Download SDL 13- Brain Tumors II Ganglioglioma Well differentiated, slowly

SDL 13- Brain Tumors II
Ganglioglioma
Well differentiated, slowly growing neuroepithelial tumor composed of neoplastic, mature ganglion cells
Alone- gangliocytoma (WHO grade I)
In combo with neoplastic cells- ganglioglioma (WHO grade I or II)
Anaplastic gangliogliomas: show anaplastic features in their glial component and are considered WHO III
Gangliocytoma and ganglioglioma: 0.4% of all CNS tumors
2 months to 80 years of age
Cerebrum (seizures), brainstem, cerebellum, SC
Majority are supratentorial in temporal lobe
Most common tumors associated with chronic temporal lobe epilepsy
Large, pink cells: mature-appearing ganglion cells
Dysembryoblastic Neuroepithelial Tumor (DNET)
Benign glial-neuronal neoplasm, usually supratentorial occurring primarily in a cortical location
Occur in children and young adults with long-standing history of partial seizures
0.8-5% of all surgical resections for seizures (majority n temporal lobe with mesial structures)
WHO grade I
2nd to 3rd decades of life diagnosis
Males more commonly affected than females
Long-standing, drug resistant partial seizures before age 30
Histologically: glioneural element with columns of cells oriented perpendicular to the cortical surface (normal cytology in
a pale, eosinophilic matrix between columns)
Central Neurocytoma
Conformed of uniform round cells with neuronal differentiation typically inn lateral ventricles and Foramen of Monro
Primarily affects young adults, favorable prognosis
Tumor corresponds histologically to WHO grade II
Large surgical cases, incidence from 0.25-.5% of all intracranial tumors
Mean age 29 years (8-67 range)
Increased ICP visual and mental disturbances
Hormonal dysfunction associated with neurocytoma of septum, third ventricle, hypothalamus
Usually benign, local recurrances reported
Treatment of choice for this tumor is complete surgical resection
Gray, friable with varying calcifications and occasional hemorrhage
Neuroepithelial tumor composed of uniform, round cells that show immunohistochemical and ultrastructural features of
neuronal differentiation
Rarely associated with von Hippel-Lindau disease
Medulloblastomas
Malignant cerebellar tumor of undifferentiated neural cell precursors accounting for 60% primary CNS tumors in child
Classified as embryonal tumors (undifferentiated, infratentorial)
Primarily in cerebellum ataxia, gait, increased ICP
High grade tumors with propensity to disseminate through CNS axis
Usually children in 1st decade
Soft, circumscribed areas with necrosis and hemorrhage
Small blue cells with minimal cytoplasm and high nuclear cytoplasmic ratios, mitotic activity, apoptosis
Homer-Wright rosettes in 1/3 of bases
Chromosome 17 and more commonly chromosomes 1,7, 10
CT (enhancing mass with cystic or necrotic foci) and MRI (decreased density or isodensity on T2) helpful in evaluation
Enhance with Gadolinium
50-85% five year survival rate
SDL 13- Brain Tumors II
Atypical Teratoid/Rhabdoid tumor (ATRT)
Malignant embryonal CNS tumor in children, composed of rhabdoid cells (resemble primitive skeletal muscle cells)
2% CNS tumors in patients 18 and less (generally <5 years)- male:female is 1.4:1
50% in posterior fossa, rest in supratentorial location
Many patients have disseminated tumor within the cerebrospinal fluid at the time of presentation
Infants have non-specific signs of lethargy, vomiting and/or failure to thrive
Headache and hemiplegia more common in children >3
Grossly, soft and pin-red in color resembling the gross features of medulloblastoma
Necrotic and hemorrhagic
Occur in cerebellopontine angle wrap around CN and vessels and invade the brainstem and cerebellum
Rhabdoid cells usually with variable components of primitive neuroectodermal tissue, mesenchyme, epithelium
Eosinophilic cytoplasm to be filled with vimentin intermediate filaments
Monosomy chromosome 22, gene hSNF5/INI-1 mapped to 22q11.2
Most patients die within one year of diagnosis
Primary CNS Lymphoma
Extranodal malignant lymphomas arising without evidence of other tumors
2-12% of AIDS patients
60% primary CNS lymphomas involve supratentorial space with the frontal lobe being the most common site
May occur after an organ transplant
Up to 40% spread to leptomeninges
Slight male:female ratio of 3:2
Majority of patients present with focal neurologic deficits including neuropsychiatric sx, increased ICP and seizures
Hyperdense or isodense lesions
Better prognosis with single lesion and absence of meningeal or periventricular tumor
Current therapy: radiation and chemotherapy
5 year survival rate: 45% (may be responsive to steroids)- if immunocompromized its less than 1 year
Single or multiple masses that are firm, firable, or focally necrotic and hemorrhagic
Obvious proliferation of dyscohesive, diffusely infiltrating atypical lymphoid cells
Majority: large B cell lymphomas (2% T cell origin)
Hodgkin’s disease is rare in CNS
Germ Cell Tumors
Primarily affect children and adolescents (10-12)
Homologous germ cell neoplasms arising in gonads and mediastimum
Germinoma, embryonal carcinoma, yolk sac tumor, choriocarcinoma, mature teratoma, immature teratoma, malignant
Western world: 0.5% of all primary intracranial neoplasms and 3% in childhood and adolescence
More prevalent in Asia: 2% of all primary intracranial neoplasms (9-15% of pediatric cases)
M:F is 2.5:1 (males: in pineal region; females: suprasellar germ cell tumors)
Mainly midline tumors with 0% of tumors arising in structures above the 3rd ventricle
Solid consistency, may show scattered cysts
Choriocarcinomas: can show areas of hemorrhage
Teratomatous cysts: often contain mucus
Rarely contain teeth and hair like in mature teratomas of ovaries
Germinoma: primitive germ cells with large nuclei and clear-appearing cytoplasm. Increased numbers of lymphocytes
Teratoma: recapitulate somatic development from the three embryonic germ layers. Mature teratomas are composed
of fully-differentiated “adult-type” tissue such as skin, hair, etc. Teratoma may express high levels of alphafetoprotein. Some teratomas may show malignant transformation.
Yolk sac tumor: composed of primitive cells putatively representing yolk sac endoderm embedded within a gray-blue
staining matrix. Eosinophilic hyaline globules immunoreactive for AFP are a diagnostic feature.
SDL 13- Brain Tumors II
Embryonal carcinoma: composed of large cells that proliferate in cohesive nests and sheets. Tumor cells have
prominent nucleoli, a high mitotic rate, and areas of necrosis.
Choriocarcinoma: this tumor is characterized by extra-embryonic differentiation along trophoblastic lines. The diagnosis
requires identification of cytotrophoblastic elements and syncytiotrophoblast giant cells. Cytotrophoblasts express HCG
(human chorionic gonadotropin).
Pure germinoma has favorable prognosis with radiosensitivity
Pineal tumors
Pineoblastoma
Malignant, poorly defined embryonal neoplasm
Metastasis via CSF may be fatal
Usually in first 2 decades of life, slight male predominance
Grossly poorly demarcated and may be associated with hemorrhage and necrosis
May infiltrate meninges
Patternless sheets of densely packed small cells with round to irregular nuclei and scant cytoplasm
Homer-Wright and Flexner-Wintersteiner rosettes may be seen
Pineocytoma
Slowly growing with either neuronal, glial, melanocytic, photoreceptor, and mesenchymal differentiation
Generally favorable prognosis
May compress adjacent structures (cerebral aqueduct, brainstem, cerebellum)
Symptoms related to increased ICP; visual disturbances, change in mental status
Well circumscribed tumors with small, uniform cells resembling pineocytes growing in sheets (high nuclear:cytoplasm)
Cellular rosettes may also be seen
5-year patient survival rate is 90%
Meningioma
Slow growing dural based tumors derived from meningothelial (arachnodi cap) cells
25% primary intracranial neoplasms
May arise proximal to dura withing the intracranial, orbital, and IV cavities
Most common in parasagittal region, cavernous sinus, foramen magnum
Slight female predominance, any age (commonly middle aged and elderly 60-70)
Focal neural deficits with increased ICP and seizures
May cause hyperostosis of overlying skull
Radiologic: circumscribed and show evidence of calcification, bone and cartilage
Curable by gross total resection, atypical forms have a tendency to recur
Morphologic: tumors are dural based and sharply demarcated and have rubbery or firm consistency
Microscopically: monomorphic cells arranged in a syncytium, nuclei are oval to round with intranuclear pseudoinclusions
Psammoma bodies (calcifications) are not uncommonly seen
Deletion of NF2 gene on chromosome 22q; occur in up to 60% of sporadic tumors
Metastatic Tumors
Most common tumors affecting CNS )(24% of cancer patients
Most are carcinomas (lung and breast)
Less common neoplasms are malignant melanoma, choriocarcinoma, renal cell carcinoma
65+ years old generally
Frequently seen in brain parenchyma and dura (80% in arterial border zones; 15% cerebellum)
Headache, focal weakness, papilledema
SC metastasis associated with evidence of cord compression (back pain, weakness in limbs, sensory disturbances)
Grossly: discrete, round or confluent and well-circumscribed masses of white-gray color
SDL 13- Brain Tumors II
Show hemorrhagic metastases: metastatic melanoma, choriocarcinoma, lung and renal cell carcinomas
Attached to dura and leptomeninges: may form plaques or nodules
Most common SC metastasis: breast carcinomas (22%) and lung (15%)
Metastatic malignant melanoma may demonstrate scattered black-brown CNS nodules (melanin)
Cancer patients with CNS lesions can undergo biopsy to determine metastasis
Histologic appearance depends on type of tumor present
Paraneoplastic Syndromes Involving CNS
Damage to organs or tissues that are remote from the site of malignant neoplasm or its metastases
Generally immune related (antibodies in patients serum and CSF)
Affect only a single area or cell type of CNS
Multiple levels might be affected
Exam of CSF reveals mild pleocytosis, slightly elevated protein level, elevated IgG levels
Tumor antigen is identical to the neural antigen, somehow the body id’s as foreign and mounts immune response
Examples:
1.
Paraneoplastic encephalomyelitis & paraneoplastic cerebellar degeneration: anti-Hu antibodies seen in patients with
small cell carcinoma, for example. Anti-CV2 antibodies in patients with small cell carcinoma are also associated with
encephalomyelitis and cerebellar degeneration.
2.
Ataxia with or without opsoclonus-myoclonus (opsoclonus is defined as involuntary rapid twitching of the eyes and
myoclonus is involuntary twitching of a muscle or group of muscles): anti-Ri antibody seen in patients with breast,
gynecologic, lung and bladder carcinomas.
3.
Visual syndromes (cancer associated retinopathy and optic neuritis): anti-retinal antibodies seen in patients with small
cell carcinoma of the lung, malignant melanoma, and gynecologic malignancies.
Treatment: removal of source of antigen by treatment of underlying tumor and suppression of immune response
Plasma exchange and IV immunoglobin (IVIG) are useful in suppression
Ependymoma
Well circumscribed malignant glioma with primarly ependymal features
9% primary brain tumors, 12% in children, 30% in infants
Most common glioma of SC (60%)
Posterior fossa in children , SC in adults
Symptoms depend on location
Posterior fossa: cerebellar ataxia, obstructive hydrocephalus, increased ICP with headache, N/V
Radiology: enhancing solid well demarcated mass (possible cystic feature, calcification and hemorrhages)
Prognosis: depends on success of surgical resection
Worst prognosis: children age 3 and younger
Feature: perivascular pseudorosetting
Nuclei round to oval with small nuclei, hypercellularity, frequent mitosis and endothelial hyperplasia WHO III
NF2 gene mutations are common in spinal (not intracranial ependymomas)
Loss chromosome 22q and gain 1q
Hemangioblastoma
Uncertain histogenesis (2% intracranial tumors)
Slight male predominance in association with von-Hippel-Lindau syndrome (increased risk renal cell carcinoma)
Occur at a younger age (Increased risk of multiple tumors)
Good prognosis, curable with gross total resection
Well circumscribed, possible cyst, increased lipid content gives bright yellow appearance
Capillary asculature and stromal cells with vacuolation and lightly eosinophilic cytospasm
Mitoses and necrosis unusual
Most commonly arises within cerebellum (maybe brainstem, SC, supratentorium)
SDL 13- Brain Tumors II
Summary: Distribution of CNS Tumors and DDx
Although not an exhaustive list, anatomic location and age can be very helpful in forming a differential diagnosis for
brain tumors:
Cerebral Hemispheres
Adults: astrocytoma, glioblastoma, meningioma, metastatic carcinoma, oligodendroglioma, lymphoma
Children: astrocytoma, ependymoma, embryonal tumor
Lateral Ventricle
Adults: ependymoma, choroid plexus papilloma
Children: ependymoma, choroid plexus papilloma
Third ventricle
Adults: colloid cyst, ependymoma
Children: ependymoma, choroid plexus tumor
Pineal region
Adults & children: germ cell neoplasm, pineoblastoma/pineocytoma, glioma
Cerebellopontine angle
Adults: acoustic schwannoma, meningioma, choroid plexus papilloma
Children: ependymoma
Cerebellum
Adults: Hemangioblastoma, metastatic carcinoma, astrocytoma
Children: medulloblastoma, astrocytoma
Fourth Ventricle
Adults and children: ependymoma, choroid plexus papilloma