FACT SHEET: Brain Tumours (also known as “cerebral tumours”; includes benign and malignant tumours)
Note: Chemotherapy and Radiation Therapy, which are treatment modalities for some brain tumours, are specifically addressed in more detail in separate fact sheets. Epilepsy (seizure disorder), which results from some brain tumours, is also addressed in a separate fact sheet. This fact sheet focuses on the specific idiosyncrasies of brain tumours. [More detailed information on brain tumours can be found in the CDHO Advisory on Brain Tumours.]
Is the initiation of non-invasive dental hygiene procedures* contra-indicated?
- Yes, if increased intracranial pressure or other sequelae of the brain tumour manifest as signs (e.g., vomiting, decreased gag reflex, uncontrolled seizures, etc.) potentially incompatible with oral procedures.
- Possibly, if patient/client has recently undergone brain surgery.
- Possibly, if patient/client is receiving radiotherapy.
- Possibly, if patient/client is receiving chemotherapy.
Is medical consult advised?
- Yes, if a previously undiagnosed brain tumour is suspected (likely primary care physician consult) or the patient/client’s condition is unstable or deteriorating (likely neurosurgeon or emergency physician consult).
- Yes, if the patient/client has recently undergone or will soon undergo brain surgery.
- Yes, if patient/client is about to undergo, is undergoing, or has recently undergone radiotherapy.
- Yes, if patient/client is about to undergo, is undergoing, or has recently undergone chemotherapy.
Is the initiation of invasive dental hygiene procedures contra-indicated?**
- Yes, if increased intracranial pressure or other sequelae of the brain tumour manifest as signs (e.g., vomiting, decreased gag reflex, uncontrolled seizures, etc.) potentially incompatible with oral procedures.
- Yes, if patient/client is receiving corticosteroid therapy (e.g., for management of cerebral edema or to minimize risk of side-effects and encephalopathy from radiotherapy), which may be associated with immunosuppression +/- increased risk of infection.
- Yes, if patient/client is about to undergo, or has recently undergone, brain surgery.
- Yes, if patient/client is receiving radiotherapy.
- Yes, if patient/client is receiving chemotherapy.
Is medical consult advised?
- As above.
- Yes, if there is medication non-compliance for seizure disorder.
Is medical clearance required?
- Yes, if patient/client is about to undergo, or has recently undergone, brain surgery.
- Yes, if radiotherapy or chemotherapy is underway or planned for the near future.
- Yes, if there is significant risk of seizure.
- Possibly, if patient/client is being treated with corticosteroids (e.g., dexamethasone, prednisone, etc.).
Is antibiotic prophylaxis required?
- Possibly, but uncommonly, for radiotherapy to the head/brain.
- Possibly, for chemotherapy.
- Possibly, for corticosteroid use.
Is postponing treatment advised?
- Yes, if increased intracranial pressure or other sequelae of the brain tumour manifest as signs (e.g., vomiting, decreased gag reflex, uncontrolled seizures, etc.) potentially incompatible with oral procedures.
- Possibly, if patient/client is about to undergo, or has recently undergone, brain surgery.
- Possibly, for radiotherapy to the head/brain.
- Possibly, for chemotherapy.
- Possibly, for corticosteroid use.
Oral management implications
- Dental hygiene treatment planning for the patient/client with a brain tumour begins with establishing the diagnosis (i.e., primary brain cancer vs. metastatic brain cancer vs. benign tumour). Planning involves pre-therapy evaluation (e.g., is the patient/client to receive therapeutic/potentially curative treatment or palliative therapy) and preparation of the patient/client; oral healthcare during tumour therapy (including hospital and outpatient care); and post-therapy management. Tumours that can be surgically addressed and do not affect the oral cavity require few treatment modifications. However, brain cancers requiring chemotherapy affect oral health due to immunosuppression.
- A pre-therapy oral evaluation should occur for all cancer patients/clients before (typically a month) the initiation of cancer therapy to: rule out disease that may be exacerbated during cancer therapy; provide a baseline for comparison and monitoring of chemotherapy and radiation damage; detect metastatic lesions; and minimize oral discomfort during cancer therapy.
- Pre-therapy care should include oral hygiene instruction, education about a noncariogenic diet, calculus removal, prophylaxis and fluoride treatment, and elimination of sources of oral irritation and infection.
- Dental x-rays should be used sparingly to reduce radiation risk to all patients/clients, and thereby reduce risk of radiation-induced tumours (including brain). Fast speed film or digital imaging can reduce radiation exposure.
Oral manifestations
- Facial weakness (resulting in lip drooping, drooling, etc.) may be caused by brain tumours.
- Seizures resulting from brain tumours can cause biting of the tongue and cheeks, as well as chipping of the teeth. Furthermore, anticonvulsant medications can have numerous oral manifestations.
- Vestibular schwannomas1 can manifest as a toothache and/or numbness in the orofacial area.
- Complications of systemic chemotherapy and radiation therapy to the head include mucositis; infection (including candidiasis); xerostomia and salivary gland dysfunction; impaired ability to eat, taste, swallow and speak; and abnormal tooth development and craniofacial growth in children.
- Chemotherapy can cause neurotoxicity (manifesting as persistent aching or burning pain that mimics a toothache) and bleeding (due to decreased platelets and clotting factors associated with depression of bone marrow function).
- Radiotherapy to the head, which generally affects only cells in the path of the radiation, may cause scarring of oral tissue. Osteoradionecrosis may occur where bone is exposed to radiation; most cases occur in the mandible, where vascularization is poor and bone density is high. Radiation caries and trismus/tissue fibrosis are other complications.
- Oral candidiasis and other oral infections can result from corticosteroid management of brain tumours, which leads to immunosuppression.
- Xerostomia may result from certain antiemetic/anti-nausea medications.
Related signs and symptoms
- About 55,000 Canadians live with a brain tumour, and 27 Canadians are newly diagnosed each day.
- There are more than 120 types of brain tumours. They are classified as either primary tumours (which arise in the brain, and may be either benign2 or malignant3) or secondary tumours (which are metastases from malignant tumours originating elsewhere in the body). Primary brain tumours are also classified by grade (I, II, III, or IV) according to how abnormal the cancer cells appear microscopically and how quickly they are likely to grow and spread.
- Primary brain tumours are named according to the type of cells they comprise (e.g., germ cells, glial4 cells, or neurons) or the area of the brain or nearby nerves from which they arise.
- Primary benign brain tumours5 include meningiomas (which tend to grow slowly, are the most common primary brain tumours in adults, and have been controversially linked to cumulative dental x-ray exposure by some researchers); vestibular schwannomas (which arise in the nerves responsible for balance and hearing); and craniopharyngiomas (which occur most often in children). Benign (i.e., non-malignant) tumours account for almost two-thirds of primary brain tumours.
- Primary brain and nervous system tumours are relatively uncommon in adults, with brain metastases from distant body sites being much more common. However, in children primary brain tumours are relatively more common. Brain tumours are the leading cause of solid cancer death in children under the age of 20 years, and the third leading cause in adults aged 20 to 39 years.
- Primary malignant brain tumours include astrocytomas (such as fast-growing glioblastomas, which occur mostly in middle-aged to older adults); medulloblastomas (which are the most common brain tumours in children); oligodendrogliomas (which usually grow slowly); brain stem gliomas (which occur mostly in children and young adults); and ependymomas (which occur most commonly in children and young adults).
- Germ cell tumours of the brain may be either benign or malignant, and they typically occur before the age of 30 years. Incidence rates are higher in persons of Asian descent.
- Secondary (i.e., metastatic) brain tumours typically originate from the lung (up to 50% of metastatic brain tumours), breast, colon, kidney, nasopharynx, bladder, testes, or skin (i.e., melanoma). Such cancers usually occur in the cerebrum (and less frequently in the cerebellum or brain stem) as multiple tumours, and they are most common in persons who are middle-aged or elderly. Cancers such as leukemia and lymphoma may also spread to the leptomeninges6. Metastatic brain tumours occur at some point in 20% to 40% of persons with cancer, and incidence is increasing as persons with cancer live longer.
- Signs and symptoms of brain tumours vary according to the tumour type, size, and location. They may be associated with pressure of the tumour on adjacent brain/neural tissue, swelling of the brain, and fluid build-up in the brain. Malignant brain tumours are often life threatening.
- Brain tumours, whether benign or malignant, can cause the following signs and symptoms: headaches (particularly those of recent onset and unusual character, including morning headache relieved by vomiting); nausea and vomiting (particularly in the morning); fatigue and unusual sleepiness; changes in vision, hearing, and/or smell; changes in behaviour, personality, and/or cognition (including memory, concentration, and speech); balance and walking problems; numbness or weakness of a body area (including the face or a limb); and seizures. In infants, hydrocephalus7 (increase in head size) may occur, along with bulging of the fontanelle, high-pitched crying and irritability.
- Craniopharyngiomas, given their proximity to the pituitary gland and hypothalamus, may cause delayed development in children, weight gain, and excessive thirst and urination.
- Treatment of brain tumours with surgery can result in personality and cognition changes, as well as neurological deficits such as numbness, weakness, or paralysis.
- Treatment of brain tumours with cranial radiation therapy can cause necrosis of healthy brain tissue with consequent headaches, seizures, or death. Headaches may also result from post-treatment edema of the brain. Damage to the pituitary gland can result in hypopituitarism, leading to failure of growth (in children; due to low growth hormone); low blood glucose and low sodium levels (due to low adrenocorticotropic hormone); low libido (due to low sex hormones); weight gain, fatigue, and feeling cold (due to low thyroid hormone); and excessive thirst and urination (due to low antidiuretic hormone).
- Prognosis for patients/clients with brain tumours varies widely depending on tumour type, size, location, and grade; patient/client age and response to treatment; and presence of comorbidities and complications. In children, survival rates have increased substantially given advances in treatment, and up to 60% of children with brain tumours will survive, albeit often with long-term side effects. By contrast, mean life expectancy for persons diagnosed with secondary brain tumours until recently was about 1 month without radiation therapy and 4 to 6 months with radiation therapy; somewhat longer survival rates since the late 2000s have increasingly entailed neurosurgical intervention for brain metastases.
References and sources of more detailed information
- CDHO Advisory Knowledge Network
https://cdho.org/advisories/brain-tumours/ - Lam R. Acoustic neuroma manifesting as toothache and numbness. Australian Dental Journal. 2016 Mar;61(1):109-112.
https://onlinelibrary.wiley.com/doi/10.1111/adj.12302 - Auvinen A, Cardis E, Blettner M et al. and the INTERPHONE study group. Diagnostic radiological examinations and risk of intracranial tumours in adults—findings from the Interphone Study. International Journal of Epidemiology. 2022 Apr;51(2):537-546.
https://academic.oup.com/ije/article/51/2/537/6397012 - Hancock PJ, Epstein JB, Sadler GR. Oral and Dental Management Related to Radiation Therapy for Head and Neck Cancer. J Can Dent Assoc 2003;69(9):585-90.
https://cda-adc.ca/jcda/vol-69/issue-9/585.pdf - Samim F, Epstein JB, Zumsteg ZS et al. Oral and dental health in head and neck cancer survivors. Cancers Head Neck. 2016;1(14). doi:10.1186/s41199-016-0015-8
https://cancersheadneck.biomedcentral.com/articles/10.1186/s41199-016-0015-8 - Lehrer S, Green S, Rosenzweig KE. Lack of Correlation between Benign Brain Tumors and Markers of Oral Health. N Y State Dent J. 2015 Apr;81(3):41-3.
https://pubmed.ncbi.nlm.nih.gov/26094363/ - Dietrich J, Rao K, Pastorino S, Kesari S. Corticosteroids in brain cancer patients: benefits and pitfalls. Expert Rev Clin Pharmacol. 2011 Mar;4(2):233-242.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3109638/ - Giulioni M, Marucci G, Martinoni M et al. Epilepsy associated brain tumours: Review article. World J Clin Cases. 2014 Nov 6;(2)11:623-641.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4233414/ - Canadian Dental Association (“CD Alert” — Media Reports on Dental X-rays)
https://www.cda-adc.ca/en/about/media_room/canadian_dentistry_news/articles/2012/041012.asp - Canadian Dental Association (CDA Position on Control of X-Radiation in Dentistry)
https://www.cda-adc.ca/en/about/position_statements/xray/ - Brain Tumour Foundation of Canada
https://www.braintumour.ca
https://www.braintumour.ca/facing-a-brain-tumour/signs-symptoms/
https://www.braintumour.ca/facing-a-brain-tumour/brain-tumour-types/ - National Cancer Institute
https://www.cancer.gov/types/brain/patient/adult-brain-treatment-pdq#section/all
https://www.cancer.gov/types/brain - National Institute of Dental and Craniofacial Research — Oral Complications of Cancer Treatment: What the Dental Team Can Do
https://www.nidcr.nih.gov/health-info/cancer-treatments (Cancer Treatments & Oral Health) - American Dental Association (“Oral Health News”)
https://www.oralhealthgroup.com/oral-health/american-dental-association-dental-x-rays-should-be-used-sparingly-to-reduce-radiation-risk-1001063860/ - WebMD
https://www.webmd.com/cancer/brain-cancer/brain-cancer?page=2 - Yale Medicine
https://www.yalemedicine.org/conditions/metastatic-brain-tumors/ - Yale School of Public Health
https://ysph.yale.edu/news-article/non-cancerous-brain-tumors-linked-to-frequent-dental-x-rays-1/ - National Health Service (U.K.)
https://www.nhs.uk/conditions/malignant-brain-tumour/ - Society for Endocrinology (U.K.)
https://www.yourhormones.info/endocrine-conditions/craniopharyngioma/
https://www.yourhormones.info/endocrine-conditions/hypopituitarism/ - Bowen DM (ed.) and Pieren JA (ed.). Darby and Walsh Dental Hygiene: Theory and Practice (5th edition). St. Louis: Elsevier; 2020.
- Little JW, Miller CS and Rhodus NL. Little and Falace’s Dental Management of the Medically Compromised Patient (9th edition). St. Louis: Elsevier Mosby; 2018.
- Ibsen OAC and Peters SM. Oral Pathology For The Dental Hygienist (8th edition). St. Louis: Elsevier; 2023.
FOOTNOTES
2 A benign (i.e., non-cancerous) tumour is comprised of cells that resemble the tissue from which it arises, is usually circumscribed and encapsulated, usually grows slowly, and does not metastasize. While benign brain tumours do not metastasize elsewhere in or from the brain, they are not necessarily harmless, because they can compress structures with the skull and increase intracranial pressure.
3 A malignant tumour (i.e., cancer or malignant neoplasm) is comprised of atypical or dysplastic cells that may not resemble the parent tissue. It not only infiltrates locally but also has the potential to metastasize or spread to distant sites. Malignant brain tumours may be primary (i.e., arising from brain tissue) or secondary (i.e., metastases arising from primary cancers elsewhere in the body, such as lung).
4 Glial cells are supportive cells that help neurons function, and they are the most common cellular component of the brain.
5 Benign brain tumours are usually treated surgically. However, chemotherapy and radiotherapy may be occasionally used to shrink a benign tumour or kill tumour cells left behind after surgery.
6 leptomeninges = the two innermost membranes covering the brain and spinal cord
7 Hydrocephalus is usually treated with surgical placement of a shunt system that drains excess cerebrospinal fluid (CSF) into another part of the body.
* Includes oral hygiene instruction, fitting a mouth guard, taking an impression, etc.
** Ontario Regulation 501/07 made under the Dental Hygiene Act, 1991. Invasive dental hygiene procedures are scaling teeth and root planing, including curetting surrounding tissue.