Tumors

Increased intracranial pressure. Brain tumors.

Dr. Ilniczky Sándor

Intracranial compartments, intracranial pressure

• Monroe-Kelly doctrine: the summarized volume of the intracranial components (brain tissue, blood, CSF) is constant. Inrease of any of them is possible only at the expense of the other two, and inceases the intracranial pressure.

• Normal CSF pressure: 100-170 mmH2O (by lumbar puncture in a lying position)

Symptoms of increased intracranial pressure

• Headache (diffuse, continuus, progressive in character)

• Nausea, vomitus (mainly in the morning)

• Disturbances of consciousness level

• Cushing phenomenon: bradycardia, bradypnoe, increased systolic blood pressure

• Bilateral edema of the optic disc

• Diplopia (due to bilateral abducent nerve palsy)

Causes of increased intracranial pressure

• Space-occupying lesions • tumors, brain oedema, inflammation, abscess,

haemorrhage (intracerebral, epidural, subdural), brain infarction, brain contusion, occlusive hydrocephalus, parasites.

• Changes in CSF subarachnoideal hemorrhage, meningitis, hindered resorbtion of CSF.

• Circulatory disturbances• extremely high arterial blood pressure, thrombosis of the

cerebral veins or venous sinuses.

Brain oedema• A common consequence of several different

pathological processes, a general reaction of brain tissue for diverse harmful effects

• Cytotoxic (intracellular). Disfunction of the

proton pump of the cell membranes, water accumulation within brain cells (anoxia, ischaemic damage, metabolic diseases)

• Vasogenic (extracellular). Breakdown of the blood-brain-barrier. Fluid extravasation.

• (hypertensive crisis, inflammations, contusion, tumors.

• Interstitial (in hydrocephalus, around ventricles)

Herniations • Shifting of brain tissue from one intracranial

compartment to another, as a consequence of mass lesions. Importance:Importance: emergency, life threatening condition.

• Types 1. 1. Trantentorial (uncus of the temporal lobe into the opening of the tentorium).

• Symptoms:

• Oculomotor nerve palsy ipsilaterally.

• Ipsilateral hemiparesis due to the compression ot the contralateral midbrain by the edge of the tentorium.

• Cortical blindness due to bilateral occipital infarction resulted from compression of both posterior cerebral arteries.

• Decreased level of consciousness, coma, respiratory problems (Cheyne-Stokes) after severe damage of the midbrain.

Herniations • 2. Cerebellar- foramen magnum herniation (the cerebellar tonsils

impacted into the foramen magnum, compressing the medulla oblongata). Causes: mass in the posterior fossa, great supratentorial mass lesion or general brain swelling.

• Symptoms:

• episodic tonic extensions-abduction ot the limbs.

• respiratory disturbances, cardiac irregularity (causes of death)

• paresis of all limbs, bilateral pyramidal signs.

• Neck stiffness, head tilt.

• Consciosusness relatively preserved, but finally coma.

Herniations

• 3. Subfalcial (lateral) herniation (the cingulum shifted under the falx cerebri to the other side) Cause: great, unilateral space-occupiing.

Herniations

Brain tumors - symptoms • Insidous development of symptoms is typical for brain tumors.

• Sudden worsening or onset ot new symptoms may be a consequence ot intratumoral haemorrhage, or herniation.

Brain tumors - symptoms • 1. Focal signs. Direct effect of the tumor itself.

• Damaged function (e. g. paresis, hypaesthesia, visual field defect, etc.)

• Positive symptoms - focal or secondarily generalized epileptic seisures, helpful in localizing the tumor.

• 2. Compression signs - on surrounding structures, tracts, cranial nerves, CSF pathways resulting in hydrocephalus.

• 3. General symptoms caused by the increased intracranial pressure, mass effect of the tumor, independent from its nature.

• 4. Psychic signs -cognitive, behavioural or personality changes (sometimes leading or only features of the tumor.)

• 5. Hormonal changes - result of disfunction of the pituitary gland.

» (hyper or hypofunction)

Brain tumors - diagnostics

• Sometimes tumor may be exactly localized by the findings of the physical examination.

• In the suspicion of brain tumor imaging methods are indicated.

• Brain CT. Administration of contrast media (containing iodine) is necessary. Some tumors are isodense and indetectable on non-contrast scans. Most tumors enhance CM, may contain central necrosis (most malignant ones). Prifocal oedema indicates a primary or metastatic malignant tumor. CT is not proper for small tumors, mainly in the posterior fossa (bony artefacts). CT is prior to MR in evaluation of intratumoral calcification an bone destruction.

• Some tumors have characteristic CT features (e.g. meningiomas)

Brain tumors - diagnostics • Brain MR. The proper method of diadnostics of brain tumors. More

detailed spatial resolution, multi-planar imaging, all parts of the brain are well visualized.

• Special tchniques (diffusion, perfusion MR, MR-angiography, MR spectroscopy, functional MRI, contrast enhanced MR)

• The best method for surgical planning.

• Angiography. Disclosing of the blood supply of some hyper-vascularized tumors (e.g. angiomas, meningiomas)

Brain tumors - diagnostics • Brain SPECT and PET. Evaluation of circulation and metabolism of

tumors.

• Differentation between tumors and lesions of other nature in in contraversary cases.

• Brain biopsy. CT assisted, „stereotaxic” procedure. Exact histological classification of tumors. Grading.

• Additional tests.

• CSF examination.

• EEG

• Evoked potentials.

• Hormonal tests.

• Genetics.

Brain tumors - classification • Neuroepithelial tumors

• Tumors of the peripheral nerves

• Tumors originated from the meninges

• Tumors of the hemopoietic system, affecting nervous system

• Germinal tumors

• Sellar tumors

• Tumors, spreading from the surounding structures to the brain

• Metastatic tumors

Neuroepithelial tumors • Astrocytomas Graded from A 1 to A 4. The most malignant form is

anaplastic astrocytoma, Glioblastoma multiforme (A3-4)

– In older patients. Localized in the hemispheres. High malignancy, rapid growth, infiltrative spreading. Butterfly tumor, transcallosal propagation.

• Symptoms: seisures, focal signs, elevated intracranial pressure, headache, psychiatric disorders (depression, behavioural, personality changes)

• Dg: CT, MR. Necrotic, irregular tumor mass, marginal enhancement, widespread perifocal oedema. Brain biopsy.

• Treatment: surgical: total removal is not possible. Irradiation and chemotheraby mav be added. High rate of recurrence, poor survival (maximum 1,5 year, average a few months)

Glioblastoma multiforme

Astrocytoma

Neuroepithelial tumors • Oligodendroglioma. Rare, hemispherial tumor. Usually calcificated.

Slow propagation, not very malignant, but sometimes transfers to malignancy, to Glioblastoma multiforme. Highly epileptogenic.

• Symptoms: seisures, focal signs.

• Dg: CT, MR. Calcificated, circumscribed mass,

• slight perifocal oedema. Brain biopsy is diagnostic.

• Treatment: surgical: total removal.

• Antiepileptic medication.

• Ependymal tumors

• Chorioid plexus tumors within ventricles, may lead to increased CSF production.

• Pineal tumors. - Parinaud syndrome.

Neuroepithelial tumors • Embryonic tumors

• Most important: Medulloblastoma. The most malignant childhood brain tumor, originated from the vermis of the cerebellum.

• Invasive, infiltrating growth, high risk of recurrence, metastatizes by CSF.

• Symptoms: headache, nausea, vomiting, dysbalance, frequent falling. Brainstem symptoms.

• Dg: CT, MR. Enhancing, space occupying mass in the posterior fossa, causing CSF circulatory block, hydrocephalus.

• Treatment: surgical + Chemotherapy. Recently long (5-7 years)

• Others: teratomas

Medulloblastoma, CT with CM

Histology

Tumors of peripheral nerves • Schwannoma. Originated from the sheet of the intracranial segment of

cranial nerves, especially VIII (vestibulo-cochlear, vestibular part) - „Acustic neurinoma” „Cerebello-pontine angel tumor”.

• Usually localized to the intra-canalicular part of the nerve, later growing out, compressing brainstem. Slow growth, benign tumor.

• May be bilateral, esp. in m. Recklinghausen.

• Symptoms: worsening hearing loss, tinnitus (usually unilateral), vertigo, later, peripheral facial nerve palsy, after growing out the canal, brainstem or other cranial nerve signs.

• Dg: MR. Enhancing, round, circumscribed tumor along the course of the VIII. nerve. BAEP.

• Treatment: surgical or chemotherapy (for smaller tumors). Total recovery may be achieved.

Acustic neurinoma, MR with CM

Tumors originated from the meninges. • Meningiomas. In any age, but mainly in older persons, more frequent

in females. Very slow growth (20-30 years), but may reach extreme sizes. Rarely turns into malignancy. May destroy bones of skull.

• Originated from cells of the arachnoidea.

• May be anywhere on meninges, but there are typical sites:

• Fronto-basal (olfactory groove, Foster-Kennedy syndrome)

• Convexity. Sphenoid bone. Parasellar. Falx cerebri. Tentorium. Clivus.

• Spinal.

• Symptoms: depending on localisation. Epileptic seisures may occur. Dg: CT, MR. Strong CM enhancement, well circumscribed, calcificated, highly vascularized tumor, with no or sligh oedema.

• Widely attached to the meninges.

• Treatment: surgical, total removal if possible. Total recovery may be achieved.

Meningeoma

CT with CM MR with CM

Meningioma

Tumors of the hemopoietic system, affecting nervous system

• Primary nervous system lymphomas. B-cell, non-Hodggkin lymphoma. In immunsuppressed patients, mainly in AIDS.

• Dg: MR. Round-like, sometimes multiple lesions, usually close to CSF. Brain biopsy is necessary.

• Treatment: corticosteroids decrease the size of the tumors.

Pituitary tumors

• Pituitary adenomas. Originated from endocrine gland cells of the pituitary glands.

• Micro or macro-adenomas. Intra or suprrasellar masses.

• Hormonally active or inactive.

• Symptoms: local signs (visual field defect, etc.),

• hormonal dysfunction -

• Hyperfunction

– hyperprolactinaemia (galactorrhoea, amenorrhoea)

– GH overproduction (acromegaly, giant growth)

– ACTH overproduction (Cushing disease)

– TSH overproduction (central hyperthyreoidism)

• Hypofunction: decrease of one or all the upper hormones („panhypopituitarism”) Caused by compression of the functioning normal gland tissue.

Pituitary tumors • Dg: CT, MR. Microadenomas are non enhancing foci within the normal

gland Tissue.

• Macroadenomas are usually enhancing, irregular, masses, with extrasellar propagation.

• Treatment: surgical: transsphenoidal or by craniotomy.

• Irradiation.

• Hormonal treatment: bromocriptine may decrease the tumor size and normalize the hormonal dysfunction.

CT with CM

Metastatic brain tumors (from other parts of the body)

• In many cases the brain metastasis is diagnosed before the recognition of the primary tumor. Sometimes the origin is not found at all.

• Metastatis brain tumors, in order of frequency:

• Lung 64%

• Breast 14%

• Unknown origin 8%

• Malignant melanoma 4%

• Colorectal 3%

• Kidney 2%

• Others 5%

Metastatic brain tumors • Symptoms: nott differing from the general tumor-symptoms. • Focal epileptic seizures are quite frequent. • Dg: CT, MR: often multiple, round like, enhancing lesions with large

perifocal oedema. • Lumbar puncture (for diagosing meningeal spreading of the tumor „carcinous

meningitis”)• Brain biopsy. May provide information about the origin of the tumor. • Investigation of the primary tumor.

• Treatment: if solitary is the metastasis surgical removal is possible. In multiple cases irradiation ot chemotherapy. Outcome is dependent on the general oncologic state of the patient.

CT, no CM CT, with CM CT, with CM

Meaning of the lecture

• - Brain tumors are not frequent, but we have to consider them.

• - The symptoms of brain tumors are not specific.

• - New onset headache or epileptic seisures always indicate a search for brain tumor.

• _ Some types of brain tumors recognized in time have good outcome.

Thank you!