Neuro-oncology Lecture Notes PDF

Neuro-oncology Dr. Jose Sapien, MD. Lecturer The Definition of Cancer Cancer is a disease in which some of the body’s cells grow uncontrollably and spread to other parts of the body. These cells may form tumors, which are lumps of tissue. Tumors can be: cancerous or not cancerous. Cancerous tumors s...

Neuro-oncology Dr. Jose Sapien, MD. Lecturer The Definition of Cancer Cancer is a disease in which some of the body’s cells grow uncontrollably and spread to other parts of the body. These cells may form tumors, which are lumps of tissue. Tumors can be: cancerous or not cancerous. Cancerous tumors spread into, or invade, nearby tissues and can travel to distant places in the body to form new tumors (a process called metastasis). 2 (What Is Cancer? - NCI, 2021) “Hallmarks” of Cancer 3 Mazingi and Lakhoo, “Cancer Development and Progression and the ‘Hallmarks of Cancer.’” How Does Cancer Develop? Cancer is a genetic disease—that is, it is caused by changes to genes that control the way our cells function, especially how they grow and divide. Genetic changes that cause cancer can happen because: Random mutations Induced mutations Inheritance (Somatic cells?) 4 (What Is Cancer? - NCI, 2021) Chronic inflammation → normal cells are kept activated for tissue repair. Then they acquire the phenotype of the shifted homoeostasis and respond irreversibly to the continued inflammation → malignancy. N Engl J Med 2014; 371:836-845 DOI: 10.1056/NEJMra1314704 5 From: Intracranial Stereotaxic Cannulation for Development of Orthotopic Glioblastoma Allograft in Sprague-Dawley Rats and Histoimmunopathological Characterization of the Brain Tumor - Scientific Figure on ResearchGate. Available from: https://www.researchgate.net/figure/Histological-characterization-of-normal-brain-and-C6-brain-tumor-sections-Both-the_fig3_6139063 [accessed 26 Feb, 2024] 6 British Journal of Cancer (Br J Cancer) Risk factors Kayode, Abolanle & Amina, shahzadi & Akram, Muhammad & Hina, Anwar & Kayode, Omowumi & Omowunmi, Akinnawo & Okoh, Olayinka. (2020). Brain Tumor - An overview of the Clinical Manifestations and Treatment. 10.17352/gjct. 7 What is a brain tumor? There are more than 120 different types of tumors that can develop in the brain, depending on what tissue they arise from. 8 - oma suffix 1.(forming nouns) denoting tumors and other abnormal growths. 9 Tumor… or Cancer? Benign brain tumors: Grow slowly Have distinct borders Rarely spread. Benign tumor Can still be dangerous. Examples of typically benign tumors include meningioma and pituitary adenoma. 10 Tumor… or Cancer? Malignant brain tumors (Cancerous): They typically grow rapidly Invade other structures Some examples of malignant tumors that originate in or near the brain include olfactory neuroblastoma, chondrosarcoma and medulloblastoma. 11 Primary or Metastatic Brain Tumors? Primary brain tumors are tumors that start in the brain. Examples of tumors that most often originate in the brain include meningioma and glioma. Primary common cancers that can spread to the brain are: Breast cancer Colon cancer Kidney cancer Lung cancer Secondary/Metastatic brain tumors Skin cancer (melanoma) 12 Naming Brain Tumors Brain tumors can form in any part of the brain → The location can give name. Meningiomas: The meninges. Pituitary tumors: Pituitary gland. Medulloblastoma: The cerebellum or brainstem. Skull base tumors: From the skull base. Other brain tumors are described by the kinds of cells they are made of. For instance, gliomas are composed of ________?. 13 14 From: 2021 WHO classification of tumours of the central nervous system: a review for the neuroradiologist Source: Drawn from Louis DN, Perry A, Wesseling P, et al. The 2021 WHO Classification of Tumors of the Central Nervous System: a summary [published online ahead of print, 2021 Jun 29]. Neuro Oncol. 2021;noab106 15 Brain Tumors in Children Brain tumors are the most common solid tumor in children and adolescents, affecting about 5,000 children in the U.S. each year. 16 Brain Tumors in Adult Brain tumors account for 85% to 90% of all primary central nervous system (CNS) tumors. Worldwide: Approx. 308,102 new cases of brain and other CNS tumors were diagnosed in the year 2020 (251,329 deaths). 17 Primary Brain Tumors It includes the following in decreasing order of frequency: Anaplastic astrocytomas and glioblastomas (38% of primary brain tumors). Meningiomas and other mesenchymal tumors (27% of primary brain tumors). Pituitary tumors. Schwannomas. CNS lymphomas. Oligodendrogliomas. Ependymomas. Low-grade astrocytomas. Approximately 80% to 85% of malignant brain tumors in adults are gliomas, which diffusely infiltrate the brain parenchyma. WHO classification of tumors of CNS → group of tumors as adult-type diffuse gliomas. Medulloblastomas. 18 Astrocytoma grade IV, mostly known as glioblastoma multiforme (GBM), represents the most aggressive subtype of malignant brain tumour with a 12–16 month median overall survival (Stupp et al., 2005; Wen and Kesari, 2008). 19 Primary spinal tumors Primary spinal tumors include the following in decreasing order of frequency: Schwannomas, meningiomas, and ependymomas (79% of primary spinal tumors). Sarcomas. Astrocytomas. Vascular tumors. Chordomas. 20 Brain Tumor Symptoms They will vary depending on the tumor’s location. The tumor’s size and how fast it’s growing also affect symptoms. The most common symptoms of a brain tumor may include: Headaches 50% (Chronic and Loss of hearing morning/night preference) Vision changes Nausea Confusion and disorientation Seizures Memory loss Cognitive impairment Personality or behavior changes Weakness, numbness or paralysis Progressive and resistant Loss of balance, dizziness or unsteadiness 21 22 Brain Tumor Diagnosis Diagnosing a brain tumor usually involves a neurological exam, brain scans (Contrast-enhanced magnetic resonance imaging (MRI) of the brain), and a biopsy, if it can be done safely. Biopsy The sample is examined by a pathologist to identify an area of tissue with sufficient tumor for detection (>=50% tumor if possible). Genomic DNA is extracted from a blood or bone marrow specimen. The exons 4 and 5 of the IDH1 gene are captured and sequenced by next generation sequencing. 23 24 The following tests help to confirm the diagnosis if biopsy not possible: Lumbar puncture (contains traces of the tumor cells?) Evoked potentials studies to measure electrical activity in the nerves Electroencephalography (EEG) to measure electrical activity in the brain. Neurocognitive assessment Neuro-ophthalmological examination Endocrinological evaluation 25 Brain Tumor Grading The grade of a brain tumor defines how serious it is. Brain tumor grading uses a World Health Organization tumor grading system from 1 (least aggressive) to 4 (most aggressive). Is this staging? 5th or 6th edition? WHO classification of brain tumor grades, 2022 26 27 Treatment The following types of treatment are used: Active surveillance Surgery Radiation therapy Chemotherapy Targeted therapy Proton beam radiation therapy Immunotherapy 28 Extra Bibliography (Brain Tumors and Brain Cancer, https://www.hopkinsmedicine.org/health/conditions-and-diseases/brain-tumor) (What Is Cancer? - NCI, 2021) https://www.cancer.gov/about-cancer/understanding/what-is-cancer British Journal of Cancer (Br J Cancer) Adult Central Nervous System Tumors Treatment (PDQ®)–Health Professional Version, NIH: https://www.cancer.gov/types/brain/hp/adult-brain-treatment-pdq#_1 Neuro-oncology, BCCA; http://www.bccancer.bc.ca/healthprofessionals/clinical-resources/cancer-management-manual/neurooncology/neuro-oncology#Staging Brain Tumors and Brain Cancer, John Hopkins Medicine; https://www.hopkinsmedicine.org/health/conditions-and-diseases/brain-tumor 29