Glioblastoma ( affecting the ) A guide for journalists on and its treatment Contents Overview Section 1 Glioblastoma Section 2 Epidemiology and prognosis Section 3 Treatment References

Contents

Contents 2 Overview 3 Section 1: Glioblastoma 4 i. About the brain 5 ii. What is brain cancer? 5 iii. Causes and risk factors 5 iv. Symptoms 5 v. Diagnosis 6 Section 2: Epidemiology and prognosis 7 i. Incidence & mortality 7 ii. Prognosis 7 Section 3: Treatment 8 i. 8 ii. Radiotherapy 8 iii. 8 iv. Biological (targeted) therapy 8 References 9

2/ 9 Contents Overview Section 1 Glioblastoma Section 2 Epidemiology and prognosis Section 3 Treatment References

Overview Glioblastoma (GBM) is a devastating disease for Worldwide, there are an estimated GBM progresses rapidly and patients can 240,000 cases of brain and nervous system deteriorate quickly. Common symptoms both patients and caregivers. It is the most aggressive tumours per year – GBM is the most include , , , common, and the most lethal, of these weakness, paralysis and personality or primary brain tumour – a tumour that originates in tumours.3 The treatment a patient receives cognitive changes such as losing the ability the brain – and despite available therapies, prognosis depends on the location of the tumour to speak or think clearly.4 Unfortunately, in the brain and their overall health and most patients ultimately lose their life to is extremely poor. The majority of patients do not age, but the current standard of care for GBM; therefore, maintaining optimal quality GBM is surgery followed by treatment of life is very important to patients and their survive for more than two years following diagnosis, caregivers and is a significant consideration with both chemotherapy and radiotherapy, 1 when selecting potential treatment options. and the median survival is generally less than a year. after which patients continue with The average 5-year survival rate is less than 3%.2 chemotherapy alone. Biological therapies This guide provides an overview of (also called targeted therapies) are a glioblastoma, including its incidence, relatively new approach to GBM treatment risk factors, symptoms, diagnosis and and have shown promise in clinical trials. treatment options.

3/ 9 Contents Overview Section 1 Glioblastoma Section 2 Epidemiology and prognosis Section 3 Treatment References

Section 1 Glioblastoma

The brain has two main types of cells; i. About the brain Figure 1 Anatomy of the brain and glial cells.6 Neurons act as Along with your , the brain makes ‘messenger’ cells, relaying and transmitting up your body’s signals from the body to the regions of the Glial cells (CNS), which controls and regulates body brain where they are processed. Neurons functions and processes – from what we are highly specialised cells that process think to how we move. The can and transmit information throughout the be divided into a number of distinct regions nervous system by electrical and chemical based on anatomy, structure or the activities signaling.6 Glial cells provide support controlled by the region (see Figure 1). for the neurons and help to regulate the signal transmission (from the word glial • The forebrain consists primarily of the meaning ‘glue’ in Greek). It is estimated cerebrum, which is the largest part of the that there are 10 times as many glial cells brain and controls thoughts and speech. Brain stem as neurons in the nervous system.6 • Situated at the back of the brain underneath the cerebrum is the Cells in the brain are protected from the Spinal cord cerebellum. The cerebellum is the second body’s circulating bloodstream by the blood largest region of the brain, controlling brain barrier (BBB), a network of tightly voluntary movement and balance. joined specialised cells that form the wall of • The connects the cerebrum the capillary and an additional layer outside to the spinal cord and consists of the the capillary. The vast majority of drugs midbrain, pons and medulla oblongata. (such as monoclonal antibodies) cannot The brainstem is associated with cross an intact BBB.7 However, the BBB involuntary functions, such as breathing is thought to be impaired in GBM, which and swallowing.5 may allow some drugs that are larger in molecular size to enter the brain.

4/ 9 Contents Overview Section 1 Glioblastoma Section 2 Epidemiology and prognosis Section 3 Treatment References

ii. What is brain cancer? a highly aggressive, fast-growing cancer leukaemia. The syndrome is thought • Increased (pressure and treatment is often limited by the to arise from in a build-up in the head) manifesting as Cancer is the term used to describe a tumour location and the ability of a patient which plays a role in tumour headaches, nausea and variety of diseases in which cells escape to tolerate surgery. Consequently, it is a suppression.14 the control mechanisms that normally limit • Cognitive impairment or slowing of particularly difficult cancer to treat.12 growth and division.8 Primary brain tumours • Radiation: Evidence suggests that cognitive function (e.g. losing the ability are caused by the uncontrolled replication exposure to ionising radiation (for to speak or think clearly) iii. Causes and risk factors and growth of cells originating in the brain. example, previous radiotherapy to • Changes in personality, mood or They can develop in both neuron and glial GBM generally occurs spontaneously and the head or working in the nuclear concentration without an identifiable cause, however, cells. (cancer developing from glial industry) may increase the risk of • Visual impairment certain factors have been linked to an developing GBM.15 cells) is the most common type of primary • Seizures increased risk of developing the disease: brain tumour (a tumour that originates in • Other factors: There has been much • Motor dysfunction such as paralysis the brain), accounting for approximately • Age: Although GBM can occur at any speculation over a link between mobile • Sensory loss e.g. numbness, weakness one third of all cases diagnosed. Glioma age, including in infants and children, phone use and brain tumours and many also represents approximately 80% of all the risk increases with age – the average studies have found conflicting results. 9 The symptoms of GBM are often distressing primary malignant brain .9 age at diagnosis is 64 years. No definitive association between the to patients and their caregivers as they • Gender: GBM is more frequently two has yet been found. The long- significantly and negatively impact on Glioblastoma (formerly glioblastoma diagnosed in men, though the reason for term risks of mobile phone use remain quality of life as well as ability to carry out multiforme; GBM) is the most common and this is unknown.10 unknown.16-18 activities of daily living. Because of this, most aggressive type of glioma.9 GBM is • Genetics: There is an increased symptom management can be as important often located in a region of the forebrain iv. Symptoms incidence of GBM in families with a as treatment of the disease. known as the cerebrum, which controls very rare hereditary disorder called Li- As GBM is an aggressive disease that some of the most advanced processes Fraumeni syndrome (LFS), the incidence progresses rapidly, patients can such as speech and emotions.6,10 While and prevalence of which is unknown.13 deteriorate quickly. The symptoms of GBM GBM is highly locally invasive (invading Patients with LFS are susceptible to a can vary depending on the size and location normal brain ), it rarely spreads to variety of different cancers, including of the tumour in the brain. The following are other organs beyond the brain. GBM is brain cancer, and common symptoms:10,19-21

5/ 9 Contents Overview Section 1 Glioblastoma Section 2 Epidemiology and prognosis Section 3 Treatment References

v. Diagnosis according to the presence of certain criteria, such as growth rate and cell If patients present symptoms that suggest differentiation (how ‘normal’ a cell looks a brain tumour, they usually undergo under a microscope). a Magnetic Resonance Imaging (MRI) scan, which produces a detailed picture • Grade I tumours are slow growing, of the brain, enabling any abnormalities to non-malignant and are associated with be seen.22 long-term survival

Diagnosis is confirmed by a , where • Grade II tumours are slow growing but sample tissue is taken from the suspected generally return more frequently than lesion.23 Biopsy of a brain tumour must be grade I tumours undertaken with caution to limit damage to • Grade III lesions are malignant, fast normal brain function. growing and poorly differentiated • Grade IV tumours are the fastest Brain tumour classification and is growing, highly malignant and are poorly defined by the World Health Organization differentiated. (WHO) classification of nervous system tumours.24 There are four grades of brain GBM is classified as a grade IV brain tumours which are classified on a scale tumour.24,25

6/ 9 Contents Overview Section 1 Glioblastoma Section 2 Epidemiology and prognosis Section 3 Treatment References

Section 2 Epidemiology and prognosis i. Incidence and mortality Figure 2 Incidence and mortality of some of the Figure 3 Comparing 5-year survival rate of GBM to other cancers worldwide Worldwide, there are an estimated 240,000 most common cancers worldwide cases of brain and nervous system tumours per year – GBM is the most common, and Scale 3 the most lethal, of these tumours. In the 500,000 1,000,000 1,500,000 1,750,000 US alone, approximately 18,000 people Incidence Mortality are diagnosed with GBM every year. GBM Brain, nervous system accounts for 13,000 cancer deaths in the US 238 annually.26 In most European countries, new 175 cases of GBM occur in approximately 2-3 Breast 1384 Overall 5-year survival rate for patients Overall 5-year survival rate for breast 27 people in every 100,000 each year. 459 with GBM: Less than 3% cancer patients: Up to 89%

Colorectal Source WHO GLOBOCAN 2008 Source American Cancer Society, Breast Cancer Facts and Figures 2009-2010. Atlanta, American Cancer Society, Inc. 1235 ii. Prognosis 609 Cancer statistics often use an ‘overall Lung However, the prognosis of GBM does vary 5-year survival rate’ to give a better idea 1608 1377 depending on the age of the patient, the of the longer term outlook for people with Stomach tumour size and location, the amount of a particular cancer. It is almost impossible 989 737 tumour that can be removed during surgery to predict how long an individual patient Liver and the neurological performance status might live, but 5-year survival rates can give 750 of the patient which may impact on their 696 an approximate range. As GBM is a ‘high treatment options (i.e. the ability for patients Source WHO GLOBOCAN 2008 grade’ and advanced disease, the average to live a ‘normal’ life and carry out day-to- 5-year survival rate for patients is particularly day tasks).24 poor, at less than 3%.2 The majority of GBM patients do not live over a year.24

7/ 9 Contents Overview Section 1 Glioblastoma Section 2 Epidemiology and prognosis Section 3 Treatment References

Section 3 Treatment

Treatment options for GBM vary depending or resection. Due to the sensitive nature iii. Chemotherapy iv. Biological (targeted) on a number of factors – tumour size, of the operation it is very rare that the Although chemotherapy has shown therapy position, whether it has spread to other entire tumour is removed during limited success in the treatment of GBM, Biological (targeted) therapies are a regions of the brain and the performance surgery, however, the greater the amount of the combination of radiotherapy and relatively new approach to cancer treatment status of the patient. The current standard tumour that can be removed, the better the chemotherapy is the established standard and target specific biological processes of care for GBM is surgery, chemotherapy prognosis for the patient.28 of care in patients with newly diagnosed that are often essential to tumour growth. and radiotherapy.28 More recent treatments GBM.1 Chemotherapy does not distinguish Biological therapy can include use of are biological (targeted) therapies, which Depending on the health and age of the between normal healthy cells and cancer monoclonal antibodies, vaccines and gene can be used alone or in combination with patient, surgery is usually followed by cells, which can lead to unwanted side therapies. As biological therapies precisely chemotherapy or radiotherapy. radiotherapy and chemotherapy followed effects. target cancer-specific processes, they may by maintenance chemotherapy treatment be less toxic to non-cancerous, healthy Arguably the most important factor of GBM to control the tumour or prevent tumour Unfortunately, in almost all cases, GBM cells than other types of treatment (such treatment is the physical, emotional and regrowth.28 will return or progress following treatment as chemotherapy and radiotherapy).33 psychological support a patient receives, as (known as recurrent disease). Some GBM is such an aggressive disease which Radiotherapy ii. patients will undergo second surgery can severely affect a patient’s quality of life. Along with surgery, radiotherapy is routinely or a second course of radiotherapy or given to patients with the aim of controlling chemotherapy. Prognosis at this stage Surgery i. tumour growth, reducing the chance of remains extremely poor32 and patients If the tumour is located in a part of the the cancer coming back (recurring) and sometimes consider participating in 28, 30 brain where it can be removed without alleviating symptoms. In cases where clinical trials.30 risking damage to the brain itself or surgery is inadvisable due to risk of damage subsequent brain function, then surgery to the brain, radiotherapy is recommended will typically be undertaken to remove as as a primary treatment and is widely much of the tumour as possible.29 This accepted as the standard of care.31 procedure is known as debulking surgery

8/ 9 Contents Overview Section 1 Glioblastoma Section 2 Epidemiology and prognosis Section 3 Treatment References

References

1 Stupp R et al. N Engl J Med (2005) 352:987-96 8 Hanahan D, Weinberg RA. Hallmarks of Cancer: The Next 17 Cardis E et al. Int. J Epidemiol (2010) 39(3):675-694 27 Piccirilli M Tumori (2005) 91:256-260 2 WHO, IARC, Globocan World Cancer Report (2003): Generation. Cell (2011) 144, March 4 18 National Cancer Institute: Cell phones and cancer risk. Last 28 Weller M. Swiss Med Wkly (2011) May 24;141:w13210 Human cancers by organ site 9 Central Registry of the United States accessed June 2012 at http://www.cancer.gov/cancertopics/ 29 Stupp R et al. Ann Oncol (2007) 18 (supplement 2):ii69– 3 WHO, IARC, Globocan Cancer Incidence and Mortality (CBTRUS): Primary Brain Tumours in the United States factsheet/Risk/cellphones ii70 Statistical Report Worldwide in 2008. Last accessed June 2012 at http:// 19 National Cancer Institute: Brain Tumor Treatments. Last 30 Medscape Reference: Neurologic Manifestations of globocan.iarc.fr/ 10 Medscape: Glioblastoma Multiforme. Last accessed June accessed June 2012 at http://www.cancer.gov/cancertopics/ Glioblastoma Multiforme Workup. Last accessed June 4 J Glass, Practical Neurology (2009): Glioblastoma 2012 at http://emedicine.medscape.com/article/283252- pdq/treatment/adultbrain/patient/ 2012 at http://emedicine.medscape.com/article/1156220- Multiforme: Current Treatment Options and Future overview 20 Reardon DA, Wen PY. The Oncologist (2006) 11(2):152- workup#showall Directions 11 Rodrigues Alves T et al. Life Sciences (2001) 89(15– 164 31 National Brain Tumor Society: Understanding 5 American Association of Neurological Surgeons. Anatomy 16):532-539 21 Cheng J-x. Neuro Oncol (2009). 11(1):41-50 Glioblastoma. Last accessed June 2012 at http://www. of the brain. Last accessed June 2012 at http://www.aans. 12 Holland EC. Proc Natl Acad Sci USA (2000) 97(12):6242- 22 Weller M. Swiss Med Wkly (2011) May 24;141:w13210 braintumor.org/patients-family-friends/about-brain- org/Patient%20Information/Conditions%20and%20 6244 tumors/publications/ 23 Stupp R, Roila F. Ann Oncol (2009) 20 (suppl 4):iv126- Treatments/Anatomy%20of%20the%20Brain.aspx 13 Hill DA. Cancer Epidemiol Biomarkers Prev (2003) iv128 32 Hou LC et al. Neurosurg Focus (2006) 20(4) American 6 New Scientist Introduction: The Human Brain. Last 12(12):1443-8 Association of Neurological Surgeons 24 Louis DN et al. Acta Neuropathol (2007) 114:97–109 accessed June 2012 at http://www.newscientist.com/article/ 14 Medscape: Li-Fraumeni Syndrome. Last accessed June 33 National Cancer Institute: Targeted cancer therapies. Last 25 National Cancer Institute: Classification of Adult dn9969-instant-expert-the-human-brain.html 2012 at http://emedicine.medscape.com/article/987356- accessed June 2012 at http://www.cancer.gov/cancertopics/ Brain Tumors. Last accessed June 2012 at http://www. 7 UK: About brain tumour chemotherapy. overview#showall factsheet/Therapy/targeted cancer.gov/cancertopics/pdq/treatment/adultbrain/ Last accessed June 2012 at http://cancerhelp. 15 MedicineNet: Brain Tumor. Last accessed June 2012 http:// HealthProfessional/page2#Reference2.4 cancerresearchuk.org/type/brain-tumour/treatment/ www.medicinenet.com/brain_tumor/article.htm chemotherapy/about-brain-tumour-chemotherapy 26 Schwartzbaum JA. Nat Clin Practice Neurol (2006) 2:494- 16 Inskip PD et al. N Engl J Med (2001) 344:79-86 503

9/ 9