Intracranial neoplasms Flashcards
intracranial neoplasms
-Primary tumors= originated in CNS
-Secondary tumors = Metastasized to CNS
-Incident of new brain tumor = 6.4 per 100,000 persons
-Overall 5-year survival rate = 33.4%
-Peak age 55-64 years old
-Types of brain tumors:
-Glial tumors (30% of primary tumors), Meningiomas (35%), Schwannomas (10%), CNS lymphomas (2%)
grading (according to WHO)
-histology and invasive
-Grade 1 = Least malignant (benign)
-Grade 2 = Relatively slow growing but can recur as a higher grade
-Grade 3 = Malignant, infiltrative, 2-3 year survival rate
-Grade 4 = Most malignant and life threatening
tumors of meninges
-Meningiomas (MC primary brain tumor)!!!
-Mesenchymal tumors
-Primary melanocytic lesions
-Other meningeal neoplasms
-mostly benign
tumors of neuroepithelial tissue
-from the brain tissue
-Gliomas 2nd MC category after meningiomas
-Astrocytomas (fastest growing brain cancer) -> Glioblastoma multiforme!!!!!!
-Oligodendrogliomas (dont memorize)
-Ependymomas (child) (dont memorize)
-Medulloblastomas (most common malignant brain tumor in children )
other types of tumors
-Retinoblastomas!!!
-Pituitary tumors and craniopharyngiomas
-Nerve sheath tumors (shwannomas)
-Lymphomas (usually metastatic)
-Germ cell tumors (teratomas)
-Hemangiomas
-dont need to know
intracranial neoplasms: validated risk factors
-Ionizing radiation (meningiomas, gliomas, schwannomas)!!!! -> brain CT
-Immunosuppression (CNS lymphoma)!!!!
-genetics:
-!Neurofibromatosis -> Café au lait spot
-Von Hippel-Lindau disease
-Tuberous scclerosis
-Turcot syndrome
-Cowden disease
-Gorlin syndrome
unproven risk factors for intracranial neoplasms (dont need to know)
-Alcohol use
-Cellular telephones
-Chemical agents (e.g., hair dyes, solvents, pesticides, traffic-related air pollution)
-Extremely low-frequency electromagnetic fields
-Head trauma or injury
-Infections (e.g., viruses,Toxoplasma gondii, in utero influenza, varicella)
-Nitrosamine, nitrosamide, nitrite, nitrate, or aspartame consumption
-Occupational exposures (e.g., rubber, vinyl chloride, petroleum)
-Tobacco use
general sx of brain tumors
-usually asymptomatic
-Headaches- Initial symptom in 23-30%
-Seizure activity
-Initial symptom in 21-33% of cases
-Present in 50-70% of cases at some stage
-New onset seizure as an adult? 10-20% have a brain tumor
-AMS
-Initial symptom in 15-20% of cases
-May have slight or severe changes to concentration, memory, affect, personality, initiative, abstract reasoning, cognitive problems, confusion
-Papilledema- for fast growing ones
“classic headache associated with tumor!
-HA interrupts sleep
-!HA worse in the morning, improves throughout day
-Associated with nausea / vomiting! - especially intermittent
-HA is postural!, or worsened with cough / exercise / exertion!
-HA is different or more severe than usual
-!New HA in person 50+ w/o hx of HA
-Findings of papilledema, focal neuro signs!
focal symptoms of brain tumors
-Symptoms largely depend on size, type, location!!
-Generally, these are the most common findings by lobe:
-Frontal lobe = personality changes, dementia
-Parietal lobe = receptive aphasia, sensory loss, spatial disorientation
-Temporal lobe = Seizures
-Occipital lobe = Vision changes including contralateral hemianopia
-Thalamus = Hemisensory loss, behavioral changes, language disorders
-Cerebellum = Ataxia, dysmetria, nystagmus
-Brain stem = Cranial nerve changes, ataxia, pupil changes, nystagmus, hemiparesis, autonomic dysfunction
radiographic dx
-1st choice:
-CT scan
-Static image
-Ionizing radiation
-Contrast enhancement improves sensitivity
-Often first line d/t lower cost, shorter time, accessibility, and sensitivity to detect bony involvement
-Preferred:
-!MRI w/ and w/o contrast = imaging procedure of choice
-Static image
-Contrast enhancement sharpens the definition of lesions, and can distinguish edema vs. tumor
-Cannot predict tumor type of malignancy grade (needs biopsy)
DONT know the below:
-PET scan (Positron emission tomography)
-Dynamic imaging
-Uses radioactive markers to measure glucose metabolism which is useful in determining the grade of tumor
-Expensive and less reliable after heavy chemo therapy
-SPECT (Single photon emission CT)
-Functional imaging
-Assess cerebral blood flow to determine tumor location
-fMRI (Functional MRI)
-MRI+Echo planar technology to map cerebral blood flow
-Computed integration imaging
-3 dimensional recontructions of the cranial space by combingin images from all the above
-Provides safer more accurate method of biosy, laser guided resection
diagnosis of tumor
-BIOPSY is definitive
-Stereotactic biopsy = computer direct needle biopsy
-EEG = often normal in brain tumors
-LP = CSF analysis -> maybe its an abcess
-dont help with dx but help:
-Endocrine testing = hypothalamic and pituitary tumors
-Audiometry and vestibular testing = tumors near cerebellopontine angle
-Perimetry = measuring visual fields in tumors near optic chiasm
tumor tx
-surgery:
-craniotomy- not close to anything else, not deep
-awake brain tumor surgery- if its close to important structures
-neuroendoscopy- through the nose if its frontal
-radiation:
-external beam radiation
-stereotactic radiosurgery
-chemotherapy
-targeted drug therapy
meningiomas
-MC primary “brain tumor”!!!
-Most are benign !
-Risk factor: Radiation
-May be associated with neurofibromatosis type 2!, schwannomatosis!, MEN 1!
-Often asymptomatic! due to slow growing nature
-Can cause seizures (30%), obstruction hydrocephalus (if encroaches on posterior fossa)
meningiomas: dx and tx
-MRI/CT scan with and without contrast
-Extra-axial! and dural-based mass! with homogenous signal changes and smooth contours
-Diagnosis: requires biopsy to differentiate from other tumors
-Management:
-Observation with serial MRI if asymptomatic
-leave it alone until…..
-Surgical removal if symptomatic
-Prognosis: Good, rarely recur once removed
-once gone its gone
