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Kenneth D Aldape

Publications and source records attributed to Kenneth D Aldape.

29 records · Page 2Linked to original sources
PubMed2004

Cowden disease with Lhermitte-Duclos disease: case report.

BACKGROUND: We report a case and review the recent literature describing 36 patients with both Lhermitte-Duclos disease (LDD) and Cowden disease (CD). Lhermitte-Duclos disease, or dysplastic gangliocytoma, is a benign hamartomatous condition involving the cerebellum. The presenting symptoms are usually headaches, gait ataxia, and symptoms of lower cranial nerve involvement. Cowden disease is a rare autosomal dominant disease that usually presents with multiple mucocutaneous lesions. Patients with CD are prone to multiple systemic malignancies, the most common of which is breast cancer. Recent studies have demonstrated an association between LDD and CD. METHODS: A 44-year-old woman with a previous history of breast cancer, multiple benign skin lesions, Hashimoto's thyroiditis, and chronic headaches presented with exacerbation of her headaches during the previous year. Magnetic resonance imaging of the brain revealed a right cerebellar nonenhancing mass and an acquired tonsillar herniation. RESULTS: The patient underwent resection of the right cerebellar mass, posterior fossa decompression, C1 and C2 laminectomies, and a duraplasty. Pathologic examination confirmed LDD. The patient recovered well after surgery, with immediate improvement of her headaches. CONCLUSIONS: The association between LDD and CD has been under-recognized and under-reported. Recognition of this association has direct clinical relevance, because diligent monitoring of individuals with LDD and CD may lead to the early detection of systemic malignancies.

Adult↗
PubMed2004

Immunohistochemical detection of EGFRvIII in high malignancy grade astrocytomas and evaluation of prognostic significance.

The purpose of this study was to establish an accurate and accessible immunohistochemical (IHC) method for detecting vIII Egf receptor and to assess the prognostic significance of the method as applied to the detection of vIII in malignant astrocytomas. The accuracy of the method was determined by comparing vIII immunoreactivity in formalin-fixed and paraffin-embedded tumor sections versus RT-PCR results from the analysis of RNA extracted from corresponding frozen specimens. RT-PCR revealed vIII transcript in 18 of 44 cases in this series, and IHC analysis of matched formalin-fixed and paraffin-embedded sections showed EGFRvIII reactivity in each of these 18 tumors, as well as 1 additional tumor that was negative for vIII transcript. EGFR amplification was evident in all tumors expressing vIII; none of the 15 tumors lacking amplified EGFR were positive for vIII transcript or vIII protein. IHC analysis for vill expression was next applied to a large series of anaplastic astrocytomas (AAs) and glioblastoma multiforme (GBMs) from clinical trial patients with complete follow-up and that had been previously examined by FISH for amplified EGFR. Among the GBMs, vIII detection by IHC was determined in 19 of 46 cases (41.3%) with EGFR amplification, and in only 3 of 59 tumors lacking amplified EGFR (5.1%). Among the AAs, vIII expression was observed in 3 of 14 cases with amplified EGFR (21.4%) and in 6 of 49 cases without EGFR amplification (12.2%). GBM and AA patient survival analysis as a function of vIII expression showed contrasting results, with vIII positivity having no association with survival among GBM patients (p = 0.84), but being highly associated with reduced survival among AA patients (p = 0.0016). This latter finding, though quite possibly a result of vIII's association with increasing AA patient age, suggests that vIII IHC will be useful for identifying and/or confirming the identity of malignant astrocytomas whose clinical behavior is consistent with that of GBM.

Adult↗
PubMed2004

The mitosis-specific antibody anti-phosphohistone-H3 (PHH3) facilitates rapid reliable grading of meningiomas according to WHO 2000 criteria.

Mitotic figure (MF) counting is the most objective criterion for grading of meningiomas according to the 2000 World Health Organization (WHO) classification. However, the search for the area(s) of highest mitotic activity is tedious, and there is high interobserver variability in differentiating MF from apoptotic cells. We tested the utility of the mitosis-specific marker phosphohistone-H3 (PHH3) to enhance rapid recognition of MFs and quick reliable grading of meningioma. Fifty-four archival meningiomas (26 benign, 20 atypical, 8 anaplastic) were reclassified according to current WHO criteria. PHH3-immunostained MFs were counted the same way as in hematoxylin and eosin-stained sections. Anti-PHH3-labeled MFs were easily seen and permitted quick identification of the area(s) of highest mitotic activity. Count results (mean) show a strong correlation between both methods: benign, hematoxylin and eosin 1.4, PHH3 2.2; atypical, hematoxylin and eosin 9.0, PHH3 15.9; anaplastic, hematoxylin and eosin 22.4, PHH3 34.1. PHH3 counting yielded greater sensitivity and in 12 cases (22.2%) suggested a change in grade (increased 9; lowered 3). All cases in which PHH3 lowered the grade were from older blocks, suggesting a loss of antigen preservation. PHH3 immunostaining facilitates the rapid reliable grading of meningiomas by focusing attention on the most mitotically active areas and by allowing easy and objective differentiation of MFs from apoptotic nuclei.

Adolescent↗
PubMed2004

Intramedullary and extramedullary solitary fibrous tumor of the cervical spine. Case report and review of the literature.

Solitary fibrous tumor is a spindle cell tumor deriving from mesenchymal cells that arises most commonly in the pleura. Only very recently has this tumor been reported in the spine. A solitary fibrous tumor strongly resembles other spindle cell neoplasms of the spine and may be an unrecognized entity if not routinely considered in the differential diagnosis of spinal neoplasms. The authors report an unusual intra- and extramedullary location for a solitary fibrous tumor of the cervical spine. Findings in this case and a comprehensive review of the literature indicate that solitary fibrous tumors can originate from various spinal anatomical substrates and mimic both intra- and extramedullary tumor types.

Cervical Vertebrae↗
PubMed2003

A model of molecular interactions on short oligonucleotide microarrays.

High-density short oligonucleotide microarrays have become a widely used tool for measuring gene expression on a large scale. However, details of the mechanism of binding on microarrays remain unclear. Short oligonucleotide probes currently synthesized on microarrays are often ineffective as a result of limited sequence specificity or low sensitivity. Here, we describe a model of binding interactions on microarrays that reveals how probe signals depend on probe sequences and why certain probes are ineffective. The model indicates that the amount of nonspecific binding can be estimated from a simple rule. Using this model, we have developed an improved measure of gene expression for use in data analysis.

Binding Sites↗
PubMed2003

Grade II astrocytomas are subgrouped by chromosome aberrations.

Grade II astrocytoma is defined as a low-grade tumor, yet patients have a wide range of survival and tumors can quickly progress to high-grade astrocytoma/glioblastoma. Previous studies using comparative genomic hybridization (CGH) failed to demonstrate frequent copy number aberrations (CNA) in these tumors. This may be related to technical difficulties because infiltrating astrocytic tumors are often intermixed with normal brain tissue. We developed methods to exclude most normal tissue and use small amounts of DNA for CGH by microdissecting small regions of tumor from paraffin sections and amplifying extracted DNA using degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR). Using this method, we examined 30 grade II astrocytoma cases. We found CNA in 25 cases (83%), with a mean of two CNA per case. The most frequent CNA were gains on 7q (12 cases), 5p (5 cases), 9 (5 cases), and 19p (3 cases), and losses on 19q (7 cases), 1p (6 cases), and Xp (3 cases). Gain on 7q and losses on 1p/19q were mutually exclusive. This is the first report on the genetic characterization of low-grade astrocytomas using CGH from microdissected and formalin-fixed tissue. The comparatively large number of cases in this study allows us to suggest that these tumors are genetically subgrouped.

Adolescent↗
PubMed2003

CC chemokine receptor 8 in the central nervous system is associated with phagocytic macrophages.

CC chemokine receptor 8 (CCR8) has been detected in vitro on type 2 helper and regulatory lymphocytes, which might exert beneficial functions in multiple sclerosis (MS) and on macrophages and microglia, possibly promoting tissue injury in MS lesions. To discriminate the relevant expression pattern in vivo, we defined the cell types that expressed CCR8 in MS lesions and determined the relationship of CCR8 expression and demyelinating activity. CCR8 was not expressed on T cells but was associated with phagocytic macrophages and activated microglia in MS lesions and directly correlated with demyelinating activity. To identify factors associated with CCR8 expression, the study was extended to other central nervous system (CNS) pathologies. CCR8 was consistently expressed on phagocytic macrophages and activated microglia in stroke and progressive multifocal leukoencephalopathy, but not expressed on microglia in pathologies that lacked phagocytic macrophages such as senile change of the Alzheimer's type. CCR8 was up-regulated by macrophage differentiation and activating stimuli in vitro. In summary CNS CCR8 expression was associated with phagocytic macrophages and activated microglial cells in human CNS diseases, suggesting that CCR8 may be a feasible target for therapeutic intervention in MS. CCR8 expression may also indicate a selective program of mononuclear phagocyte gene expression.

Adult↗
PubMed2003

Sarcomatous change after sellar irradiation in a growth hormone-secreting pituitary adenoma.

BACKGROUND: Although the benefits of radiotherapy for pituitary adenomas are well-documented, post-irradiation sarcomas of the sella are rarely seen, with only 20 cases (mainly of fibrosarcoma) reported in the medical literature. METHOD: We describe a case of post-irradiation sarcoma five years after surgery followed by external-beam irradiation for an extensive and locally invasive growth hormone-secreting tumor. The patient was subsequently given pegvisomant, an antagonist of growth hormone receptor, to control symptoms of growth hormone excess. RESULTS: The patient underwent transsphenoidal resection of the recurrent tumor, followed by adjuvant chemotherapy. This led to significant relief in the patient's symptoms including radiological evidence of tumor shrinkage, but the tumor regrew when, owing to dose-limiting toxicity, chemotherapy was stopped. CONCLUSIONS: Post-irradiation sarcomas of the pituitary are well-recognized but rare. They should be suspected in patients following sellar irradiation who show abrupt onset of new symptoms and appropriate radiological findings, and such tumors may respond to cytotoxic chemotherapy.

Adenoma↗
PubMed2003

The prognostic value of neurologic function in astrocytic spinal cord glioma.

To assess the prognostic value of neurologic function (NF) in patients with astrocytic spinal cord glioma, we conducted a retrospective study of 25 patients who were treated at our institution between January 1970 and December 1999. The median age was 40 years, and the median follow-up was 54 months. Nineteen patients had a biopsy, 5 had a subtotal resection, and 1 had a gross total resection. Twenty-two patients received postoperative radiotherapy to a median dose of 45 Gy. NF ratings of 1 and 2 were considered favorable, and 3 and 4 were considered unfavorable, based on a scale of 1 to 4. Dual neuropathologic review confirmed the tumor to be low, intermediate, or high grade, based on the WHO grades I-II, III, or IV, respectively. Actuarial rates of local control (LC), progression-free survival (PFS), and overall survival (OS) were analyzed. Our study results revealed that an improved 5-year OS rate was associated with favorable NF at diagnosis (73% vs. 22% for patients with unfavorable NF; P = 0.04) and favorable NF before radiation therapy (89% vs. 28% for patients with unfavorable NF; P = 0.049). There was a significant difference in OS based on tumor grade ( P < 0.001) and age (risk ratio, 1.04; P = 0.027). PFS and LC were significantly better for young patients and those with lower tumor grade ( P < 0.05). A multivariate analysis of age, NF at diagnosis, and postoperative NF for all patients showed postoperative NF and age to be independent prognostic factors for OS. We conclude that favorable NF may be associated with improved outcome in patients with astrocytic spinal cord glioma.

Adolescent↗
PubMedDate not supplied

Molecular epidemiology of glioblastoma.

Glioblastoma (GBM) is the most important primary brain tumor, both in terms of its incidence and its devastating impact on the unfortunate patients who have it. Although several well-defined hereditary syndromes predispose to malignant gliomas, most cases occur in the absence of a such a syndrome. The role of environmental factors, based on the known associations to date, also appears limited when compared with the total number of patients affected. It is clear that much remains to be discovered to better elucidate the causes of GBM, but the increasing recognition of molecular subtypes may help advance this field. This review highlights current insights into the molecular epidemiology of GBM.

Brain Neoplasms↗