Circumscribed Astrocytic Gliomas Flashcards
Pilocytic astrocytomas are the most common astrocytic tumors in children which are WHO grade 1 tumor. The most common location for these tumors is cerebellar hemisphere. These are usually cured with complete surgical resection. What is the recommendation for postoperative radiotherapy in such tumors?
● A. It is never indicated
● B. Indicated for all postoperative cases
● C. Indicated for nonresectable recurrence
● D. C + used for malignant recurrence of tumor
● E. Depends on histopathological report
D. C + used for malignant recurrence of tumor
All of the following are differentiating points between pilocytic astrocytoma and pilomyxoid astrocytoma except?
● A. Pilocytic astrocytoma (PCA) shows biphasic compact and loose growth patterns while pilomyxoid astrocytoma (PMA) shows monomorphic pattern with loose cells
● B. PCA shows high proliferative index, while PMA shows low cellularity
● C. PCA may or may not have Rosenthal fibers and eosinophilic granular bodies while PMA often lack Rosenthal fibers and eosinophilic bodies
● D. PMA carries a higher rate of recurrence, worse outcome, and more tendency for CSF dissemination as compared to PCA
● E. PCA most commonly occurs in cerebellar hemisphere, while PMA occurs mostly in hypothalamic and chiasmatic regions
B. PCA shows high proliferative index, while PMA shows low cellularity
Which of the following statements regarding location of pilocytic astrocytoma (PCA) is incorrect?
● A. 42% of PCAs are found in cerebellum
● B. Percentage of PCAs in cerebral hemisphere is 35% and these most commonly occur in children
● C. Optic gliomas and hypothalamic gliomas constitute 9%
● D. PCAs arising in the optic nerves are called optic gliomas, and they are the most common site in neurofibromatosis type 1
● E. Percentage of brainstem PCAs is 9%
B. Percentage of PCAs in cerebral hemisphere is 35% and these most commonly occur in children
Feature of pilocytic astrocytoma (PCA) on CT or MRI is usually a contrast enhancing mural nodule (especially cerebellar PCAs) with cystic component with little or no surrounding edema. What is the recommended treatment option for PCA?
● A. Excision of nodule along with cyst wall in every case
● B. In tumors with false cyst where cyst wall also enhances, only cyst wall needs to be removed
● C. Both false cyst and mural nodule need to be removed
● D. Cyst wall does not need to be removed in any case
● E. Radiotherapy and chemotherapy are recommended in all postoperative cases
C. Both false cyst and mural nodule need to be removed
Pilocytic astrocytomas (PCAs) constitute 15% of primary brain tumors in patients aged less than 19 years and 27 to 40% of pediatric posterior fossa tumors. Optic pathway gliomas account for 2% of gliomas in adults and 7% in children. What is the most common location of optic pathway glioma in sporadic cases (other than in NF1)?
● A. Optic nerve
● B. Optic disc
● C. Optic chiasma
● D. Optic nerve with involvement of hypothalamus
● E. Both optic nerves simultaneously
C. Optic chiasma
A patient presents with nonspecific visual deficit without proptosis. This patient also has pituitary dysfunction and signs of hydrocephalus. MRI of brain shows mild to moderately enhancing chiasmal tumor. What is the recommended treatment
for optic pathway glioma tumors?
● A. Chiasmal tumors are good for biopsy only with CSF shunting and removal of exophytic component
● B. Tumors involving optic nerve are removed using transcranial approach with excision of nerve from the globe all the way back to the chiasma
● C. Transorbital (Kronlein) approach is not appropriate for optic nerve tumors since the tumor may be left in the nerve stump
● D. Radiotherapy and chemotherapy are recommended for chiasmal tumors, multicentric tumors, postoperatively if tumor is found in chiasmal stump end of resected nerve, and malignant tumor
● E. All of the above
E. All of the above
A young patient presents with macrocephaly, signs of hydrocephalus, cachexia, and diabetes insipidus. On imaging, a tumor involving the third ventricle and chiasmal region is found. What is the most probable diagnosis in this case?
● A. Chiasmal glioma
● B. Third ventricular tumor
● C. Hypothalamic glioma
● D. Brainstem glioma
● E. Optic nerve glioma
C. Hypothalamic glioma
Upper brainstem tumors are usually lower grade tumors and present with cerebellar findings and hydrocephalus while lower brainstem tumors are usually higher grade with signs and symptoms of multiple lower cranial nerve deficits and long
tract findings. Following are the patterns that can be identified on MRI in brainstem gliomas except?
● A. Diffuse gliomas, which are midline malignant, H3 k27 mutant, are seen mostly in pediatrics
● B. Cervicomedullary gliomas are mostly low-grade astrocytomas
● C. Ventrally exophytic brainstem gliomas are low-grade gliomas
● D. Focal gliomas are mostly limited to medulla and most are low-grade astrocytomas
● E. Dorsally exophytic gliomas may be low-grade gliomas
C. Ventrally exophytic brainstem gliomas are low-grade gliomas
Following statements are most appropriate regarding management of brainstem gliomas except?
● A. There is no role of biopsy in nonexophytic infiltrating brainstem gliomas
● B. Exophytic brainstem gliomas with broad attachment to the floor of 4th ventricle precludes complete excision, and survival can be increased in such cases with excision
● C. Surgery in malignant astrocytomas is without benefit; however, biopsy and shunting for hydrocephalus are recommended
● D. Tumors that demonstrate recurrent growth after resection remain histologically benign and are amenable to resection
● E. Radiations are given in 45 to 55 Gy dosage over a 6-week period, 5 days per week, and steroids added to radiotherapy can cause symptomatic improvement in 80% patients
A. There is no role of biopsy in nonexophytic infiltrating brainstem gliomas
A patient presents with diplopia, visual field deficits, nystagmus, Parinaud’s syndrome, ataxia, and seizures along with hydrocephalus. MRI of brain showed a mass projecting dorsally from the quadrigeminal plate. Diagnosis of tectal glioma is
made, which is also referred to as the smallest tumor in the body that can lead to death of the patient. What is the management option for these tumors?
● A. VP shunting
● B. Endoscopic third ventriculostomy
● C. Endoscopic aqueductoplasty
● D. Stereotactic radiosurgery
● E. All of the above
E. All of the above
A patient presents with history of seizures, and imaging showed a contrast enhancing lesion in temporal region with dural tail. On histopathology, astrocytes with pleomorphic tumor cells were found including large multinucleated cells, spindle cells, xanthomatous cells, and eosinophilic granular
bodies. What is the most probable diagnosis in this patient?
● A. Meningioma
● B. Pleomorphic astrocytoma
● C. Pleomorphic xanthoastrocytoma
● D. Subependymal giant cell astrocytoma
● E. None of the above
C. Pleomorphic xanthoastrocytoma
A young patient presents with signs and symptoms of raised ICP. Imaging showed a tumor arising from the walls of lateral ventricles next to foramen of Monro. Gross total resection of the tumor was done with everolimus given to reduce the tumor size and progression. This tumor has strong association with tuberous sclerosis. What is the most likely diagnosis in this patient?
● A. Choroid plexus papilloma
● B. Intraventricular meningioma
● C. Subependymal giant cell astrocytoma
● D. Chordoid glioma
● E. Astroblastoma
C. Subependymal giant cell astrocytoma
