Achieve Mastery of Medical Concepts

Study for medical school and boards with Lecturio

Astrocytoma

Astrocytomas are neuroepithelial tumors that arise from astrocytes Astrocytes A class of large neuroglial (macroglial) cells in the central nervous system - the largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from 'star' cells) are irregularly shaped with many long processes, including those with 'end feet' which form the glial (limiting) membrane and directly and indirectly contribute to the blood-brain barrier. They regulate the extracellular ionic and chemical environment, and 'reactive astrocytes' (along with microglia) respond to injury. Nervous System: Histology, which are star-shaped glial cells Glial Cells The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the blood-brain barrier and blood-retinal barrier, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear. Nervous System: Histology (supporting tissues of the CNS). Astrocytomas are a type of glioma. There are 4 grades of astrocytomas. Grade I tumors are typically benign Benign Fibroadenoma and present in children, while grade IV tumors (known as glioblastoma multiforme Glioblastoma multiforme Glioblastoma multiforme is a high-grade astrocytoma, an aggressive brain tumor arising from astrocytes, with an unknown cause and a poorly understood link to risk factors. There are two main types: primary, a more aggressive form seen more commonly in older patients, and secondary, developing from lower-grade astrocytomas and seen more commonly in younger patients. Glioblastoma Multiforme) are the most common primary malignant brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tumor Tumor Inflammation in adults and have a particularly poor prognosis Prognosis A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas. The etiology of astrocytomas is usually unknown. The exact presenting symptoms depend on the tumor Tumor Inflammation location and grade, but patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship may exhibit headaches, seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures, and/or focal neurologic deficits Neurologic Deficits High-Risk Headaches. Diagnosis is made by MRI and tissue biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma. Treatment depends on the grade of the tumor Tumor Inflammation and may include any combination of surgery, radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma therapy, and/or chemotherapy Chemotherapy Osteosarcoma.

Last updated: Jun 13, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Overview

Definition

Astrocytomas are neuroepithelial tumors in the CNS arising from astrocytes Astrocytes A class of large neuroglial (macroglial) cells in the central nervous system – the largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from ‘star’ cells) are irregularly shaped with many long processes, including those with ‘end feet’ which form the glial (limiting) membrane and directly and indirectly contribute to the blood-brain barrier. They regulate the extracellular ionic and chemical environment, and ‘reactive astrocytes’ (along with microglia) respond to injury. Nervous System: Histology, a type of star-shaped glial cell.

  • Glial cells Glial Cells The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the blood-brain barrier and blood-retinal barrier, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear. Nervous System: Histology are supportive tissues within the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification and nervous system Nervous system The nervous system is a small and complex system that consists of an intricate network of neural cells (or neurons) and even more glial cells (for support and insulation). It is divided according to its anatomical components as well as its functional characteristics. The brain and spinal cord are referred to as the central nervous system, and the branches of nerves from these structures are referred to as the peripheral nervous system. Nervous System: Anatomy, Structure, and Classification.
  • Neuroepithelial tumors are those involving the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification parenchyma.
  • Astrocytomas are graded, but not staged.

Classification of nervous system Nervous system The nervous system is a small and complex system that consists of an intricate network of neural cells (or neurons) and even more glial cells (for support and insulation). It is divided according to its anatomical components as well as its functional characteristics. The brain and spinal cord are referred to as the central nervous system, and the branches of nerves from these structures are referred to as the peripheral nervous system. Nervous System: Anatomy, Structure, and Classification tumors

Table: Classification of nervous system Nervous system The nervous system is a small and complex system that consists of an intricate network of neural cells (or neurons) and even more glial cells (for support and insulation). It is divided according to its anatomical components as well as its functional characteristics. The brain and spinal cord are referred to as the central nervous system, and the branches of nerves from these structures are referred to as the peripheral nervous system. Nervous System: Anatomy, Structure, and Classification tumors
Categories Specific tumors
Neuroepithelial tumors in the CNS
  • Astrocytomas, including glioblastoma multiforme Glioblastoma multiforme Glioblastoma multiforme is a high-grade astrocytoma, an aggressive brain tumor arising from astrocytes, with an unknown cause and a poorly understood link to risk factors. There are two main types: primary, a more aggressive form seen more commonly in older patients, and secondary, developing from lower-grade astrocytomas and seen more commonly in younger patients. Glioblastoma Multiforme
  • Oligodendroglioma Oligodendroglioma Oligodendrogliomas are malignant CNS tumors arising from neural glial cell precursors. Oligodendrogliomas often arise in the frontal lobes of the brain and have a generally favorable prognosis when compared to other gliomas. Oligodendrogliomas are the 3rd most common CNS tumor. The most frequent presenting symptom is a seizure. Oligodendroglioma
  • Ependymoma Ependymoma Ependymomas are glial cell tumors arising from CSF-producing ependymal cells lining the ventricular system. Ependymomas most commonly occur within the posterior fossa in contact with the 4th ventricle, or within the intramedullary spinal cord. Ependymoma and choroid-plexus tumors
  • Medulloblastomas (embryonal tumors)
Meningeal tumors
  • Meningiomas
  • Hemangioblastomas Hemangioblastomas A benign tumor of the nervous system that may occur sporadically or in association with von Hippel-Lindau disease. It accounts for approximately 2% of intracranial tumors, arising most frequently in the cerebellar hemispheres and vermis. Histologically, the tumors are composed of multiple capillary and sinusoidal channels lined with endothelial cells and clusters of lipid-laden pseudoxanthoma cells. Usually solitary, these tumors can be multiple and may also occur in the brain stem, spinal cord, retina, and supratentorial compartment. Cerebellar hemangioblastomas usually present in the third decade with intracranial hypertension, and ataxia. Von Hippel-Lindau Disease
Sellar region tumors
  • Craniopharyngioma Craniopharyngioma Craniopharyngiomas are rare squamous epithelial tumors with a solid and/or cystic structure that arise from the remnants of Rathke’s pouch along the pituitary stalk, in the suprasellar region. Craniopharyngiomas are histologically benign but tend to invade surrounding structures; thus, they should be treated as low-grade malignancies. Craniopharyngioma
  • Pituitary Pituitary A small, unpaired gland situated in the sella turcica. It is connected to the hypothalamus by a short stalk which is called the infundibulum. Hormones: Overview and Types adenoma
  • Pinealoma/pinealoblastoma
Primary CNS lymphoma Lymphoma A general term for various neoplastic diseases of the lymphoid tissue. Imaging of the Mediastinum Primary CNS lymphoma Lymphoma A general term for various neoplastic diseases of the lymphoid tissue. Imaging of the Mediastinum
Metastasis Metastasis The transfer of a neoplasm from one organ or part of the body to another remote from the primary site. Grading, Staging, and Metastasis to the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification (5x more common than primary brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tumors) Most commonly arising from:
  • Lung, breast, and renal cell carcinomas
  • Melanoma Melanoma Melanoma is a malignant tumor arising from melanocytes, the melanin-producing cells of the epidermis. These tumors are most common in fair-skinned individuals with a history of excessive sun exposure and sunburns. Melanoma
Peripheral tumors
  • Schwannomas, including acoustic neuroma Acoustic neuroma Acoustic neuroma, also referred to as vestibular schwannoma, is a benign tumor arising from Schwann cells of the vestibular component of the cranial nerve VIII. Acoustic neuroma forms within the internal auditory meatus and extends into the cerebellopontine angle. Acoustic Neuroma
  • Neuroblastoma Neuroblastoma Neuroblastoma is a malignancy that arises from the neural crest cell derivatives along the sympathetic chain (neuroblasts) and is most commonly located in the adrenal medulla. The tumor often presents in childhood with a flank mass that crosses the midline. Neuroblastoma

Classification of astrocytomas

There are several classification systems for astrocytomas, but the most widely used is the WHO grading Grading Methods which attempt to express in replicable terms the level of cell differentiation in neoplasms as increasing anaplasia correlates with the aggressiveness of the neoplasm. Grading, Staging, and Metastasis system, which divides astrocytomas into 4 grades according to the extent of nuclear atypia Atypia Fibrocystic Change, mitotic activity, cellularity, vascular proliferation, and necrosis Necrosis The death of cells in an organ or tissue due to disease, injury or failure of the blood supply. Ischemic Cell Damage.

  • Grade I: noninvasive tumors that typically occur in children 
    • Pilocytic astrocytoma:
      • Well-circumscribed, slow-growing, cystic Cystic Fibrocystic Change tumors 
      • Usually arise in the cerebellum Cerebellum The cerebellum, Latin for “little brain,” is located in the posterior cranial fossa, dorsal to the pons and midbrain, and its principal role is in the coordination of movements. The cerebellum consists of 3 lobes on either side of its 2 hemispheres and is connected in the middle by the vermis. Cerebellum: Anatomy → may lead to compression Compression Blunt Chest Trauma of the 4th ventricle and/or ataxia Ataxia Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharynx, larynx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or peripheral nerve diseases. Motor ataxia may be associated with cerebellar diseases; cerebral cortex diseases; thalamic diseases; basal ganglia diseases; injury to the red nucleus; and other conditions. Ataxia-telangiectasia
    • Pleomorphic Pleomorphic Bacteroides xanthoastrocytoma:
      • Originates in temporal lobe Temporal lobe Lower lateral part of the cerebral hemisphere responsible for auditory, olfactory, and semantic processing. It is located inferior to the lateral fissure and anterior to the occipital lobe. Cerebral Cortex: Anatomy
      • Commonly associated with seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures
    • Subependymal giant cell astrocytoma (SEGA):
      • Periventricular tumors → may obstruct CSF outflow → hydrocephalus Hydrocephalus Excessive accumulation of cerebrospinal fluid within the cranium which may be associated with dilation of cerebral ventricles, intracranial. Subarachnoid Hemorrhage
      • Associated with tuberous sclerosis Tuberous sclerosis Tuberous sclerosis or tuberous sclerosis complex (TSC) is an autosomal dominant disorder with mainly neurocutaneous symptoms. Mutation in the TSC genes causes excessive tumor-like growths in the brain, eyes, heart, kidney, and lungs. Cutaneous manifestations include hypopigmentation (i.e., ash leaf spots, confetti lesions) or excessive growth (i.e., angiofibroma, shagreen patch). Tuberous Sclerosis
  • Grade II: low-grade diffuse astrocytomas
    • Also known as fibrillary astrocytomas
    • Invasive tumors with no clear separation from surrounding brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification
    • Show nuclear atypia Atypia Fibrocystic Change alone
    • May progress to glioblastoma
  • Grade III: anaplastic astrocytomas
    • Show nuclear atypia Atypia Fibrocystic Change and ↑ mitotic activity and cellularity
    • Lack necrosis Necrosis The death of cells in an organ or tissue due to disease, injury or failure of the blood supply. Ischemic Cell Damage and microvascular proliferation
    • Progression to glioblastoma, typically within 2 years
  • Grade IV: glioblastoma multiforme Glioblastoma multiforme Glioblastoma multiforme is a high-grade astrocytoma, an aggressive brain tumor arising from astrocytes, with an unknown cause and a poorly understood link to risk factors. There are two main types: primary, a more aggressive form seen more commonly in older patients, and secondary, developing from lower-grade astrocytomas and seen more commonly in younger patients. Glioblastoma Multiforme (GBM)
    • Most malignant and aggressive type of astrocytoma
    • Characterized by areas of necrosis Necrosis The death of cells in an organ or tissue due to disease, injury or failure of the blood supply. Ischemic Cell Damage or microvascular proliferation
    • May progress from a lower-grade astrocytoma (10%) or originate directly as a GBM (90%)
    • Dismal prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas

Epidemiology

  • Incidence Incidence The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time. Measures of Disease Frequency:
    • Age-standardized incidence Incidence The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time. Measures of Disease Frequency: 4.7 per 100,000 person-years
    • In the United States, 15,000 new astrocytomas are diagnosed per year.
  • Race/ethnicity: no significant differences
  • Sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria predominance:
    • No sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria predominance in pilocytic astrocytoma.
    • Slight male predominance in low-grade diffuse astrocytoma
    • Male:female predominance of approximately 2:1 in anaplastic astrocytoma
  • Grade IV astrocytomas:
    • Most common malignant primary brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tumor Tumor Inflammation: accounts for 23% of all primary brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tumors
    • 60% of all astrocytomas are grade IV at diagnosis.
Table: Epidemiologic characteristics of astrocytomas by grade
Grade Typical age of diagnosis (average age) Typical length of survival
Grade I Children and adolescents > 10 years
Grade II 20–60 years (average, 35) > 5 years
Grade III 30–60 years (average, 40) 2–5 years
Grade IV 50–80 years (average, 60) Approximately 1 year

Etiology

The cause of most astrocytomas is unknown. Ultimately, genetic mutations Genetic Mutations Carcinogenesis lead to uncontrolled cell growth and tumor Tumor Inflammation proliferation.

  • Astrocytomas occur more frequently in the following genetic disorders:
    • Li–Fraumeni syndrome (p53 germline mutations)
    • Turcot syndrome Turcot syndrome Familial Adenomatous Polyposis (mutations in several tumor Tumor Inflammation suppressor genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure, including APC APC A polyposis syndrome due to an autosomal dominant mutation of the apc genes on chromosome 5. The syndrome is characterized by the development of hundreds of adenomatous polyps in the colon and rectum of affected individuals by early adulthood. Familial Adenomatous Polyposis and MMR MMR A DNA repair pathway involved in correction of errors introduced during DNA replication when an incorrect base, which cannot form hydrogen bonds with the corresponding base in the parent strand, is incorporated into the daughter strand. Excinucleases recognize the base pair mismatch and cause a segment of polynucleotide chain to be excised from the daughter strand, thereby removing the mismatched base. Lynch syndrome)
    • Neurofibromatosis type 1 Neurofibromatosis type 1 Neurofibromatosis type 1 (NF1), also known as phakomatosis, is a neurocutaneous disorder that is most commonly of autosomal dominant inheritance due to mutations in the NF1 gene. Neurofibromatosis type 1 presents a range of clinical manifestations with the most prominent features being various pigmented skin lesions called café au lait macules (CALMs), neurofibromas, freckling of the inguinal and axillary regions, and iris hamartomas. Neurofibromatosis Type 1 ( NF1 NF1 Neurofibromatosis type 1 (NF1), also known as phakomatosis, is a neurocutaneous disorder that is most commonly of autosomal dominant inheritance due to mutations in the NF1 gene. Neurofibromatosis type 1 presents a range of clinical manifestations with the most prominent features being various pigmented skin lesions called café au lait macules (CALMs), neurofibromas, freckling of the inguinal and axillary regions, and iris hamartomas. Neurofibromatosis Type 1)
    • Tuberous sclerosis Tuberous sclerosis Tuberous sclerosis or tuberous sclerosis complex (TSC) is an autosomal dominant disorder with mainly neurocutaneous symptoms. Mutation in the TSC genes causes excessive tumor-like growths in the brain, eyes, heart, kidney, and lungs. Cutaneous manifestations include hypopigmentation (i.e., ash leaf spots, confetti lesions) or excessive growth (i.e., angiofibroma, shagreen patch). Tuberous Sclerosis
  • Ionizing radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma is an established risk factor:
    • Pituitary Pituitary A small, unpaired gland situated in the sella turcica. It is connected to the hypothalamus by a short stalk which is called the infundibulum. Hormones: Overview and Types adenoma radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma therapy: 16× increased risk of astrocytoma
    • Children who receive radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma for acute lymphocytic leukemia (ALL): 22× increased risk of developing a CNS malignancy Malignancy Hemothorax in 5–10 years (including grade II, III, and IV astrocytomas)

Pathophysiology

Pathogenesis

Several genetic mutations Genetic Mutations Carcinogenesis are associated with astrocytomas.

  • Mutations in isocitrate dehydrogenase Isocitrate dehydrogenase An enzyme of the oxidoreductase class that catalyzes the conversion of isocitrate and NAD+ to yield 2-ketoglutarate, carbon dioxide, and nadh. It occurs in cell mitochondria. The enzyme requires mg2+, mn2+; it is activated by adp, citrate, and Ca2+, and inhibited by nadh, NADPH, and ATP. The reaction is the key rate-limiting step of the citric acid (tricarboxylic) cycle. Citric Acid Cycle 1 (IDH1 gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics):
    • IDH1:
      • Catalyzes the reversible oxidative decarboxylation Decarboxylation The removal of a carboxyl group, usually in the form of carbon dioxide, from a chemical compound. Catabolism of Amino Acids of isocitrate → α-ketoglutarate (α-KG) in the tricarboxylic acid (TCA) cycle Cycle The type of signal that ends the inspiratory phase delivered by the ventilator Invasive Mechanical Ventilation 
      • Primary producer of nicotinamide adenine Adenine A purine base and a fundamental unit of adenine nucleotides. Nucleic Acids dinucleotide phosphate Phosphate Inorganic salts of phosphoric acid. Electrolytes ( NADPH NADPH Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5′-phosphate (nmn) coupled by pyrophosphate linkage to the 5′-phosphate adenosine 2. Pentose Phosphate Pathway) in most tissues, especially the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification
      • Also involved in mitigating oxidative damage
    • Mutations lead to production and buildup of a 2-hydroxyglutarate (2-HG):
      • 2-HG inhibits enzymatic function of α-ketoglutarate (KG)-dependent dioxygenases, which are involved in DNA DNA A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine). DNA Types and Structure demethylation.
      • ↑ 2-HG causes epigenetic dysregulation → can lead to tumor Tumor Inflammation development
  • Methylation Methylation Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. . Glucocorticoids (i.e., silencing) of the methylguanine methyltransferase (MGMT) promoter:
    • MGMT is an enzyme involved in DNA DNA A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine). DNA Types and Structure repair (including DNA DNA A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine). DNA Types and Structure repair after chemotherapy Chemotherapy Osteosarcoma with an alkylating agent Alkylating Agent Alkylating agents are cell cycle-independent antineoplastic drugs that work primarily by binding alkyl groups to various parts of DNA. The overall action produces cross-linking of DNA, leading to inhibition of DNA replication and DNA damage. Alkylating Agents and Platinum).
    • MGMT methylation Methylation Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. . Glucocorticoids at the promoter region:
      • Silences expression of the gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics
      • May occur during tumor Tumor Inflammation development → prevents repair of DNA damage DNA Damage Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a mutation or a block of DNA replication. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (pyrimidine dimers) or interstrand crosslinking. Damage can often be repaired (DNA repair). If the damage is extensive, it can induce apoptosis. DNA Repair Mechanisms
      • Improves chemotherapy Chemotherapy Osteosarcoma responsiveness and overall survival (independent of other risk factors) 
  • Inactivating p53 mutations (present in ⅔ of low-grade astrocytomas)
  • Overexpression of platelet-derived growth factor Platelet-derived growth factor Mitogenic peptide growth hormone carried in the alpha-granules of platelets. It is released when platelets adhere to traumatized tissues. Connective tissue cells near the traumatized region respond by initiating the process of replication. Hypertrophic and Keloid Scars alpha (PDGF-A) 
  • Certain human leukocyte antigen Antigen Substances that are recognized by the immune system and induce an immune reaction. Vaccination (HLA) types are associated with either decreased or increased risk.

Pathophysiology

  • Astrocytomas usually arise in the cerebral hemispheres (i.e., parenchyma).
  • Regional effects on brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification parenchyma include:
  • Intracranial pressure Intracranial Pressure Idiopathic Intracranial Hypertension ( ICP ICP Normal intracranial pressure (ICP) is defined as < 15 mm Hg, whereas pathologically increased ICP is any pressure ≥ 20 mm Hg. Increased ICP may result from several etiologies, including trauma, intracranial hemorrhage, mass lesions, cerebral edema, increased CSF production, and decreased CSF absorption. Increased Intracranial Pressure (ICP)) may be due to:
    • Direct mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast effect
    • Edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema in surrounding brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tissue
    • ↑ Blood volume
    • ↑ CSF volume/ hydrocephalus Hydrocephalus Excessive accumulation of cerebrospinal fluid within the cranium which may be associated with dilation of cerebral ventricles, intracranial. Subarachnoid Hemorrhage
  • Disruption of normal parenchymal functions are due to:
    • Hypoxia Hypoxia Sub-optimal oxygen levels in the ambient air of living organisms. Ischemic Cell Damage
    • Competition for nutrients
    • Release Release Release of a virus from the host cell following virus assembly and maturation. Egress can occur by host cell lysis, exocytosis, or budding through the plasma membrane. Virology of metabolic end products:
      • Free radicals Free radicals Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated. Ischemic Cell Damage
      • Altered electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes
      • Neurotransmitters
    • Release Release Release of a virus from the host cell following virus assembly and maturation. Egress can occur by host cell lysis, exocytosis, or budding through the plasma membrane. Virology and recruitment Recruitment Skeletal Muscle Contraction of cellular mediators (e.g., cytokines Cytokines Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner. Adaptive Immune Response)

Clinical Presentation

Neurologic signs and symptoms related to astrocytomas result from perturbations in CNS function.

Onset of symptoms

  • Grades I and II: Onset is usually subtle and tumors develop slowly because of the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification’s ability to temporarily adapt to the presence of a slow-growing tumor Tumor Inflammation.
  • Grades III and IV: Onset is more often sudden and/or debilitating.

Symptoms

Symptoms are primarily dependent on the location of the tumor Tumor Inflammation in the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification The symptoms are divided into 2 categories:

  • General symptoms: symptoms that can occur with tumors in any location
    • Headache Headache The symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders. Brain Abscess (usually in the morning)
    • Nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics and/or vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia 
    • Cognitive difficulties: 
      • Memory Memory Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory. Psychiatric Assessment problems
      • Mood or personality changes
    • Gait Gait Manner or style of walking. Neurological Examination disorders 
    • Ataxia Ataxia Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharynx, larynx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or peripheral nerve diseases. Motor ataxia may be associated with cerebellar diseases; cerebral cortex diseases; thalamic diseases; basal ganglia diseases; injury to the red nucleus; and other conditions. Ataxia-telangiectasia
    • Papilledema Papilledema Swelling of the optic disk, usually in association with increased intracranial pressure, characterized by hyperemia, blurring of the disk margins, microhemorrhages, blind spot enlargement, and engorgement of retinal veins. Chronic papilledema may cause optic atrophy and visual loss. Idiopathic Intracranial Hypertension
  • Focal symptoms: symptoms that occur because of tumors in specific locations
    • Seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures
      • Most common symptom of astrocytomas 
      • Low-grade tumors are more likely to cause seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures than high-grade tumors.
    • Aphasia Aphasia A cognitive disorder marked by an impaired ability to comprehend or express language in its written or spoken form. This condition is caused by diseases which affect the language areas of the dominant hemisphere. Clinical features are used to classify the various subtypes of this condition. General categories include receptive, expressive, and mixed forms of aphasia. Ischemic Stroke 
    • Visual field Visual Field The Visual Pathway and Related Disorders deficits
    • Motor Motor Neurons which send impulses peripherally to activate muscles or secretory cells. Nervous System: Histology weakness 
    • Hemiparesis Hemiparesis The term hemiparesis refers to mild to moderate weakness involving one side of the body. Epidural Hemorrhage
    • Sensory Sensory Neurons which conduct nerve impulses to the central nervous system. Nervous System: Histology abnormalities

Diagnosis

Neuroimaging Neuroimaging Non-invasive methods of visualizing the central nervous system, especially the brain, by various imaging modalities. Febrile Infant is the only test necessary to diagnose an astrocytoma. The gold standard is MRI, though CT is also sometimes used.

MRI

  • Gold standard imaging study
  • Preferably ordered with and without gadolinium Gadolinium An element of the rare earth family of metals. It has the atomic symbol gd, atomic number 64, and atomic weight 157. 25. Its oxide is used in the control rods of some nuclear reactors. Magnetic Resonance Imaging (MRI) enhancement
  • Higher-grade astrocytomas show:
  • Low-grade astrocytomas typically do not enhance with contrast.
Contrast mri showing glioblastoma multiforme

Contrast MRI showing glioblastoma multiforme Glioblastoma multiforme Glioblastoma multiforme is a high-grade astrocytoma, an aggressive brain tumor arising from astrocytes, with an unknown cause and a poorly understood link to risk factors. There are two main types: primary, a more aggressive form seen more commonly in older patients, and secondary, developing from lower-grade astrocytomas and seen more commonly in younger patients. Glioblastoma Multiforme

Image: “ Glioblastoma multiforme Glioblastoma multiforme Glioblastoma multiforme is a high-grade astrocytoma, an aggressive brain tumor arising from astrocytes, with an unknown cause and a poorly understood link to risk factors. There are two main types: primary, a more aggressive form seen more commonly in older patients, and secondary, developing from lower-grade astrocytomas and seen more commonly in younger patients. Glioblastoma Multiforme” by Duncan JS, de Tisi J. License: CC BY 3.0

CT scan

  • Indications:
    • Contraindication to MRI 
    • Acute settings (e.g., where hemorrhage and/or stroke needs to be ruled out)
    • CT of the chest/abdomen/ pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy may be warranted to look for alternative primary lesions if metastasis Metastasis The transfer of a neoplasm from one organ or part of the body to another remote from the primary site. Grading, Staging, and Metastasis is suspected.
  • Findings show a poorly defined parenchymal mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast.
  • Low-grade lesions typically do not enhance with contrast.

Other tests

Biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma

A biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma is indicated for grading Grading Methods which attempt to express in replicable terms the level of cell differentiation in neoplasms as increasing anaplasia correlates with the aggressiveness of the neoplasm. Grading, Staging, and Metastasis, and/or confirming the diagnosis after the tumor Tumor Inflammation is identified on neuroimaging Neuroimaging Non-invasive methods of visualizing the central nervous system, especially the brain, by various imaging modalities. Febrile Infant.

  • Pilocytic astrocytoma:  Rosenthal fibers Rosenthal Fibers Hemangioblastoma: eosinophilic cytoplasmic inclusions, appearing as corkscrew-like fibers
  • Low-grade diffuse astrocytoma:
    • Mild to moderate increase in number of glial cell nuclei
    • Nuclear pleomorphism
    • Nucleus Nucleus Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (cell nucleolus). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the endoplasmic reticulum. A cell may contain more than one nucleus. The Cell: Organelles:cytoplasm ratio quite high
    • Intervening feltwork of fine, glial fibrillary acidic protein (GFAP) astrocytic cell processes 
    • Grossly: poorly defined tumors that are gray in color
  • Anaplastic astrocytoma: 
    • Increased cellularity and nuclear pleomorphism
    • Marked mitotic activity and nuclear atypia Atypia Fibrocystic Change
    • High proliferative rate based on Ki67 staining
  • Glioblastoma multiforme Glioblastoma multiforme Glioblastoma multiforme is a high-grade astrocytoma, an aggressive brain tumor arising from astrocytes, with an unknown cause and a poorly understood link to risk factors. There are two main types: primary, a more aggressive form seen more commonly in older patients, and secondary, developing from lower-grade astrocytomas and seen more commonly in younger patients. Glioblastoma Multiforme:
    • Increased mitotic figures, cellularity, and nuclear pleomorphism
    • Vascular and/or endothelial cell proliferation
    • Areas of necrosis Necrosis The death of cells in an organ or tissue due to disease, injury or failure of the blood supply. Ischemic Cell Damage (grossly appear firm and white or soft and yellow)
    • Tumor Tumor Inflammation cells are “pseudopalisading.”

Management and Prognosis

Management by grade

Management depends on the grade, location of the tumor Tumor Inflammation (i.e., how much can be safely resected), and symptoms. Management typically involves a combination of surgery, radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma, and chemotherapy Chemotherapy Osteosarcoma.

  • Grade I astrocytoma:
    • Best management is controversial due to:
      • Lack of strong data
      • Relatively indolent nature of tumor Tumor Inflammation
      • Morbidity Morbidity The proportion of patients with a particular disease during a given year per given unit of population. Measures of Health Status associated with the treatments
      • Relatively young age of the typical patient
    • Consider maximal safe surgical resection if tumor Tumor Inflammation is accessible.
    • Partial surgical removal when the tumor Tumor Inflammation involves crucial parts of the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification
    • Consider radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma therapy when the tumor Tumor Inflammation is not fully resectable.
  • Grade II astrocytoma:
    • Surgical resection is recommended for accessible tumors:
      • Not curative
      • Additional therapies (i.e., radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma therapy and chemotherapy Chemotherapy Osteosarcoma) are ultimately required in all patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship.
    • Radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma plus adjuvant Adjuvant Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (freund’s adjuvant, bcg, corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity. Vaccination chemotherapy Chemotherapy Osteosarcoma (typically temozolomide Temozolomide A dacarbazine derivative that is used as an alkylating antineoplastic agent for the treatment of malignant glioma and malignant melanoma. Alkylating Agents and Platinum
    • Follow-up to check for recurrence/progression
  • Grade III and IV astrocytomas:
    • Standard therapy is surgery, radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma, and chemotherapy Chemotherapy Osteosarcoma (typically with temozolomide Temozolomide A dacarbazine derivative that is used as an alkylating antineoplastic agent for the treatment of malignant glioma and malignant melanoma. Alkylating Agents and Platinum).
    • Surgery may include:
      • Resection 
      • Symptom-relieving procedures (e.g., shunt placement to relieve hydrocephalus Hydrocephalus Excessive accumulation of cerebrospinal fluid within the cranium which may be associated with dilation of cerebral ventricles, intracranial. Subarachnoid Hemorrhage)
    • If surgery is not possible, then radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma and chemotherapy Chemotherapy Osteosarcoma are used.
  • Other therapy to consider:
    • DVT DVT Deep vein thrombosis (DVT) usually occurs in the deep veins of the lower extremities. The affected veins include the femoral, popliteal, iliofemoral, and pelvic veins. Proximal DVT is more likely to cause a pulmonary embolism (PE) and is generally considered more serious. Deep Vein Thrombosis prophylaxis Prophylaxis Cephalosporins in nonambulatory and hospitalized patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship
    • Anticonvulsant Anticonvulsant Anticonvulsant drugs are pharmacological agents used to achieve seizure control and/or prevent seizure episodes. Anticonvulsants encompass various drugs with different mechanisms of action including ion-channel (Na+ and Ca+2) blocking and GABA reuptake inhibition. First-Generation Anticonvulsant Drugs therapy in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with a history of seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures (prophylactic anticonvulsant Anticonvulsant Anticonvulsant drugs are pharmacological agents used to achieve seizure control and/or prevent seizure episodes. Anticonvulsants encompass various drugs with different mechanisms of action including ion-channel (Na+ and Ca+2) blocking and GABA reuptake inhibition. First-Generation Anticonvulsant Drugs therapy remains controversial)
    • Corticosteroids Corticosteroids Chorioretinitis (e.g., dexamethasone Dexamethasone An anti-inflammatory 9-fluoro-glucocorticoid. Antiemetics) may be used for their antiinflammatory properties to reduce tumor Tumor Inflammation mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast effect.

Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas

Factors that affect Affect The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves. Psychiatric Assessment prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas include:

  • Tumor Tumor Inflammation grade:
    • Grade I: 96% 5-year survival rate
    • Grade II: Median survival is 8 years.
    • Grade III: Median survival is 2–5 years.
    • Grade IV: Median survival is 15 months.
  • Extent of surgical resection
  • Use of adjuvant Adjuvant Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (freund’s adjuvant, bcg, corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity. Vaccination radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma therapy and/or chemotherapy Chemotherapy Osteosarcoma
    • Age: younger age at diagnosis associated with longer survival.
  • Functional status (e.g., minimal symptoms and/or normal neurologic function) associated with longer survival

Related videos

Differential Diagnosis

When a patient presents with neurologic symptoms on exam, the differential diagnosis may include vascular processes (e.g., hemorrhage, infarct Infarct Area of necrotic cells in an organ, arising mainly from hypoxia and ischemia Ischemic Cell Damage), infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease (e.g., abscess Abscess Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection. Chronic Granulomatous Disease, viral encephalitis Encephalitis Encephalitis is inflammation of the brain parenchyma caused by an infection, usually viral. Encephalitis may present with mild symptoms such as headache, fever, fatigue, and muscle and joint pain or with severe symptoms such as seizures, altered consciousness, and paralysis. Encephalitis), and inflammatory processes (e.g., multiple sclerosis Multiple Sclerosis Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease that leads to demyelination of the nerves in the CNS. Young women are more predominantly affected by this most common demyelinating condition. Multiple Sclerosis) in addition to primary brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tumors. Imaging is typically able to narrow the differential to a brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tumor Tumor Inflammation.

  • Oligodendroglioma Oligodendroglioma Oligodendrogliomas are malignant CNS tumors arising from neural glial cell precursors. Oligodendrogliomas often arise in the frontal lobes of the brain and have a generally favorable prognosis when compared to other gliomas. Oligodendrogliomas are the 3rd most common CNS tumor. The most frequent presenting symptom is a seizure. Oligodendroglioma: CNS tumor Tumor Inflammation arising from oligodendrocytes. Oligodendroglioma Oligodendroglioma Oligodendrogliomas are malignant CNS tumors arising from neural glial cell precursors. Oligodendrogliomas often arise in the frontal lobes of the brain and have a generally favorable prognosis when compared to other gliomas. Oligodendrogliomas are the 3rd most common CNS tumor. The most frequent presenting symptom is a seizure. Oligodendroglioma most commonly develops in the cerebral hemisphere, usually in the frontal lobe Frontal lobe The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus. Cerebral Cortex: Anatomy. Oligodendrogliomas can present with focal neurologic deficits Neurologic Deficits High-Risk Headaches, seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures, and personality changes depending on its exact location. Diagnosis is made by MRI and biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma. Management involves surgical resection, possibly accompanied by radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma and/or chemotherapy Chemotherapy Osteosarcoma.
  • Medulloblastoma Medulloblastoma Medulloblastomas are malignant primitive neuroectodermal tumors that arise in the posterior fossa in children. Medulloblastomas are the most common malignant brain tumors in children. Patients with medulloblastoma present with symptoms of increased intracranial pressure and cerebellar signs, which both evolve and worsen over weeks to a few months. Medulloblastoma: tumor Tumor Inflammation that arises in the posterior fossa. Medulloblastoma Medulloblastoma Medulloblastomas are malignant primitive neuroectodermal tumors that arise in the posterior fossa in children. Medulloblastomas are the most common malignant brain tumors in children. Patients with medulloblastoma present with symptoms of increased intracranial pressure and cerebellar signs, which both evolve and worsen over weeks to a few months. Medulloblastoma is the most common malignant brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tumor Tumor Inflammation in children. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with symptoms of increased ICP ICP Normal intracranial pressure (ICP) is defined as < 15 mm Hg, whereas pathologically increased ICP is any pressure ≥ 20 mm Hg. Increased ICP may result from several etiologies, including trauma, intracranial hemorrhage, mass lesions, cerebral edema, increased CSF production, and decreased CSF absorption. Increased Intracranial Pressure (ICP) as well as cerebellar signs that generally worsen over time. Diagnosis is suspected based on MRI findings, but histopathologic analysis at the time of surgical resection is required for diagnosis. Treatment is with a combination of surgery, radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma therapy, and chemotherapy Chemotherapy Osteosarcoma
  • Ependymoma Ependymoma Ependymomas are glial cell tumors arising from CSF-producing ependymal cells lining the ventricular system. Ependymomas most commonly occur within the posterior fossa in contact with the 4th ventricle, or within the intramedullary spinal cord. Ependymoma: subset of glial tumors that often arise in or adjacent to the ependymal lining of the ventricular system Ventricular System The ventricular system is an extension of the subarachnoid space into the brain consisting of a series of interconnecting spaces and channels. Four chambers are filled with cerebrospinal fluid (CSF): the paired lateral ventricles, the unpaired 3rd ventricle, and the unpaired 4th ventricle. Ventricular System: Anatomy, most commonly within the posterior fossa, in contact with the 4th ventricle, or within the intramedullary spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy. The clinical presentation varies depending on the location of the tumor Tumor Inflammation. MRI is the standard imaging technique, but histologic confirmation is required for diagnosis. Treatment involves surgical resection and adjuvant Adjuvant Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (freund’s adjuvant, bcg, corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity. Vaccination radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma or chemotherapy Chemotherapy Osteosarcoma (based on age). 
  • Metastatic tumor Tumor Inflammation: neoplastic cells that have spread to the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification from primary tumors elsewhere in the body. Metastatic neoplasms Neoplasms New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms. Benign Bone Tumors are the most common neoplasms Neoplasms New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms. Benign Bone Tumors in the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification. Neuroimaging Neuroimaging Non-invasive methods of visualizing the central nervous system, especially the brain, by various imaging modalities. Febrile Infant often shows multiple foci of the carcinoma, suggesting nonbrain origin. Clinical presentation depends on the primary tumor Tumor Inflammation and location and extent of brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification metastasis Metastasis The transfer of a neoplasm from one organ or part of the body to another remote from the primary site. Grading, Staging, and Metastasis. Treatment is directed at the underlying neoplasm and may involve surgical resection, radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma therapy, and chemotherapy Chemotherapy Osteosarcoma.

References

  1. DeAngelis, L. M., Wen, P. Y. (2018). Primary and metastatic tumors of the nervous system. In Jameson J., et al. (Eds.), Harrison’s Principles of Internal Medicine, 20th ed. McGraw-Hill. https://accessmedicine-mhmedical-com.aucmed.idm.oclc.org/content.aspx?bookid=2129&sectionid=192016511
  2. Kapoor, M., Gupta, V. (2021). Astrocytoma. StatPearls. Retrieved May 2, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK559042/
  3. Recht, L., van den Bent, M., Shih, H. (2021). Treatment and prognosis of diffuse (grade II) and anaplastic (grade III) astrocytomas in adults. In Wen, P., Loeffler, J. (Ed.), UpToDate. Retrieved May 2, 2021, from https://www.uptodate.com/contents/treatment-and-prognosis-of-diffuse-grade-ii-and-anaplastic-grade-iii-astrocytomas-in-adults
  4. Kennedy, B. (2020). Astrocytoma. In Engelhard, H. (Ed.), Medscape. Retrieved May 2, 2021, from https://reference.medscape.com/article/283453-overview 
  5. Kumar, V., Abbas, A. K., Aster, J. C. (2015). Robbins & Cotran Pathologic Basis of Disease. Philadelphia: Elsevier Saunders.
  6. National Cancer Institute. (2020). Childhood astrocytomas treatment (PDQ®)—patient version. Retrieved April 29, 2021, from https://www.cancer.gov/types/brain/patient/child-astrocytoma-treament-pdq
  7. National Organization of Rare Diseases. (2017). Anaplastic astrocytoma. Retrieved April 29, 2021, from https://rarediseases.org/rare-diseases/anaplastic-astrocytoma/
  8. National Organization of Rare Diseases. (2015). Astrocytoma. Retrieved April 29, 2021, from https://rarediseases.org/rare-diseases/astrocytoma/ 
  9. Peruzzi, P., Prabhu, V. (n.d.). Astrocytoma tumors. American Association of Neurological Surgeons. Retrieved April 29, 2021, from https://www.aans.org/en/Patients/Neurosurgical-Conditions-and-Treatments/Astrocytoma-Tumors

USMLE™ is a joint program of the Federation of State Medical Boards (FSMB®) and National Board of Medical Examiners (NBME®). MCAT is a registered trademark of the Association of American Medical Colleges (AAMC). NCLEX®, NCLEX-RN®, and NCLEX-PN® are registered trademarks of the National Council of State Boards of Nursing, Inc (NCSBN®). None of the trademark holders are endorsed by nor affiliated with Lecturio.

Create your free account or log in to continue reading!

Sign up now and get free access to Lecturio with concept pages, medical videos, and questions for your medical education.

User Reviews

¡Hola!

Esta página está disponible en Español.

Details