Intracranial Tumors

1. Intracranial Tumors

2. Brain Tumors • Primary brain tumors occur in 6 persons per 100 000 per year. • In adults • 80-85% of the brain tumors localized in supratentorial region • 15-20% of the brain tumors localized in infratentorial region • Presentation: • progressive neurologic deficit (68%) • Headache (54%) • Seizures (26%)

3. Presentation of Supratentorial Tumors • Increased ICP • Progressive focal deficits • Headache • Seizures • Mental status changes • Symptoms suggestive of a TIA or stroke • Endocrine disturbances

4. Presentation of posterior fossa tumors • Increased ICP due to hydrocephalus. These include headache, nausea/ vomiting, papilledema, ataxia, vertigo, diplopia. • Lesions in cerebellum may cause ataxia, dysmetria, and intention tremor. • Brain stem involvement usually results in multiple cranial nerve and long tract abnormalities

5. WHO Classification of CNS Tumors (2007) • 1 Tumors of neuroepithelial tissue • 2 Tumors of cranial and paraspinal nerves • 3 Tumors of meninges • 4 Lymphomas and hemopoietic neoplasms • 5 Germ cell tumors • 6 Tumors of the sellar region • 7 Metastatic tumors

6. 1 Tumors of Neuroepithelial Tissue • 1.1 ASTROCYTIC TUMORS • Pilocytic Astrocytoma (Grade I) • Diffuse Astrocytoma (Grade II) • Anaplastic Astrocytoma (Grade III) • Glioblastoma (Grade IV) • 1.2. OLIGODENDROGLIAL TUMORS • Oligodendroglioma (Grade II) • Anaplastic Oligodendroglioma (Grade III) • 1.4. EPENDYMAL TUMORS • Ependymoma (Grade II)

7. 1 Tumors of Neuroepithelial Tissue • 1.5 CHOROID PLEXUS TUMORS • Choroid Plexus Papilloma (Grade I) • 1.8. PINEAL PARENCHYMAL TUMORS • Pineocytoma (Grade I) • Pineoblastoma (Grade IV) • 1.9. EMBRYONAL TUMORS • Medulloblastoma (Grade IV)

8. 1.1 Astrocytic Tumors(most common primary intra-axial brain tumors) • Pilocytic Astrocytoma (Grade I): • slow growing benign tumor • location: • optic gliomas & hypothalamic gliomas • brainstem gliomas • cerebellum • spinal cord • treatment of choice is surgical excision

9. 1.1 ASTROCYTIC TUMORS • Diffuse Astrocytoma (Grade II) • tend to occur in children and young adults • demonstrate low degrees of cellularity and preservation of normal brain elements within the tumor • surgery is the principal treatment • radiation is not indicated

10. 1.1 Astrocytic Tumors • Anaplastic Astrocytoma (Grade III): • occur in patients who are generally a decade older than those with an astrocytoma but a decade younger than those with a glioblastoma • duration of symptoms is usually shorter than that for the former lesion and longer than that for the latter • surgery followed by radiotherapy has become the standard • re-operation for recurrence extends survival

11. 1.1 Astrocytic Tumors • Glioblastoma (Grade IV): • the commonest primary brain tumor. It is also the most malignant of astrocytic tumors. • It occurs most commons in the cerebral hemisphere in the fifth decade or above • the symptoms of glioblastoma are usually of recent onset, and the patient is more ill • it has characteristic ring of contrast enhancement surrounds a center of low density, and has a zone of low density or edema around the ring enhancement • untreated glioblastomas is one of rapid progression • radical surgery followed by radiotherapy + chemotherapy is recommended • re-operation for recurrence extends survival

12. 1.2. Oligodendroglial Tumors • Oligodendroglioma (Grade II): • frequently presents with seizures • often calcified, predilection for the frontal lobes • comprises 4% of primary brain tumor • aggressive removal leads to longer survival. • Anaplastic Oligodendroglioma (Grade III): • surgery followed by chemotherapy is recommended

13. 1.4. Ependymal Tumors • Ependymoma (Grade II): • 5-6% of intracranial gliomas, mostly occurs in children • usually well circumscribed and benign, commonly arises in the floor of the fourth ventricle • comprises 25% of tumors in region of 4th ventricles • has potential to spread through CSF to spinal cord, a process known as seeding • mostly those of posterior fossa mass with increased ICP (headache, nausea and vomiting), ataxia or vertigo • goal of surgery is maximal possible resection without causing neurological deficits • total surgical resection of followed by craniospinal radiotherapy is recommended

14. 1.5 Choroid Plexus Tumors • Choroid Plexus Papilloma (Grade I): • 0.4-1% of all intracranial tumors • most of patients are <2 years old • it is histologically benign tumor • may become symptomatic because of the increased ICP produced by secretion of CSF • maybe cured surgically with total removal

15. 1.7 Neuronal and Mixed Neuronal-Glial Tumors • Paraganglioma (Chemodectoma, Glomus tumors) • histologically benign and slow growing tumors • arises from paraganglion cells, usually in the area of the jugular bulb, and tracks along vessels • a very vascular tumor with main feeders from ECA • patients commonly present with hearing lossand pulsatile tinnitus • combinations of palsies of cranial nerves IX, X, XI & XII occur with occasional VII palsy • radical surgical removal is recommended

16. 1.8. Pineal Parenchymal Tumors • Pineocytoma (Grade I): • a well-differentiated neoplasm arising from pineal epithelium • it can metastasize through the CSF and is radiosensitive • Pineoblastoma (Grade IV): • a malignant neoplasm arising from pineal epithelium • it can metastasize through the CSF, and is radiosensitive

17. 1.9. Embryonal Tumors • Medulloblastoma (Grade IV): • 15-20% of intracranial tumors in children, and is the most common malignant pediatric brain tumor • usually arises in the cerebellar vermis and predisposes to early obstructive hydrocephalus • usual presenting symptoms: headache, nausea and vomiting, ataxia • usually appears as a solid, midline, and IV-contrast-enhancing lesion on MRI • may disseminate via the CSF spontaneously or iatrogenically following surgery • prophylactic craniospinal radiotherapy is indicated following surgical removal • in children radiotherapy causes intellectual impairment and growth retardation and is avoided before 3 years of age

18. 2 Tumors of Cranial and Paraspinal Nerves • 2.1 SCHWANNOMA (Neurinoma) (Grade I) • slow growing, benign tumor • most arise from superior vestibular division of 8th nerve • 8-10% of intracranial tumors • incidence is 1 case per 100.000 population • 95% are unilateral • bilateral tumors being pathognomonic of NF2 • the incidence of VS is increased in NF2 • most common early symptoms are unilateral progressive hearing loss and tinnitus • otalgia, facial numbness and weakness, and taste changes occur as the tumor enlarges • larger tumors cause brain stem compression with ataxia, nausea and vomiting, diplopia, cerebellar signs, and lower cranial nerve palsies

19. 2 Tumors of Cranial and Paraspinal Nerves • 2.1 SCHWANNOMA (Neurinoma) (Grade I) • MRI is the diagnostic procedure of choice • round or oval enhancing tumor centered on internal acoustic meatus • all patients should have the detailed audiologic exam • total surgical excision is the treatment of choice for most tumors • for small tumors follow symptoms, hearing, and tumor size by serial MRI • intervention is recommended if growth > 2mm/year • total excision of tumor is the goal of surgery • facial nerve is pushed forward by the tumor and preservation of the facial nerve is very important • facial re-animation (hypoglossal-facial anastomosis) is performed after 1-2 months if VII was divided, or if no function returns after 1 year with an anatomically intact nerve

20. 3 Tumors of the Meninges • 3.1 TUMORS of MENINGOTHELIAL CELLS • Meningiomas: • 15% of primary intracranial tumors • slow growing, extra-axial circumscribed, usually benign tumors, which arise from arachnoid (not dura) • frequently calcified and often cause hyperostosis of adjacent bone • usually cured if completely removed • most commonly located along the parasagittal and falx, convexity, or sphenoid bone, however may occur anywhere that arachnoid cells are found • they can be asymptomatic • may be multiple in some of cases, this finding is more common in neurofibromatosis

21. 3 Tumors of the Meninges • 3.1 TUMORS of MENINGOTHELIAL CELLS • Meningiomas: • peak incidence at 45 years age, rarely occur in childhood and adolescence • occur with a higher incidence among women than among men • parasagittal and falx meningiomas up to half invade the superior sagittal sinus • plain x-rays may show calcifications within the tumor (in 10%), hyperostosis of the skull, enlargement of vascular grooves (especially middle meningeal artery) • MRI, appear as homogeneous, densely enhancing mass with broad base of attachment along dural border and dural tail is a common finding

22. 3 Tumors of the Meninges • 3.1 TUMORS of MENINGOTHELIAL CELLS • Meningiomas: • characteristically, it has external carotid artery feeders in angiography. Angiography also gives information about occlusion of venous sinuses • surgery is the treatment of choice for symptomatic meningiomas • incidental meningiomas may be managed expectantly with serial imaging, as meningiomas tend to grow slowly • extent of surgical tumor removal is the most important factor in the prevention of recurrence • radiotherapy reserve for malignant (invasive), aggressive, or non-resectable meningiomas

23. 3 Tumors of the Meninges • 3.4 OTHER NEOPLASMS RELATED to MENINGES • Hemangioblastoma: • it represents 1-2.5% of intracranial tumors • the most common primary intra-axial tumor in the adult posterior fossa • 20% occur as part of von Lippel-Lindau disease • it is histologically benign tumor • mostly cystic with a mural nodule and nodules are very vascular • surgical treatment may be curative

24. 4 Lymphomas and Hemopoietic Neoplasms • 4.1. MALIGNANT LYMPHOMAS • occur at any age • most frequently arise in the cerebral hemispheres, where, as contrast-enhancing masses • lesions usually enhance homogeneously without the typical ring of the glioblastoma • CNS involvement with lymphoma may occur secondarily from systemic lymphoma, or may arise primarily in the CNS • 10-30% of patients has multiple lesions • there is an almost diagnostic tendency of rapid partial to complete resolution on MRI following the administration of steroids, producing the so-called ghost tumor • the standard treatment after tissue biopsy is steroid therapy, chemotherapy and whole-brain radiation therapy • with no treatment, median survival is 2-3 months following diagnosis • 80% of cases recur, usually 15 months after treatment

25. 5 Germ Cell Tumors • occur principally in the pineal and suprasellar regions • almost all patients have hydrocephalus by the time of presentation • aside from benign teratoma, all intracranial GCTs are malignant and may metastasize via CSF and systemically • characteristically (but not always) give rise to tumor markers (ßhCG and AFP) in the CSF • germinomas are malignant tumors of primitive germ cells that occur in the gonads or in the CNS • survival with these is much better than with non-germinomas (embryonal carcinoma, choriocarcinoma, teratoma) • some of the pure germinomas are potentially curable with radiation therapy, but this is less likely for the other lesions, particularly the teratocarcinoma and choriocarcinoma

26. 6 Tumors of the Sellar Region • 6.1 CRANIOPHARYNGIOMA • benign tumors but difficulty in cure makes them malignant in behavior • 2.5-4% of all brain tumors • tend to arise from the pituitary stalk • almost all CP have solid and cystic components and calcification is very common • surgical approach is usually via pterional, or combined (transcallosal and pterional) • diabetes insipidus often develops postoperatively • postoperative mortality is 5-10% in most series, most from hypothalamic injury • post-op radiation probably helps prevent regrowth when residual tumor is left behind, however, in pediatric cases it may be best to postpone radiotherapy,recognizing that re-operation may be necessary for recurrence • morbidity/mortality is higher with re-operation

27. 7 Metastatic Tumors • most common sources of cerebral mets in adults are lung, breast, kidney • small cell Ca of the lung is more likely to produce cerebral mets • the highest incidence of parenchymal mets is located on the territory of MCA • solitary lesion in the posterior fossa of an adult is considered a metastasis until proven otherwise • usually appear as well circumscribed non-complicated masses on MRI • usually enhance in MR, and must be considered in the differential diagnosis of a ring-enhancing lesion • with optimal treatment, median survival is only 32 weeks, therefore management is mostly palliative

28. 7 Metastatic Tumors • medical management with radiation therapy without surgery is recommended for patients with multiple cerebral metastases, or widespread systemic cancer and obviously short life expectancy • initial treatment: anticonvulsants, corticosteroids • excisional surgery for solitary lesions is indicated when lesion accessible, lesion is symptomatic or life-threatening, primary tumor known to be relatively radioresistant, or diagnosis unknown • stereotactic biopsy maybe considered far deep lesions, in patients who are poor surgical candidates, to ascertain a diagnosis when another diagnosis is possible, or for multiple small lesions • radiation therapy is usually administered following surgery, where micrometastases are presumed to be present throughout brain

29. Pituitary Adenoma • arise primarily from the anterior part of the pituitary gland • represent 10% of intracranial tumors • most common in the 3rd and 4th decades of life, and equally affect both sexes • usually present either due to endocrinologic disturbance, or due to mass effect • divided into two groups: functional (secreting), and non-functional (non-secretory) • functional tumors frequently present earlier with symptoms caused by endocrinologic disturbances • non-functional tumors usually do not present until of sufficient size to cause neurologic deficits by mass effect

30. Pituitary Adenoma • panhypopituitarism may be caused by large tumors of the non-functional type • in large tumors optic chiasm may compressed (classically resulting in bitemporal hemianopsia) • in endocrinologic evaluation we have to check the adrenal axis, thyroid axis, gonadal axis, prolactin level, growth hormone, and neurohypophysis • lateral skull x-ray may help define anatomy of sphenoid sinus in cases where transsphenoidal surgery is planned • MRI is choice for pituitary adenomas • microadenoma (< 1 cm), macroadenoma (> 1 cm)

31. Pituitary Adenoma • Prolactinoma: • causes amenorrhea-galactorrhea syndrome in females, impotence in males, and often infertility in either sex • if no acute progression, these tumors may shrink dramatically on bromocriptine (dopamine agonist) • surgery is indicated if PRL >500 and tumor not controlled on bromocriptine • surgery followed by reinstitution of bromocriptine therapy may normalize PRL

32. Pituitary Adenoma • Acromegaly: • GH secreting tumors that cannot be managed medically • causes acromegaly in adults, and gigantism in prepubertal children • if no contraindications, transsphenoidal surgery is the best initial therapy • for patients not cured by surgery, or with recurrences after surgery, radiosurgery is indicated

33. Pituitary Adenoma • Cushing’s disease: • elevated ACTH causes endogenous hypercortisolism (Cushing’s disease) • long-term efficacy of medical therapy is inadequate • surgery is recommended

34. Pituitary Adenoma • transsphenoidal approach usually the procedure of choice (an extra-arachnoid approach, no external scar, and no brain retraction) • transsphenoidal approach indicated for microadenomas, macroadenomas without significant extension laterally beyond the confines of the sella and tumors with extension into sphenoid sinus • transcranial approaches (pterional) is useful for makroadenomas

35. Pituitary Adenoma • radiation therapy should not be routinely used following surgical removal of pituitary adenomas, followpatient with yearly MRI • treat recurrence with repeat operation • consider radiosurgery if recurrence cannot be removed and mass continues to grow

36. Pituitary Adenoma • Pituitary apoplexy • onset of neurologic deterioration usually consisting of headache, visual deficit, ophthalmoplegia, and reduced mental status • usually due to an expanding mass within the sella turcica as a result of hemorrhage, necrosis, or infarction within the tumor • CT or MRI shows hemorrhagic mass in sella and/or suprasellar region • emergency decompression to preserve vision is usually indicated

37. Chordoma • CHORDOMA • benign, slow growing, locally aggressive, and have a high recurrence rate • rare tumors of the remnant of the primitive notochord. • may arise at end of the notochord in the spheno-occipital region (clivus) • radical surgical removal is recommended

38. Cysts and Tumor-like Lesions • EPIDERMOID CYST • occur most frequently in the leptomeninges, especially those at the CPA and suprasellar region • comprise 1% of intracranial tumors, and 7% of CPA tumors • tend to spread along normal cleavage planes and surround vital structures • surgery is the essential treatment method

39. Cysts and Tumor-like Lesions • COLLOID CYST • occurs in the anterior 3rd ventricle • slow-growing benign tumor, and blocking foramina of Monro causing hydrocephalus • 0.5-1% of all intracranial tumors • acute blockage of CSF can cause sudden death • surgical removal is recommended