Revised March 1999
Headlines: a newsletter for Brain Tumour patients.
General Information/ Anatomy/ Function/ Statistics
- The brain and spinal cord together constitute the central nervous system (C.N.S.)
- Provides the structural and functional framework for thought, memory and emotion
- Permits us to reason, analyze etc.
- Processes sensory and motor functions
- The brain is a complex organ composed of different tissues including the electro-chemical connections (neurons) and supporting tissues, most of which are able to develop tumours
- Tumours rarely spread to other parts of the body
- They spread by local infiltration and may be extensive before functional changes occur
- Some are slow growing and push the normal surrounding brain tissue aside
- Neither benign nor malignant tumours have much room to expand
- The skull is a solid container completely filled by the normal brain and any growth may cause compression and pressure inside the head
- Primary brain tumours account for 3% of all neoplasms but is the most common solid tumour of children, accounting for 25% of all pediatric malignancies
- 2,170 new brain tumours occur in Canada yearly
- 80% of brain tumours occur in adults between the ages of 50 and 60
- Brain tumours that occur in childhood often behave very differently from those that happen in adulthood
- For statistics, please see Statistics by Cancer Type
Symptoms/ Signs
- Headache
- May be due to pressure inside the brain from tumour mass itself or swelling
- Can be caused by distortion of the outer membrane or blood vessels of the brain by the tumour
- May be associated with vomiting, double vision, decreased visual acuity, drowsiness
- Pain may be worsened by coughing or straining
- Seizures
- partial or full seizures may be due to either tumour, brain swelling or to scar formation
- Neurological Dysfunction
- May affect speech, memory, vision
- Localized weakness or sensory loss due to invasion or compression of adjacent brain tissue
- The resultant neurologic loss dependant on the location of the tumour
Etiology/ Carcinogens/ Risks
- No proven cause-effect relationship
- Heredity and cancer-causing genes (oncogenes) may play a part, especially in children
- Associations have been described with exposure to chemicals/ fumes; radiation; viruses
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading/ Types
- Full history and physical examination
- Neurological examination
- May include routine blood work and screening
- Chest x-ray
- CT scan which shows the position and nature of the tumour
- Magnetic Resonance Imaging (MRI) (not always performed)
- Biopsy performed to assess tumour type
Types
Treatment
Surgery
- Almost always surgery is indicated to obtain tissue for diagnosis and resection of the tumour if possible
- Biopsy may be done through a small hole or craniotomy
- Surgical removal involves a craniotomy in which a flap of bone is temporarily removed
- How much of the growth can be removed without damage to nearby structures can often only be determined only at the time of the operation
- If total removal is impossible the neurosurgeon will often remove as much of the tumour as possible
- Partial removal does remove pressure from the tumour within the skull
- Surgeons may also perform shunting procedures for short term relief of pressure or long term control of symptoms
Radiation Therapy
- The most effective single treatment in glial tumours
- Also useful to patients with metastatic tumours originating in the lung and breast, etc.
- There may be loss of hair, fatigue and other relatively minor early side effects. Late effects may affect short term memory
- After 18 to 24 months following dosage of up to 6000 rads, there may be damage to brain cells and small arteries. This usually results in subtle to moderate changes
- Pion therapy: not more effective than conventional radiation, therefore, no longer available for use in brain tumours
Chemotherapy
- Of some benefit to brain tumour patients. Used in some tumour types
- Sometimes used for recurrent tumours - not curative, may cause tumour remission
- Other drugs are used in the overall treatment; e.g., steroids help reduce swelling from tumours and anti-convulsant drugs are often administered on a preventive basis
- Dexamethasone, a steroid, reduces the swelling around brain tumours - may cause swelling of the face, or of the abdomen - may be given at the same time as radiation/ chemotherapy
Gliomas
- Largest group of primary brain cancers
- Account for 45% of all cancers arising from brain cells
- Several major categories
Low Grade Astrocytoma - Grade 1,2
General Information/ Anatomy/ Function/ Statistics
- Member of glioma group
- Named for the type of cell from which it originates
- Generally not as aggressive as higher grades (3,4)
- Relatively low degree of malignancy but after several years some undergo transformation into a more aggressive form
- Survival up to 10 years after onset is common - average is 5 to 6 years
- Survival depends on location and degree of malignancy
Symptoms/ Signs
- Possible movement disorders in children
- Adults may have minor vague symptoms that may remain undiagnosed for years
- Unexplained headaches
- Thought or memory disorders
- Seizures
- Eventual progression of symptoms leads to diagnosis
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading/ Types
- See Diagnosis in general CNS section
- CT scan often does not delineate tumour well
- MRI is usually the best imaging modality in low grade tumours
Treatment
- Surgery is curative if complete removal is achieved
- If surgery is incomplete, radiation therapy is used either immediately or delayed until time of progression
- Chemotherapy is of no proven benefit
ii. High Grade Astrocytoma - Grade 3,4
General Information/ Anatomy/ Function/ Statistics
- Accounts for approximately 25% of primary brain tumours; thus more than half of all gliomas
- Most malignant of all brain cancers
- Steadily infiltrates surrounding tissue
- Typical patients are middle-aged
- 50% will live about twelve months after surgery
- A small number of patients are alive and function at an acceptable level after two years
- Tumour growth and increasing intracranial pressure complicate later stages
Symptoms/ Signs
- Depends on location of tumour in the brain
- Symptoms may be rapidly progressive
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading/ Types
- CT scan usually images the tumour well
- Graded according to their microscopic appearance
- Higher-grade is more aggressive and almost always recur
Treatment
- Surgery is performed for biopsy or attempt at removal
- Often cannot be removed entirely
- Decompression of the intracranial pressure and reduction of tumour bulk may relieve symptoms
- Post-surgery radiation is almost always recommended
- Chemotherapy is often used in grade 3 tumours and may be used in some grade 4 tumours
iii. Ependymoma
General Information/ Anatomy/ Function/ Statistics
- Member of glioma group
- These tumours originate in the linings of the ventricles, which are the central spaces in the brain that produce and contain the cerebrospinal fluid
- Typical location is the fourth ventricle, one of the narrowest and most easily blocked channels
- Most common in children and young adults
- Represents 60% of the spinal cord tumours
- Slow growing; however, they have a high incidence of recurrence
- Tumour can later recur in a more invasive form
- Most patients do well for a long period of time
Symptoms/ Signs
- Initial symptoms related to increased intracranial pressure and hydrocephalus
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading/ Types
- See Diagnosis section under general section of Central Nervous System
Treatment
- Surgery is the major treatment
- Post-operative radiation is almost always recommended
- Shunting procedures relieve intracranial pressure
- Chemotherapy may be used at recurrence
iv. Oligodendroglioma
General Information/ Anatomy/ Function/ Statistics
- Also member of the glioma group
- Slow growing tumour arising in the white matter of the cerebral hemisphere
- Survival average 4 to 5 years
- Similar to low grade astrocytoma
- Transformation into a more malignant grade of cell type can occur
Symptoms/ Signs
- See Symptoms section under general section Central Nervous System
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading/ Types
- See Diagnosis section under general section of Central Nervous System
Treatment
- Surgery is curative if complete removal is achieved
- If surgery is incomplete radiation therapy is used either immediately or delayed until time of progression
- Very responsive to chemotherapy; may be used alone or with radiation
v. Other: Medulloblastoma
General Information/ Anatomy/ Function
- Fast growing tumour that originates in the lower brain near vital structures and cerebrospinal fluid channels (cerebellum)
- Propensity to spread throughout the craneal-spinal axis
- Commonly occurs in children and young adults
Symptoms/ Signs
- Evident early in the disease
- Apathy
- Headache
- Unexplained vomiting
- Difficulty in walking
- Papilledema (swelling of the optic nerve on examination of the eye)
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading/ Types
Treatment
- Surgery - all or most of the tumour should be removed surgically if possible
- Shunting procedures relieve intracranial pressure if necessary
- Radiation is essential for all patients
- Chemotherapy - recommended for children when a tumour is large or has already spread
II. Malignant Tumours of the Brain: Metastatic
i. Metastatic Carcinoma
- Spread of tumours to the brain occurs most often from carcinoma of lung and breast
- Less frequently spread from kidney, bowel or stomach, melanoma
- Management depends on general condition of patient and whether metastases are solitary or multiple
- Solitary: surgery may be deemed appropriate followed by post-operative radiation; for inoperable lesion, stereotactic radiation may be indicated
- Multiple: radiation is the primary treatment - decadron is also often used
ii. Meningeal Carcinomatosis
- Spread of a metastatic cancer over the surface of the brain
- Results in confusion and a variety of neurological symptoms
- Not easily diagnosed unless abnormal cells are found during analysis of spinal fluid or on CT scan, or MRI imaging
III. Primary Benign Tumours
i. Acoustic Neuroma
General Information/ Anatomy/ Function/ Statistics
- Most common of several tumours that originate in the specialized cells that form the protective sheaths of nerve fibres
- Benign tumour but its steady growth puts pressure on and deforms adjacent brain structures
- Involves the nerve leading from the inner ear to the brain
- Seen most often in middle aged women
Symptoms/ Signs
- Tumour pressure affects walking, movement and balance
- Deafness
- Ringing in the ear
- Dizziness and vertigo
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading / Types
- Routine physical and neurological examination
- Testing of hearing
- MRI scan
Treatment
- Surgery is the major method of treatment
- Stereotactic radiotherapy can be used for initial treatment of small tumour or small recurrences after surgery
ii. Meningiomas
General Information/ Anatomy/ Function/ Statistics
- Tumours arise from the meninges, the fibrous tissues that cover the brain`s surface and spinal cord Accounts for 19% of all primary brain tumours
- Benign except for a few unusual instances that undergo malignant transformation
- More common in women and incidence rises steadily with age, beginning in middle adulthood
- Can develop from the meningeal layer anywhere but most common locations are over the surface of the brain and near the bone structure at its base
- Tumours cause displacement of normal brain structures
- Enlarges slowly
Symptoms/ Signs
- Seizures are common
- Symptoms depend on location in brain
Etiology/ Carcinogens/ Risks
- Some neurologists have suggested a possible connection between head injury and meningioma - most experts disagree
- Have been observed after cranial radiation
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Staging/ Grading/ Types
- Skull x-ray may show evidence of erosion of bone, presumably from tumour pressure
- CT scanning; MRI scanning more useful when tumour arises from the skull base
Treatment
- Surgery is the principal therapy
- Post operative radiation may be used for residual/ recurrent disease after surgery
- Radiation or repeat surgery are indicated for recurrent growth
- Chemotherapy is not used except in investigational or experimental study
iii. Pituitary Adenomas
General Information/ Anatomy/ Function/ Statistics
- 10% of intracranial tumours
- Pituitary gland is located near the base of the brain and consists of two sections: anterior and posterior
- Anterior pituitary secretes hormones into the bloodstream that regulates other endocrine glands: instrumental both in growth and metabolism
- Posterior pituitary secretes hormones which controls water retention and smooth muscle contraction
- Tumours are benign, slow-growing, encapsulated lesions
- There may be encroachment on adjacent structures causing pressure on the optic nerve
- Hormonal imbalances depend on its particular cell type, or by pressure on the normal pituitary
- An excess of prolactin hormone leads to impotence in men and excessive lactation in women
- An excess of growth hormone can lead to an enlarged heart, growth of the hands and feet and a change in facial features (acromegaly)
- The normal gland may be hyperactive or hypoactive
Symptoms/ Signs
- Frontal headaches
- Decreased visual acuity
- Possible cranial nerve palsies, especially affecting the eyes
- Symptoms related to hormonal imbalance:
- Acromegaly due to high levels of growth hormone
- Cushing's Disease due to excessive steroid hormone
- Decreased activity of the thyroid gland because of decreased secretion of the thyroid stimulating hormone
- (TSH) or acceleration of metabolic processes due to elevated thyroid hormone
- Abnormal libido or menstruation or lactation (prolactinoma)
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading / Types
- See Diagnosis section under general section of Central Nervous System
- X-rays of skull with attention to the pituitary area
- Precise examination of the patient`s field of vision
- CT scans and/or MRI
- Blood hormonal studies
Treatment
- Treatment is complex
- Aim is to reduce hyperfunction in hormone-secreting tumours and decompress the tumour
- Drug management may be adequate treatment, especially in prolactinomas and acromegely
- Surgical treatment, either via the skull or through the back of the nose, may be performed to stop over-secretion of hormones and to prevent blindness
- Radiation therapy may be recommended, especially for non-secreting tumours or secreting tumours - not adequately treated by medications
- Hormonal imbalance must be corrected and replacement programs have been well defined
- Lifelong hormonal therapy may be required after surgery and/or radiotherapy
iv. Craniopharyngiomas
General Information/ Anatomy/ Function/ Statistics
- Benign tumours that occur in the area of the pituitary gland
- Account for about 5% of primary brain tumours
- Commonly appear in childhood
- Do not affect the ability to secrete hormones
Symptoms/ Signs
- Symptoms result from pressure of the tumour on the pituitary gland and by extension into adjacent areas
Etiology/ Carcinogens/ Risks
- Thought to be remnants of structures that inappropriately remained in place after embryonic development
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Screening/ Staging/ Grading/ Types
- See Diagnosis section under general section of Central Nervous System
Treatment
- Craniopharyngiomas can sometimes be cured by neurosurgery
- Blockage of flows of C.S.F. may necessitate shunting
- Radiation is used for incompletely removed tumours
v. Pineal Gland Tumours
General Information/ Anatomy/ Function/ Statistics
- Pineal gland is a tiny structure that is located near the center of the brain
- It is believed that its function is to act as a biological clock and exert some influence over other glands
- Different kinds of benign tumours are known to develop in this gland; also may be malignant in nature
- Rare-accounting for less than 1% of all brain tumours
- Develop in children and young adults
- Tumour may affect the nerve centre that controls upward movement of the eyes
Symptoms/ Signs
- Movement disorders
- Mental deterioration
- Patients may be unable to look up because of involvement of nerve centre
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Staging/ Grading/ Types
- CT or MRI
- Tumour markers: blood tests may be helpful in certain tumours of the pineal region
- See Diagnosis section under general section of Central Nervous System
Treatment
- Surgery, although technically difficult because of the tumour's relatively inaccessible location, is now more frequently successful in achieving cure
- Radiation is effective in shrinking many of these tumours and may be curative
- Shunting may be necessary
Spinal Cord Tumours
General Information/ Anatomy/ Function/ Statistics
- The spinal cord is encased in the vertebral column extending from the base of the skull to the lower back
- May be afflicted by benign, malignant, or metastatic tumours
- Most tumours grow slowly but rapid progression of symptoms is a neurological emergency that unless treated can lead to permanent loss of function below the tumour in 12 to 24 hours
- Metastatic tumours most often spread to the vertebral column and have neurological effects when there is pressure on the spinal cord
- About 35% are benign and potentially curable
- Patients with spinal cord gliomas do poorly
- About 15% of spinal cord tumours are meningiomas affecting the protective covering of the cord
Symptoms/ Signs
- Symptoms are created by the compression of the spinal cord or the nerve roots by the enlarging tumour
- Pain: localized back pain or radiating pain
- Loss of sensation or paralysis
- Incontinence
Prevention
- There are no useful prevention or screening measures in healthy people
Diagnosis/ Staging/ Grading/ Types
- History and physical examination
- X-rays of the spine
- CT scans / MRI
- Lumbar puncture performed in conjunction with a myleogram (less common)
Treatment
- Steroids are administered to reduce the edema and swelling
- Surgery and radiation are the only treatment options for cord decompression
- Advances in surgery, e.g, microsurgery, and the use of lasers and electric coagulation, have increased the percentage of patients who achieve satisfactory results
- With metastatic tumours, both surgery and radiation are useful in preventing paralysis and incontinence
- Local radiation alone can relieve the pain and many of the symptoms of metastatic tumours
- For radiosensitive tumours (myeloma, lymphoma, oat cell carcinoma, tumours of the lung to the spine) radiation is the treatment of choice
- Surgery can be very successful in treating meningiomas if the important nerve tracks within the cord can be preserved
Research
BC Cancer Agency research activities in brain tumours are supported, in part, by the BCCA Neuro Oncology Research Fund. This fund is a result of generous donations from patients, their families and friends. Contact: Dr. Roy Ma (604) 877-600 local 2652 CNS Tumour Group Chair.
Photodynamic therapy is being used for the treatment of certain brain tumours, but only at St. Michael`s Hospital in Toronto. Dr. P.J. Muller, the physician responsible, can be reached at (416) 864-5590. The patient's family physician or specialist should call.
March 2007 We are currently reviewing and updating these pages. If you have any questions about your cancer and its treatment, please discuss with your oncologist or physician. Thank you.