Brain tumor classification: Difference between revisions

	Brain tumor Microchapters
Patient Information
Overview
Classification Adult brain tumors Glioblastoma multiforme Oligodendroglioma Meningioma Hemangioblastoma Pituitary adenoma Schwannoma Primary CNS lymphoma Childhood brain tumors Pilocytic astrocytoma Medulloblastoma Ependymoma Craniopharyngioma Pinealoma Metastasis Lung cancer Breast cancer Melanoma Gastrointestinal tract cancer Renal cell carcinoma Osteoblastoma Head and neck cancer Neuroblastoma Lymphoma Prostate cancer
Causes
Differentiating Brain Tumor from other Diseases

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Latest revision as of 02:33, 6 November 2017

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Sujit Routray, M.D. [2]

Overview

Brain tumors can be classified into two main categories: primary and secondary tumors. Primary tumors originate in astrocytes, oligodendrocytes and ependymal cells. Secondary tumors originate in malignant cancers located primarily in other organs. Brain tumors are classified depending on location of the tumor, type of tissue involved and whether they are benign or malignant.

Classification

Primary tumors

Tumors occurring in the brain include:

Most primary brain tumors originate from glia (gliomas) such as astrocytes (astrocytomas), oligodendrocytes (oligodendrogliomas), or ependymal cells (ependymoma). There are also mixed forms, with both an astrocytic and an oligodendroglial cell component. These are called mixed gliomas or oligoastrocytomas. Plus, mixed glio-neuronal tumors (tumors displaying a neuronal, as well as a glial component, e.g. gangliogliomas, disembryoplastic neuroepithelial tumors) and tumors originating from neuronal cells (e.g. gangliocytoma, central gangliocytoma) can also be encountered.

Other origins of primary brain tumors include: primitive neuroectodermal tumors (PNET, e.g. medulloblastoma, medulloepithelioma, neuroblastoma, retinoblastoma, ependymoblastoma), tumors of the pineal parenchyma (e.g. pineocytoma, pineoblastoma), ependymal cell tumors, choroid plexus tumors, neuroepithelial tumors of uncertain origin (e.g. gliomatosis cerebri, astroblastoma), etc.

Secondary tumors and non-tumor lesions

Secondary or metastatic brain tumors originate from malignant tumors (cancers) located primarily in other organs. Their incidence is higher than that of primary brain tumors. These tumor cells reach the brain via the blood-stream. The most frequent types of metastatic brain tumors are:

Some non-tumoral masses and lesions can mimic tumors of the central nervous system. These include:

Tuberculosis of the brain
Cerebral abscess (commonly in toxoplasmosis)
Hamartomas (for example, in tuberous sclerosis)
Von Recklinghausen neurofibromatosis

References

Template:WikiDoc Sources

@@ Line 4: / Line 4: @@
 ==Overview==
-Brain tumors can be classified into two main categories: primary and secondary tumors. Primary tumors originate in astrocytes, oligodendrocytes and ependymal cells. Secondary tumors originate in malignant cancers located primarily in other organs.
+Brain tumors can be classified into two main categories: primary and secondary tumors. Primary tumors originate in astrocytes, oligodendrocytes and ependymal cells. Secondary tumors originate in malignant cancers located primarily in other organs. Brain tumors are classified depending on location of the tumor, type of tissue involved and whether they are benign or malignant.
 ==Classification==
 ===Primary tumors===
-Tumors occurring in the brain include:  [[astrocytoma]], [[pilocytic astrocytoma]], [[dysembryoplastic neuroepithelial tumor]], [[oligodendrogliomas]], [[ependymoma]], [[glioblastoma multiforme]], [[mixed gliomas]], [[oligoastrocytomas]], [[medulloblastoma]], [[retinoblastoma]], [[neuroblastoma]], [[germinoma]] and [[teratoma]].
+Tumors occurring in the brain include:
+* [[Astrocytoma]]
+* [[Pilocytic astrocytoma]]
+* [[Dysembryoplastic neuroepithelial tumor]]
+* [[Oligodendrogliomas]]
+* [[Ependymoma]]
+* [[Glioblastoma multiforme]]
+* [[Mixed gliomas]]
+* [[Oligoastrocytomas]]
+* [[Medulloblastoma]]
+* [[Retinoblastoma]]
+* [[Neuroblastoma]]
+* [[Germinoma]]
+* [[Teratoma]]
 Most primary brain tumors originate from [[glial cells|glia]] ([[glioma]]s) such as astrocytes ([[astrocytomas]]), oligodendrocytes ([[oligodendrogliomas]]), or ependymal cells ([[ependymoma]]). There are also mixed forms, with both an astrocytic and an oligodendroglial cell component. These are called [[mixed gliomas]] or [[oligoastrocytomas]]. Plus, mixed glio-neuronal tumors (tumors displaying a neuronal, as well as a glial component, e.g. [[ganglioglioma]]s, [[disembryoplastic neuroepithelial tumor]]s) and tumors originating from neuronal cells (e.g. [[gangliocytoma]], central gangliocytoma) can also be encountered.
-Other varieties of primary brain tumors include: [[primitive neuroectodermal tumor]]s (PNET, e.g. medulloblastoma]], medulloepithelioma, [[neuroblastoma]], [[retinoblastoma]], [[ependymoblastoma]]), tumors of the [[pineal gland|pineal]] [[parenchyma]] (e.g. pineocytoma, pineoblastoma), [[ependyma]]l cell tumors, [[choroid plexus]] tumors, neuroepithelial tumors of uncertain origin (e.g. [[gliomatosis cerebri]], astroblastoma), etc.
+Other origins of primary brain tumors include: [[primitive neuroectodermal tumor]]s (PNET, e.g. [[medulloblastoma]], medulloepithelioma, [[neuroblastoma]], [[retinoblastoma]], [[ependymoblastoma]]), tumors of the [[pineal gland|pineal]] [[parenchyma]] (e.g. pineocytoma, pineoblastoma), [[ependyma]]l cell tumors, [[choroid plexus]] tumors, neuroepithelial tumors of uncertain origin (e.g. [[gliomatosis cerebri]], astroblastoma), etc.
 ===Secondary tumors and non-tumor lesions===
-Secondary or [[metastasis|metastatic brain tumors]] originate from [[malignant tumors]] (cancers) located primarily in other organs. Their incidence is higher than that of primary brain tumors. The most frequent types of metastatic brain tumors originate in the [[lung]], [[skin]] ([[malignant melanoma]]), [[kidney]] ([[hypernephroma]]), [[breast]] ([[breast carcinoma]]), and [[colon (anatomy)|colon]] ([[colon carcinoma]]). These tumor cells reach the brain via the blood-stream.
-Some non-tumoral masses and lesions can mimic tumors of the [[central nervous system]]. These include [[tuberculosis]] of the brain, [[cerebral abscess]] (commonly in [[toxoplasmosis]]), and [[hamartomas]] (for example, in [[tuberous sclerosis]] and [[von Recklinghausen neurofibromatosis]]).
+Secondary or [[metastasis|metastatic brain tumors]] originate from [[malignant tumors]] (cancers) located primarily in other organs. Their incidence is higher than that of primary brain tumors. These tumor cells reach the brain via the blood-stream. The most frequent types of metastatic brain tumors are:
+*[[Lung]] cancer
+*[[Skin]] cancer
+*[[Malignant melanoma]]
+*[[Hypernephroma]]
+*[[Breast]] cancer
+*[[Colon carcinoma]]
-Symptoms of brain tumors may depend on two factors: tumor size (volume) and tumor location. The time point of symptom onset in the course of disease correlates in many cases with the nature of the tumor ("benign", i.e. slow-growing/late symptom onset, or malignant (fast growing/early symptom onset).
+Some non-tumoral masses and lesions can mimic tumors of the [[central nervous system]]. These include:
+*[[Tuberculosis]] of the brain
-Many low-grade (benign) tumors can remain [[asymptomatic]] (symptom-free) for years and they may accidentally be discovered by imaging exams for unrelated reasons (such as a minor trauma).
+*[[Cerebral abscess]] (commonly in [[toxoplasmosis]])
+*[[Hamartomas]] (for example, in [[tuberous sclerosis]])
-New onset of [[epileptic seizures|epilepsy]]<ref>Lopez MBS, Laws ER Jr. Neurosurgical Focus 12(2), Article 1, 2002. <!--PMID not yet indexed--></ref> is a frequent reason for seeking medical attention in brain tumor cases.
+*[[Von Recklinghausen neurofibromatosis]]
-Large tumors or tumors with extensive perifocal swelling [[edema]] inevitably lead to elevated [[intracranial pressure]] ([[intracranial hypertension]]), which translates clinically into [[headaches]], [[vomiting]] (sometimes without [[nausea]]), altered state of [[consciousness]] ([[somnolence]], [[coma]]), dilatation of the pupil on the side of the lesion ([[anisocoria]]), [[papilledema]] (prominent [[optic disc]] at the funduscopic examination). However, even small tumors obstructing the passage of [[cerebrospinal fluid]] (CSF) may cause early signs of increased [[intracranial pressure]]. Increased [[intracranial pressure]] may result in [[herniation]] (i.e. displacement) of certain parts of the brain, such as the [[cerebellar tonsils]] or the temporal [[uncus]],  resulting in lethal [[brainstem]] compression. In young children, elevated [[intracranial pressure]] may cause an increase in the diameter of the [[skull]] and bulging of the [[fontanelle]]s.
-Depending on the tumor location and the damage it may have caused to surrounding [[brain]] structures, either through compression or infiltration, any type of focal neurologic symptoms may occur, such as [[cognitive]] and [[behavioral]] impairment, [[Wiktionary:personality|personality]] changes, [[hemiparesis]], (hemi) [[hypesthesia]], [[aphasia]], [[ataxia]], [[visual field]] impairment, [[facial paralysis]], [[double vision]], [[tremor]] etc. These symptoms are not specific for brain tumors - they may be caused by a large variety of neurologic conditions (e.g. [[stroke]], [[traumatic brain injury]]). What counts, however, is the location of the lesion and the functional systems (e.g. motor, sensory, visual, etc.) it affects.
-A bilateral temporal [[visual field]] defect ([[bitemporal hemianopia]]&mdash;due to compression of the [[optic chiasm]]), often associated with endocrine disfunction&mdash;either [[hypopituitarism]] or hyperproduction of pituitary [[hormones]] and [[hyperprolactinemia]] is suggestive of a pituitary tumor.
-===Specific tumor types===
-Brain tumors are classified depending on:
-* Location of the tumor
-* Type of tissue involved
-* Whether they are noncancerous (benign) or cancerous (malignant)
-* Other factors
-Sometimes, tumors that start out less aggressive can change their biologic behavior and become more aggressive.
-Tumors can occur at any age, but many types are most common in a certain age group. In adults, gliomas and meningiomas are the most common.
-Gliomas come from glial cells such as astrocytes, oligodendrocytes, and ependymal cells. Gliomas are divided into three types:
-* Astrocytic tumors include astrocytomas (can be noncancerous), anaplastic astrocytomas, and glioblastomas.
-* Oligodendroglial tumors. Some primary brain tumors are made up of both astrocytic and oligodendrocytic tumors. These are called mixed gliomas.
-* Glioblastomas are the most aggressive type of primary brain tumor.
-Meningiomas and schwannomas are two other types of brain tumors. These tumors:
-* Occur most often between ages 40 and 70.
-* Are usually noncancerous, but can still cause serious complications and death from their size or location. Some are cancerous and aggressive.
-Other primary brain tumors in adults are rare. These include:
-* Ependymomas
-* Craniopharyngiomas
-* Pituitary tumors
-* Primary (central nervous system - CNS) lymphoma
-* Pineal gland tumors
-* Primary germ cell tumors of the brain<ref name="nlmnihgov">National Library of Medicine.http://www.nlm.nih.gov/medlineplus/cancer.html</ref>
 ==References==
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 [[Category:Neurology]]
 [[Category:Mature chapter]]
+ [[Category:Up-To-Date]]
+[[Category:Oncology]]
+[[Category:Medicine]]
+[[Category:Neurology]]
+[[Category:Neurosurgery]]