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Marc K Rosenblum

Publications and source records attributed to Marc K Rosenblum.

At least 19 recordsLinked to original sources
PubMed2006

Atypical teratoid/rhabdoid tumor evolving from an optic pathway ganglioglioma: case study.

We report an atypical teratoid/rhabdoid tumor arising in a ganglioglioma from an 11-year-old male who had been treated over a nine-year period. A combined histologic, immunohistochemical, and molecular genetic analysis confirmed this diagnosis. Molecular genetic studies demonstrated a mutation in exon 9 of the INI1 gene in the tumor, which was not present in the patient's blood. This report is the first to describe progression of a ganglioglioma to atypical teratoid/rhabdoid tumor.

Amino Acid Sequence↗
PubMed2005

Primary chordoid meningioma of lung.

Primary meningiomas of the lung are rare. Most pulmonary meningiomas are typical syncytial or transitional meningiomas with smaller numbers of fibrous-type tumors. Herein, we report an unusual pulmonary tumor with the microscopic, immunohistochemical, and ultrastructural characteristics of a chordoid meningioma. The tumor was composed of cords and fascicles of small- to medium-sized spindle and epithelioid cells with eosinophilic cytoplasm and round nuclei with finely dispersed chromatin. The tumor cells were surrounded by an abundant mucoid, vacuolated stroma. The periphery of the tumor was enveloped by a significant lymphoplasmacytic infiltrate. The neoplastic cells were positive for vimentin and epithelial membrane antigen only. The unusual morphology of the tumor caused significant diagnostic difficulties. The differential diagnosis included inflammatory myofibroblastic tumor, spindle cell myoepithelioma, and extraskeletal myxoid chondrosarcoma. To the best of our knowledge, this is possibly the first description of an extracranial or intrapulmonary chordoid meningioma.

Diagnosis, Differential↗
PubMed2005

Allelic losses at 1p36 and 19q13 in gliomas: correlation with histologic classification, definition of a 150-kb minimal deleted region on 1p36, and evaluation of CAMTA1 as a candidate tumor suppressor gene.

PURPOSE: Allelic loss at 1p is seen in 70% to 85% of oligodendrogliomas (typically in association with 19q allelic loss) and 20-30% of astrocytomas. Because most 1p deletions in gliomas involve almost the entire chromosome arm, narrowing the region of the putative tumor suppressor gene has been difficult. To better define the histologic correlates of different patterns of 1p and 19q loss, we evaluated 1p/19q status in a large group of gliomas. This also allowed us to define a very small minimal deleted region (MDR) on 1p36. EXPERIMENTAL DESIGN: Among 205 consecutive cases of glioma studied for 1p loss of heterozygosity (LOH), 112 tumors were evaluated for both 1p and 19q LOH using at least three polymorphic markers on 1p and 19q each. The latter group included both low-grade tumors (oligodendroglioma, diffuse astrocytoma, and "oligoastrocytoma") and high-grade tumors (anaplastic oligodendrogliomas, anaplastic astrocytomas, anaplastic oligoastrocytomas). Tumors with small segmental 1p losses (defined as LOH at some loci with retention of heterozygosity at other loci) were studied using a more extensive panel of markers to define the 1p MDR. The candidate gene was screened for mutations and its expression was studied by qualitative and quantitative reverse transcriptase-PCR and Northern blotting. RESULTS: Allelic losses on 1p and 19q, either separately or combined, were more common in classic oligodendrogliomas than in either astrocytomas or oligoastrocytomas (P < 0.0001). Classic oligodendrogliomas showed 1p loss in 35 of 42 (83%) cases, 19q loss in 28 of 39 (72%), and these were combined in 27 of 39 (69%) cases. There was no significant difference in 1p/19q LOH status between low-grade and anaplastic oligodendrogliomas. In contrast, no astrocytomas and only 6 of 30 (20%) oligoastrocytic tumors had combined 1p/19q loss. Although rare, 1p deletions were more often segmental in astrocytomas (5 of 6, 83%) than in oligodendrogliomas (3 of 35, 9%; P = 0.006). Eleven tumors (6 oligodendrogliomas or having oligodendroglial components, 5 purely astrocytic) with small segmental 1p losses underwent further detailed LOH mapping. All informative tumors in the oligodendroglial group and 2 of 3 informative astrocytomas showed LOH at 1p36.23, with a 150-kb MDR located between D1S2694 and D1S2666, entirely within the CAMTA1 transcription factor gene. Mutation analysis of the exons encoding conserved regions of CAMTA1 showed no somatic mutations in 10 gliomas, including 6 cases with and 4 cases without 1p LOH. CAMTA1 is normally expressed predominantly in non-neoplastic adult brain tissue. Relative to the latter, the expression level of CAMTA1 was low in oligodendroglial tumors and was further halved in cases with 1p deletion compared with those without 1p deletion (Mann-Whitney, P = 0.03). CONCLUSIONS: Our data confirm the strong association of combined 1p/19q loss with classic oligodendroglioma histology and identify a very small segment of 1p36 located within CAMTA1 that was deleted in all oligodendroglial tumors with 1p LOH. This MDR also overlaps the neuroblastoma 1p36 MDR. CAMTA1 shows no evidence of inactivation by somatic mutations but its expression is reduced by half in cases with 1p LOH, suggesting that the functional effects of CAMTA1 haploinsufficiency warrant further investigation.

Adult↗
PubMed2005

Necrotizing vasculopathy of the CNS: case report.

A 62-year-old man with progressive cerebellar and brainstem dysfunction had gadolinium-enhancing lesions in basal ganglia and occipital lobe on MRI suggestive of primary CNS lymphoma (PCNSL). The patient, who had been treated with high-dose steroid hormones for several months, developed respiratory failure and expired before a histological diagnosis could be obtained. The postmortem examination showed Pneumocystis cariniiwas the cause of death. Pathology of the brain showed a necrotizing vasculopathy affecting the white matter of the cerebrum and cerebellum with involvement of the basal ganglia and the periventricular gray matter. Other organs such as liver, lung, and kidneys were spared. Necrotizing vasculopathy is a novel entity that should be considered in the differential diagnosis of PCNSL.

Brain Neoplasms↗
PubMed2005

INI1 protein expression distinguishes atypical teratoid/rhabdoid tumor from choroid plexus carcinoma.

Central nervous system atypical teratoid/rhabdoid tumor (AT/RT) and choroid plexus carcinoma (CPC) are rare, highly malignant tumors that predominantly arise in infants and young children. Overlapping clinical, histologic, ultrastructural, or immunophenotypic features may obscure the diagnosis in some cases. AT/RT is characterized by deletions and/or mutations of the INI1 tumor-suppressor gene on chromosome band 22q11.2. We have recently developed an INI1 immunohistochemical staining assay. Negative staining of tumor cells resulting from inactivation of the INI1 gene is a consistent feature of AT/RT. Mutations of INI1 in some CPCs have been reported. The purpose of the present study was to determine if immunohistochemical staining with an INI1 antibody would provide a sensitive means of distinguishing between CPC and AT/RT. We examined 28 tumors with a submitted diagnosis of CPC. Twenty-one CPCs showed retained expression of INI1 and seven tumors showed loss of INI1 expression. Cytogenetic, FISH, and/or INI1 mutation results were also available for 13 tumors. In three of the seven cases, monosomy 22 was the only cytogenetic abnormality, suggestive of AT/RT. However, monosomy 22 was also identified in 3 tumors with complex karyotypes that retained INI1 expression. The 7 tumors that were immunonegative for INI1 had features that were consistent with AT/RT. Immunostaining for INI1 protein is retained in the majority of CPC and is lost in AT/RT. This expression pattern seems to better define the 2 groups of tumors than does light or electron microscopy, routine immunohistochemistry, or cytogenetic analysis alone.

Adolescent↗
PubMed2005

Monomorphous angiocentric glioma: a distinctive epileptogenic neoplasm with features of infiltrating astrocytoma and ependymoma.

We present 8 examples of a neoplasm with features of both astrocytoma and ependymoma that may represent a distinct clinicopathologic entity. The cerebral hemispheric tumors occurred in patients that were 3, 4, 12, 14, 15, 26, 30, and 37 years of age. All presented with seizures that, with the exception of 2, began in childhood. Magnetic resonance imaging studies showed ill-defined, T2-hyperintense, generally noncontrast-enhancing lesions that, although centered on the cortex or amygdala, extended into the underlying white matter for a short distance. Histologically, the variably infiltrative tumors were distinctively angiocentric with well-developed perivascular pseudorosettes in some cases. Longitudinal and/or circumferential orientations of perivascular cells were common also. The cells were uniform in their cytologic features from case to case and were bipolar in all but one case. A glial nature was inferred from immunoreactivity for GFAP, and ependymal differentiation was suggested by positivity for EMA in three cases and ultrastructural features in one. Overall, the tumors were biologically indolent except for one that recurred and ultimately proved fatal.

Adolescent↗
PubMed2004

Dose-dependent effects of platelet-derived growth factor-B on glial tumorigenesis.

Platelet-derived growth factor (PDGF) is expressed in many different tumors, but its precise roles in tumorigenesis remain to be fully defined. Here, we report on a mouse model that demonstrates dose-dependent effects of PDGF-B on glial tumorigenesis. By removing inhibitory regulatory elements in the PDGFB mRNA, we are able to substantially elevate its expression in tumor cells using a retroviral delivery system. This elevation in PDGF-B production results in tumors with shortened latency, increased cellularity, regions of necrosis, and general high-grade character. In addition, elevated PDGF-B in these tumors also mediates vascular smooth muscle cell recruitment that supports tumor angiogenesis. PDGF receptor (PDGFR) signaling appears to be required for the maintenance of these high-grade characteristics, because treatment of high-grade tumors with a small molecule inhibitor of PDGFR results in reversion to a lower grade tumor histology. Our data show that PDGFR signaling quantitatively regulates tumor grade and is required to sustain high-grade oligodendrogliomas.

5' Untranslated Regions↗
PubMed2004

Thiotepa-based high-dose chemotherapy with autologous stem-cell rescue in patients with recurrent or progressive CNS germ cell tumors.

PURPOSE: To evaluate the efficacy and toxicity of high-dose chemotherapy (HDC) followed by autologous stem-cell rescue (ASCR) in patients with relapsed or progressive CNS germ cell tumors (GCTs). PATIENTS AND METHODS: Twenty-one patients with CNS GCTs who experienced relapse or progression despite having received initial chemotherapy and/or radiotherapy were treated with thiotepa-based HDC regimens followed by ASCR. RESULTS: Estimated overall survival (OS) and event-free survival (EFS) rates for the entire group 4 years after HDC were 57% +/- 12% and 52% +/- 14%, respectively. Seven of nine (78%) patients with germinoma survived disease-free after HDC with a median survival of 48 months. One patient died as a result of progressive disease (PD) 39 months after HDC, and another died as a result of pulmonary fibrosis unrelated to HDC 78 months after ASCR without assessable disease. However, only four of 12 patients (33%) with nongerminomatous germ cell tumors (NGGCTs) survived without evidence of disease, with a median survival of 35 months. Eight patients with NGGCTs died as a result of PD, with a median survival of 4 months after HDC (range, 2 to 17 months). Patients with germinoma fared better than those with NGGCTs (P =.016 and.014 for OS and EFS, respectively). Patients with complete response to HDC also had significantly better outcome (P <.001 for OS and EFS) compared with patients with only a partial response or stable disease. There were no toxic deaths because of HDC. CONCLUSION: Dose escalation of chemotherapy followed by ASCR is effective therapy for patients with recurrent CNS germinomas and might be effective in patients with recurrent NGGCTs with a low tumor burden.

Adolescent↗
PubMed2004

Treatment-induced leukoencephalopathy in primary CNS lymphoma: a clinical and autopsy study.

BACKGROUND: Treatment-related leukoencephalopathy is the leading toxicity after successful treatment of primary CNS lymphoma (PCNSL). Its mechanism is poorly understood and there are no autopsy data available on such patients. METHODS: From a database of immunocompetent patients with PCNSL diagnosed between 1985 and 2001, the authors identified five autopsied patients who died of leukoencephalopathy. The authors reviewed their clinical records, MRI, and autopsy findings. RESULTS: The median age was 74 years (range 41 to 79) at PCNSL diagnosis. Symptoms of neurotoxicity developed a median of 1 month after treatment completion, and median survival was 30 months (range 22 to 68 months) after neurotoxicity onset. All had white matter hyperintensity on T2-weighted MRI, and two developed enhancing lesions 5 and 14 months following completion of treatment. At autopsy no PCNSL was identified. Myelin and axonal loss, gliosis, pallor, spongiosis, and rarefaction of the white matter were found in all; two patients had tissue necrosis that correlated with the enhancement on MRI, and one had fibrinoid necrosis of vessels. Four of the five patients had atherosclerosis of large cerebral vessels in the circle of Willis and all had small vessel disease; two had recent strokes at autopsy. CONCLUSIONS: Treatment-induced leukoencephalopathy is not a late delayed consequence of neurotoxic treatment but can be seen very early in some patients. Vascular disease may be a component of this white matter injury.

Adult↗
PubMed2003

Nemaline myopathy: a possible late complication of Hodgkin's disease therapy.

Patients who have undergone "mantle" field irradiation for Hodgkin's disease may develop symptomatic muscle atrophy in the treatment portal. This complication has received only scant attention in the clinical literature and its pathologic substrate has not been elucidated. We report the finding of nemaline myopathy in the previously irradiated and atrophic trapezius muscle of such a patient. Biopsy of clinically uninvolved gracilis muscle outside of the radiation portal revealed normal histology and ultrastructure. We are unaware of previous reports documenting such a phenomenon, which suggests that nemaline myopathy may evolve as a radiation-related disorder.

Adult↗
PubMed2003

Chordoid glioma: report of a case with unusual histologic features, ultrastructural study and review of the literature.

Chordoid gliomas are an uncommon primary brain tumor with histologic features of a chordoma and immunolabeling for glial fibrillary acid protein. We report the 32nd case with a review of the literature. The clinical, radiographic and pathologic features of the tumor are presented with new pathologic findings adding support that this lesion may be of ependymal origin. Treatment and long term outcome are limited but chordoid gliomas appear to be indolent lesions that may be cured with gross total resection.

Brain Neoplasms↗
PubMed2003

Primary leptomeningeal primitive neuroectodermal tumor.

Leptomeningeal metastases are a common complication of medulloblastomas and other primitive neuroectodermal tumors (PNETs). Much rarer are PNETs apparently arising in the leptomeninges. An 8-year-old boy presented with headache and vomiting, due to neoplastic meningitis from primary neuroectodermal tumor without an identifying mass. After craniospinal irradiation and chemotherapy (carboplatin, vincristine, cyclophosphamide and lomustine) the boy was in remission for 14 months, then suffered several relapses despite various chemotherapy regimens. After the initial presentation of 3.5 years the boy began to suffer from prolonged refractory non-convulsive status epilepticus and later expired from progression of primary leptomeningeal PNET.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

Leptomeningeal metastases from recurrent squamous cell cancer of the skin.

We report two patients with leptomeningeal metastases from squamous cell cancer of the skin. In one patient cauda equina metastases appeared 6 years after initial presentation; the tumor from radical neck dissection demonstrated perineural invasion suggesting a possible route for subarachnoid dissemination. The other patient presented 2 years after initial diagnosis with confusion and cranial nerve seven and twelve palsies. Both patients died from complications of leptomeningeal metastases.

Aged↗
PubMed2003

Solitary fibrous tumors in the central nervous system. A clinicopathologic review of 18 cases and comparison to meningeal hemangiopericytomas.

CONTEXT: Solitary fibrous tumors (SFTs) of the central nervous system are rare neoplasms that usually present as dura-based masses and clinically resemble meningiomas. Histologically, they can be similar to fibrous meningioma or hemangiopericytoma (HPC). In particular, densely cellular regions seen in some SFTs can be indistinguishable from HPC. Little is known about the biological behavior of SFTs, although most seem amenable to total resection. OBJECTIVES: To define the clinicopathologic spectrum of SFTs in the central nervous system and to outline their differences from HPC and meningioma. DESIGN: We present the clinicopathologic features of 18 patients with SFT and compare them with those of an age- and sex-matched cohort of HPCs. RESULTS: Eleven SFTs were supratentorial, 3 were infratentorial, and 4 were intraspinal. Four of the 18 tumors were intra-axial (2 in the lateral ventricles and 2 within the spinal cord). Histologically, SFTs were similar to their soft tissue counterparts. Six tumors (6/18) had densely cellular regions, and 1 tumor showed frankly anaplastic features. All but 3 patients underwent gross total resection, and there were no metastases or tumor-related mortalities during the median follow-up of 40 months. In contrast, there were 15 local recurrences (83%), 5 extracranial metastases (27%), and 4 tumor-related deaths (22%) in the HPC cohort. CONCLUSIONS: Our study presents the clinicopathologic features of SFT as a distinct entity from both meningioma and HPC. We also present unusual examples of anaplastic, intraventricular, and intramedullary spinal SFTs that expand the clinicopathologic spectrum of these uncommon and sometimes diagnostically difficult neoplasms.

Adolescent↗
PubMed2002

Primary CNS lymphoma: a whole-brain disease?

BACKGROUND: Autopsy studies reveal that most primary CNS lymphomas (PCNSL) extensively infiltrate the brain. To date, there has been no correlation of autopsy findings with a modern neuroimaging assessment of tumor burden. OBJECTIVE: To correlate autopsy findings in PCNSL to MRI findings. METHOD: From the authors' database of immunocompetent patients with PCNSL diagnosed between 1985 and 2001, 10 patients who died and had PCNSL at autopsy were identified. Their pathology was compared to MR scans obtained shortly before death. RESULTS: The median patient age was 60 years (range 44 to 80 years). There were six men and four women. Scans were performed within 4 weeks of death in seven patients, within 3 months in two patients, and within 4 months in one. Seven had enhancing lesions consistent with recurrence, and two of the three had focal T2 abnormalities. All had periventricular white matter abnormalities on T2 MR images. At autopsy, all 10 patients had widespread lymphoma throughout the CNS, but no tumor was found systemically. All had tumor infiltration in CNS regions that were normal radiographically, including T2 sequences. CONCLUSIONS: MRI underestimates the tumor burden of PCNSL. Bulky disease is seen as a contrast-enhancing lesion because of disruption of the blood-brain barrier, but microscopic tumor infiltration may lead to T2 hyperintensity or be completely normal radiographically.

Adult↗
PubMed2002

Ink4a-Arf loss cooperates with KRas activation in astrocytes and neural progenitors to generate glioblastomas of various morphologies depending on activated Akt.

Deletion of the INK4a-ARF locus is found in the majority of human malignant gliomas. However, the role of INK4a-ARF loss in gliomagenesis is unclear. Animal modeling has shown that mice with targeted deletions in the Ink4a-Arf gene do not develop spontaneous gliomas. We have previously reported that combined KRas and Akt signaling could induce glioblastoma (GBM) formation from neural progenitor cells but had no effect in differentiated astrocytes. In this investigation, we have studied the effects of Ink4a-Arf loss on the formation of GBM induced by KRas and Akt gene transfer into neural progenitor cells and astrocytes. We show here that Ink4a-Arf deficiency allows for GBM formation from astrocytes and that it enhances tumor incidence in neural progenitor cells. Furthermore, KRas alone can cooperate with deletion of the Ink4a-Arf locus in tumor formation from both neural progenitor cells and astrocytes. The resulting tumors were nestin positive and resembled a spectrum of glioma morphologies ranging in astrocytic character depending on cell-of-origin and presence of activated Akt. Our data strongly supports the view that one role of loss of Ink4a-Arf in gliomagenesis could be to sensitize astrocytes to transformation through dedifferentiation in response to the appropriate oncogenic stimuli.

Animals↗