours that are pressing on areas of the brain and causing symptoms.