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Dr. Zana A. Mohammed M.B.Ch.B., F.I.B.M.S. Neurology Faculty of medical science School of medicine University of Sulaimaniah. Brain compartments. Brain tumor A brain tumor is a localized intracranial lesion which occupies space within the skull. Incidence of primary brain tumors
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Dr. Zana A. Mohammed M.B.Ch.B., F.I.B.M.S. Neurology Faculty of medical science School of medicine University of Sulaimaniah
Brain tumor A brain tumor is a localized intracranial lesion which occupies space within the skull.
Incidence of primary brain tumors • (benign or malignant) 12.8/100,000 • 10%–15% of cancer patients developbrain metastases
Often unknown • Risk factors: • Genetic changes • Family history • Errors in fetal development • Ionizing radiation • Environmental hazards (including diet) • Viruses • Injury or immunosuppression
Primary ( benign and malignant). • secondary (metastatic) • 35% - lung • 20% - breast • 10% - kidney • 5% - gastrointestinal tract • Location ( intra-axial and extra-axial)
Clinical features • There are three groups of symptoms and signs resulting from brain tumors: • Raised intracranial pressure • Epilepsy • Evolving focal neurological deficit.
Raised intracranial pressure The cardinal features of raised intracranial pressure are: • Headache • Vomiting • Papilledema • False localizing signs • Depression of conscious level • Signs of tentorial herniation and coning.
Headaches of raised intracranial pressure tend not to be • extremely severe, they are usually generalized throughout the head, and they tend to be worse in the mornings when the patient wakes. They sometimes wake the patient earlier than his normal waking time. • papilledema: The patient may report transient blurring or loss of vision. Such visual obscurations should stimulate urgent investigation and treatment.
False localizing signs We have seen that a mass lesion in one compartment of the brain can induce shift and compression in parts of the brain remote from the primary lesion producing false localizing signs. • The descent of the brainstem may stretch the 6th cranial nerve to produce a non-localizing lateral rectus palsy: • The ventricular dilatation above midline CSF obstructive lesions, or above posterior fossa lesions may produce: —intellectual and behavioral changes suggestive of primary frontal pathology; —an interference with vertical eye movements (upper midbrain) because of the dilatation of the posterior part of the 3rd ventricle and aqueduct
Epilepsy • Focal epilepsy, focal epilepsy progressing on to a generalized tonic–clonic seizure, tonic–clonic seizures with post-ictal focal neurological signs, and tonic–clonic epilepsy without any apparent focal features may all indicate the presence of a tumor in the cerebrum. • Epilepsy is not a feature of posterior fossa tumors. • Epilepsy is not commonly caused by tumors, and less than 50% of cerebral tumors produce epilepsy, but the occurrence of epilepsy in adult life should prompt the possibility of a brain tumor in the doctor’s mind.
Focal neurological deficit • The presence of a tumor impairs the function of the part of the brain in which it resides. The nature of the evolving focal neurological deficit clearly depends on the site of the lesion. • Tumors near the midline and in the posterior fossa may produce marked features of raised intracranial pressure before there are many localizing signs.
Gliomas • Astrocytoma (Grades I & II) • Anaplastic Astrocytoma • Glioblastoma Multiforme • Oligodendroglioma • Ependymomas • Medulloblastoma • CNS Lymphoma
Gliomasare seen to appear in both the benign and malignant groups of tumors. • Astrocytomas are by far the most common glial tumor; derived from oligodendrocytes, ependyma, neurons, primitive neuroectodermal or other tissues are much rarer. • Gliomas are classified histologically from grade 1 (benign) to grade 4 • (the highly malignant glioblastoma multiforme). • Benign gliomas are, unfortunately, much less common than malignant ones and have a tendency to become more malignant with time.
Grade I • Non-infiltrating
Grade II Infiltrating Slow growing
Grade III • Infiltrating • Aggressive
Grade IV • Highly infiltrative • Rapidly growing • Areas of necrosis
Grades II-IV Mixed astro/glio
Slow growing Benign HCP/ICP Surgery, RT, Chemo
Small cell embryonal neoplasms Malignant HCP/ICP
Primary CNS lymphoma • B lymphocytes • Increased ICP • Brain destruction
Meningioma • Metastatic • Acoustic neuromas (Schwannoma) • Pituitary adenoma • Neurofibroma
Meningioma • Nearly always benign. • They may arise from any part of the meninges, over the surface of the brain, from the falx, or from the tentorium. • There is a plane of cleavage between tumor and brain tissue which makes total removal a definite possibility.
Usually benign • Slow growing • Well circumscribed • Easily excisable
Benign tumors of the Schwann cells • Located in CP angle and the internal auditory meatus in the petrous temporal bone. • produce progressive unilateral nerve deafness, associated 5th and 7th nerve dysfunction, unilateral cerebellar signs and evidence of raised intracranial pressure. • Early diagnosis is critical
Benign • Anterior pituitary • Endocrine dysfunction • chiasmatic compression • Bitemporal hemianopia
Pituitary adenomas • Space-occupying effects: • suprasellar extension to compress optic nerves/chiasm/tracts. Bitemporal hemianopia resulting from chiasmal compression. so monocular blindness due to optic nerve compression and homonymous hemianopia from optic tract compression according to location of pituitary gland. • Lateral expansion may compress structures on the lateral wall of the cavernous sinus (cranial nerves, 3, 4, 5a and 6), producing double vision and forehead numbness. • Forward and downward expansion of the adenoma results in enormous expansion of the pituitary fossa and occasional erosion through bone into the sphenoidal air sinus.
2. The endocrine disturbances that accompany the development of a pituitary adenoma are: • Positiveif the tumor cells are secretory (prolactin, growth hormone, etc.) • Negativeif the tumor is preventing normal secretion by the rest of the pituitary gland (varying degrees of pan hypopituitarism).
Cystic tumor coming from remnant of Rathke’s pouch • Hypothalamic-pituitary axis dysfunction
Peritumoral edema Necrotic center
80% of metastases occur supratentorially and 20% infratentorially (distribution of cerebral blood supply) • Up to 75% of patients have neuroimaging evidence of multiple metastases at presentation • Lung cancer and melanoma are most likely to produce multiple metastases • Renal cell carcinoma, breast cancer, and colon cancer are most likely to produce single brain metastasis • Retroperitoneal, pelvic, gastrointestinal primary tumors have predilection for posterior fossa
Metastasis occurs with hematogenous spread and typically land at gray matter white matter junction because of abrupt change in blood vessel caliber. • Except for certain neoplasms such as malignant melanomas that can penetrate arterial (arteriolar) walls and are often hemorrhagic, most tumors usually penetrate capillary beds to arrive at their destination
Radiological Imaging • Computed Tomography scan (CT scan) with/without contrast • Magnetic Resonance Imaging (MRI) with/without contrast • Plain films • Myelography • Positron Emission Tomography scan (PET scan) • LP/CSF analysis • Pathology
Resection Craniotomy Stereotaxis Surgery Biopsy Transsphenoidal
Drug therapy – Palliative • Done for symptom treatment and to prevent complications • NSAIDs • Analgesics • Steroids (Decadron, medrols, prednisone) • Anti-seizure medications (phenytoin) • Histamine blockers • Anti-emetics • Muscle relaxers (for spasms) • Mannitol for ICP –New Hypertonic saline
Wound infection • Seizures • CSF leak • Edema • Increased ICP • Hematoma • Hypovolemic shock • Hydrocephalus • Atelectasis • Pulmonary edema • Meningitis • Fluid and electrolyte imbalances (ADH)
Damages DNA of rapidly dividing cells • 4000–6000 Gy total dose • Duration of 4–8 weeks
Slows cell growth • Cytotoxic drugs • CCNU, BCNU, PCV, Cisplatin, Etoposide, Vincristine, Temozolomide (Temodar)
A patient is being directly admitted to the medical-surgical unit for evaluation of a brain mass seen in the frontal lobe on a diagnostic CT scan. Which of the following signs and symptoms would the patient most likely present with? • Personality changes • Visual field cuts • Difficulty hearing • Difficulty swallowing
Case 1 A 65-year-old widow presents with a 6-month history of unsteadiness. She has started to veer to the left. She has been well prior to this, apart from a longstanding hearing problem and surgery for colon cancer 5 years ago. On examination she has an ataxic gait, slight leftwards nystagmus, an absent left corneal reflex and marked left-sided deafness. There is no papilledema. a. What do you think is the cause of her symptoms?
Case 2 A 45-year-old oil company executive returns from secondment in Nigeria because of ill health. Over the last 3 months he has become slow and erratic, making frequent mistakes at work and getting lost on his way home. His memory has become poor and he has had difficulty in finding his words. His appetite has faded and he has lost weight. In the last 2 weeks he has become unsteady on his feet and incontinent of urine. On examination he is thin. He has no fever but his axillary and inguinal lymph nodes are slightly enlarged. He is drowsy. He had bilateral papilledema. He has difficulty cooperating with a neurological examination and becomes increasingly irritated when you persist. a. What do you think is the cause of his symptoms?