TUMORS2 Flashcards
Almost ______ of all leukemic patients have evidence of diffuse infiltration of the leptomeninges and cranial and spinal nerve roots at autopsy
one-third
The incidence is greater in acute than in chronic leukemia and greater in ______ than in myelocytic leukemia
lymphocytic
The highest incidence of involvement of CNS is in children with _______ who relapse after treatment with combination chemotherapy (60 to 70 percent at time of death)
acute lymphocytic (lymphoblastic) leukemia
The studies of Price and Johnson demonstrated that CNS leukemia is primarily a ________. The earliest evidence of leukemia is detected in the walls of pial veins, with or without cells lying freely in the CSF
pial disease
_______ and __________ given intrathecally or intravenously; has been effective in the prevention and treatment of meningeal involvement in childhood leukemia
Cranial radiation, combined with methotrexate
Cx of chemoRT after tx of meningeal involvement in childhood leukemia
necrotizing leukoencephalopathy within several days to months after the last administration of methotrexate and several months after completion of radiotherapy
MRI findings of necrotizing leukoenceph vs radiation necrosis
On MRI these lesions appear T2 hyperintense, but compared with pure radiation necrosis (see further on), they have poorly demarcated borders and like on CT, do not enhance
__________ o f the spinal cord o r cauda equina is the most common neurologic complication of all types of lymphoma, the result of extension from vertebrae or paravertebral lymph nodes
Extradural compression
In the rare cases of meningeal involvement with _______, there may be an eosinophilic pleocytosis
Hodgkin lymphoma
These are malignant tumors composed of cells derived from connective tissue elements (fibroblasts, rhabdomyocytes, lipocytes, osteoblasts, smooth muscle cells
S a rc o m a s of t h e B ra i n
_______ have occurred after radiation of pituitary adenomas and osteogenic sarcoma after other types of radiation, all localized to bone or meninges.
Fibrosarcomas
_________is an invasive and rapidly growing tumor, mainly of childhood, that arises in the posterior part of the cerebellar vermis and neuroepithelial roof of the fourth ventricle in children
Medulloblastoma
Origin of Medulloblastoma
The current view of the tumor is that it originates from pluripotential stem cells (that can differentiate into neuronal or glial elements) that have been prevented from maturing to their normal growth-arrested state
Certain molecular genetic similarities relate the medulloblastoma to _________, ____________ and, rarely, to autosomal dominant diseases such as ________
retinoblastomas and pineal cell tumors, nevoid basal cell carcinoma.
Chromosomal studies of medulloblastomas reveal a deletion on the distal part of chromosome _______ distal to the p53 region.
1 7
It is also notable that medulloblastomas are encountered in ______, caused by mutations in the gene encoding “patched,” the receptor for sonic hedgehog ligand, and in ________, as a consequence of mutations in DNA repair genes
Gorlin syndrome Turcot syndrome
In Medulloblastoma: Gene expression profiling has given preliminary evidence that amplification or overexpression of the transcription factor ________ is associated with a poorer prognosis (as it is in neuroblastoma)
MYCN (N-MYC)
In Medulloblastoma, The majority of the patients are children ______years of age, and males outnumber females_______ in most reported series
4 to 8 3:2 or 3:1
In Medulloblastoma,
The radiologic appearance is also distinctive: high signal intensity on both Tl- and T2-weighted MRis, heterogeneous enhancement, and, of course, the typical location adjacent to and extending into the fourth ventricle
________ of the tumor is recommended. The addition of________ and ________ of the entire neuraxis improves the rate and length of disease-free survival even for those children with the most extensive tumors at the time of diagnosis
Maximal resection chemotherapy and radiotherapy
In Medulloblastoma, The combination of surgery, radiation of the entire neuraxis, and chemotherapy permits a 5-year survival in more than______ percent of cases
80
In Medulloblastoma, The presence of__________ (i.e., connective tissue formations) is associated with a better prognosis independent of the type or treatment
desmoplastic features
In Medulloblastoma, Any of the features of _______, ________, _______ greatly reduce the period of survival.
brainstem invasion, spinal subarachnoid metastases, incomplete removal, and very early age of onset (younger than 3 years)
This, the most common solid tumor of childhood, is a different entity from medulloblastoma but of nearly identical histologic appearance, arising in the adrenal medulla and sometimes metastasizing widely.
Neuroblastoma
Paraneoplastic complication of NB
polymyoclonus with opsoclonus and ataxia
T or F A rare form of neuroblastic medulloblastoma in adults tends to be more benign
T
Poor prognosticating factors in NB
- loss of heterozygosity of certain sites on chromosomes 1 and 11 2. MYCN amplification or overexpression 3. polymorphisms in chromosome 6p`
Treatment of NB low intermediate high
Treatment is predicated on clinical staging, with the lowest risk category allowing observation because some lesions regress spontaneously. Those patients who are at intermediate risk are treated with chemotherapy and high risk children have surgical resection and receive intensive chemotherapy, radiation, and in selected cases, hematopoietic stem cell transplantation
SR of patients with NB
survival rates exceeding 90 percent, but the highest risk group has a 30 percent survival rate
This proves to be one of the most frequent extracranial malignant tumors of infancy and childhood
RB
It is a small cell tumor with neurofibrils and, like neuroblastoma, has a tendency to form rosettes.
RB
Whereas the supratentorial ependymoma occurs at all ages, _____ ependymomas appear mostly in childhood.
fourth ventricular
The most anaplastic form of ependymoma is the _______________, a highly aggressive tumor that falls within the spectrum of primitive neuroectodermal tumors
ependymoblastoma
Locations of choroid plexus papilloma
They arise mainly in the lateral and fourth ventricles, occasionally in the third.
Molecules associated with tumor induction in choroid papilloma
T (tumor) antigen of the SV40 virus is possibly involved in tumor induction
MRI appearance of hemangioblastoma
The diagnosis can be deduced from the appearance on CT or MRI of a cerebellar cyst containing an enhancing nodular lesion on its wall
Angio of HB
The angiographic picture is also characteristic: a cluster of small vessels forming a mass 1 .0 to 2.0 em in diameter
Hemangioblastomas of the spinal cord are frequently associated with a _________ (greater than 70 percent of cases);
syringomyelic lesion
four types of pineal tumors
germinoma, nongerminatous germ cell tumors, pinealoma (pineocytoma, atypical pineocytoma, and pineoblastoma), and a glioma originating in astroglial cells of the pineal body
Of the four groups of pineal tumors, approximately 50 percent are _______
germinomas
Cytologically, the __________ is a moderately cellular tumor with none of the histologic attributes of anaplasia.
pineocytoma
T or F, pineocytoma forms rosettes
The tumor cells tend to form circular arrangements, so-called pineocytomatous rosettes
__________ are highly cellular and composed of small, undifferentiated cells bearing some resemblance to medulloblasts
Pineoblastomas
In patients with a germ cell tumor, the CSF or serum may show elevations of ______ or ________
B-human choriogonadotropin or alpha-fetoprotein