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Elias A Castilla

Publications and source records attributed to Elias A Castilla.

15 recordsLinked to original sources
PubMed2006

The impact of genotype on outcome in oligodendroglioma: validation of the loss of chromosome arm 1p as an important factor in clinical decision making.

OBJECT: Oligodendrogliomas are rare primary brain tumors. They comprise approximately 5 to 33% of all glial tumors but differ from astrocytomas by being associated with a more favorable prognosis, making their correct identification important. Allelic loss of chromosome arms 1p and 19q is found in a substantial subpopulation of tumors with an oligodendroglioma phenotype. Anaplastic oligodendrogliomas with allelic loss of 1p have been associated with chemosensitivity and a longer patient survival period. METHODS: Oligodendroglial neoplasms were studied using fluorescence in situ hybridization of formalin-fixed, paraffin-embedded tissue specimens; reference and target probe sets were used to map the telomeric regions of 1p and 19q. The results were correlated with the clinical characteristics of patients treated at our institution between 1993 and 2003. Data obtained in 96 patients were analyzed. This included 63 patients (65.6%) with World Health Organization (WHO) Grade II oligodendroglioma, 22 (23%) with Grade III oligodendroglioma, and 11 (11.4%) with mixed oligoastrocytoma. Analysis of 1p in patients with pure oligodendroglioma revealed a loss of 1p in 42 patients (49.4%). In 46 of these patients 19q was lost and in 70 (82.3%) there was concordance for combined loss or retention of both 1p and 19q (p < 0.0001). Patients with oligodendroglioma in whom a loss of 1p was present fared significantly better, and this outcome was unrelated to the treatment modality or WHO grade, compared with patients in whom 1p was intact (p < 0.05). CONCLUSIONS: To the authors' knowledge, this study includes the largest published series of WHO Grade II oligodendroglioma and 1p analysis. The results suggest that the association between long-term survival and 1p loss in oligodendroglioma is unrelated to treatment. The authors of further prospective studies may better determine the true value of the allelic loss of 1p and its implication for clinical decision making.

Adolescent↗
PubMed2004

Correlation between viral loads of cytomegalovirus in blood and bronchoalveolar lavage specimens from lung transplant recipients determined by histology and immunohistochemistry.

Cytomegalovirus (CMV) is an important pathogen in lung transplant recipients. Early detection of CMV end-organ disease should help with treatment management. We determined the CMV viral load by hybrid capture in bronchoalveolar lavage (BAL) fluid samples from patients who had undergone lung transplantation. For 39 of these samples (from 25 patients), corresponding transbronchial biopsy samples were available for CMV immunohistochemistry (IHC). The CMV IHC results were interpreted and categorized as positive or negative, and the positive results were subcategorized as typical if cells with both significant nuclear enlargement or Cowdry A-type inclusions and positive staining were present or as atypical if definitive nuclear staining was seen but significant nuclear enlargement was not. Diagnostic CMV viral inclusions were reported in the anatomic diagnosis, based on hematoxylin-eosin staining alone, for three (8%) of the biopsy samples. CMV was detected by IHC in 13 (33%) samples (5 typical, 8 atypical). The median CMV viral load in BAL samples was 0 copies/ml for BAL samples from patients with IHC-negative biopsy samples; 47,678 copies/ml for BAL samples from patients with biopsy samples with positive, atypical staining; and 1,548,827 copies/ml for BAL samples from patients with biopsy samples with positive, typical staining (P < 0.001). Compared to routine pathology of biopsy samples, the use of IHC increased the diagnostic yield of CMV. Also, the CMV viral load in BAL fluid samples increased along with immunoreactivity from negative to positive, atypical staining to positive, typical staining. The CMV viral load determined with the end-organ sample, the BAL fluid sample, was higher than the corresponding viral load determined with blood. Both IHC and determination of the CMV viral load in BAL samples may be useful for the detection of individuals at risk for the development of fulminant invasive CMV disease.

Bronchoalveolar Lavage Fluid↗
PubMed2003

Cyclooxygenase-2 in oligodendroglial neoplasms.

BACKGROUND: Although increased expression of cyclooxygenase-2 (COX-2) has been described in association with a variety of neoplasms, including tumors of astrocytic derivation, limited data are available on COX-2 expression in oligodendrogliomas. METHODS: The current study retrospectively reviewed 53 oligodendrogliomas and 7 oligodendroglioma-predominant oligoastrocytomas (mixed gliomas) for COX-2 expression and MIB-1 proliferative index (by immunohistochemistry) and for chromosome 1p status (by fluorescence in situ hybridization). RESULTS: Patients included 35 males and 25 females, with a mean age of 41 years (range, 12-73 years) at the time of surgery. Forty-four tumor specimens were classified as World Health Organization (WHO) Grade II neoplasms and 16 as WHO Grade III tumors. MIB-1 labeling indices (marker of cell proliferation) ranged from 0 to 22.3 (mean 4.5). Twenty-eight tumor specimens demonstrated allelic loss on chromosome 1p. Positive staining was observed in 17 tumor specimens with COX-2 antibody. COX-2-positive tumor specimens were also evaluated with CD68 (macrophage/microglial cell marker) by coimmunolabeling to confirm that the observed COX-2 immunostaining was not due to immunoreactive macrophages or microglial cells. COX-2 expression, lack of allelic loss at chromosome 1p, and high proliferation indices were associated with decreased survival (P = 0.002, P = 0.009, and P = 0.015, respectively). No correlation with outcome was found with patient gender, age at diagnosis, or histologic grade. CONCLUSIONS: Chromosome 1p, COX-2 immunoreactivity, and MIB-1 labeling indices correlated with outcome and were associated with decreased survival. There was not a one-to-one correspondence between COX-2 immunoreactivity and lack of allelic loss at chromosome 1p. Tumors with expression of COX-2 by immunohistochemistry may, in theory, benefit from treatment with therapeutic agents that inhibit COX-2.

Adolescent↗
PubMed2003

Initial evaluation of Cyberknife technology for extracorporeal renal tissue ablation.

OBJECTIVES: To determine whether Cyberknife technology can be applied to renal tissue safely and effectively. The goal was to achieve the high efficacy of a surgical treatment, with the low morbidity of a noninvasive intervention. METHODS: The Cyberknife is a frameless, image-guided radiosurgical device. This innovative extracorporeal treatment combines a linear accelerator mounted on a highly maneuverable robotic arm. The Cyberknife is unique in that it divides the high-dose radiation necessary to ablate the lesion completely into up to 1200 beams. Each one of these beams of radiation has a significantly reduced dose. Therefore, the individual dose of each beam is essentially benign to the pathway and surrounding tissue. However, at the focal point of these beams, the dose is additive, and the desired ablative dose is attained. Predetermined "lesions" in 16 kidneys were treated in vivo in the porcine model. Complete treatment was accomplished in one session per animal, with no complications. Gross and histologic evaluations were completed at 4, 6, or 8 weeks. RESULTS: The degree of radiation changes correlated with longer treatment intervals. After 8 weeks, the lesions showed complete fibrosis. The zones of complete fibrosis were characterized by dense, paucicellular connective tissue completely devoid of all normal kidney elements, including tubules and glomeruli. CONCLUSIONS: This initial preclinical evaluation of the Cyberknife for extracorporeal renal tissue ablation appears to be very promising and demonstrated its ability to ablate a targeted area precisely and completely with relative sparing of the surrounding tissue. This innovative technology introduces an exciting approach as a potential treatment option of renal masses in the future.

Animals↗
PubMed2003

Interobserver variability in determining MIB-1 labeling indices in oligodendrogliomas.

Several studies have shown that MIB-1 labeling indices correlate well with tumor grade and prognosis in a variety of tumor types. Several factors are responsible for some degree of variability in the determination of labeling indices. Interobserver variability is one of the factors often cited as responsible for this variability. A slide from each of 30 oligodendrogliomas, stained with MIB-1 antibody, was distributed to six pathologists. The same set of slides was reviewed by each individual. Each pathologist was instructed to determine a MIB-1 labeling index by evaluating 1,000 tumor cell nuclei from the area of the slide with the most staining. The labeling index record reflected a percentage of positive-staining tumor cells. Interobserver agreement was compared. MIB-1 labeling indices ranged from 0 to 45.7. Overall agreement was good (> or =0.75) with a concordance coefficient of 0.832 (confidence interval, 0.700 to 0.909). Variability was greater among tumors with higher labeling indices as compared with tumors with labeling indices closer to 0. The overall agreement of MIB-1 labeling indices, while not perfect, was good. The generally minor variability among observers may be related to differences in the area of the slide evaluated and in differing lower thresholds for interpreting positivity. Further improvement of concordance may theoretically be attainable by further training and discussion among observers.

Biomarkers, Tumor↗
PubMed2003

Cavitary mass lesion and recurrent pneumothoraces due to Paragonimus kellicotti infection: North American paragonimiasis.

North American paragonimiasis is well described in omnivorous and carnivorous animals on this continent. Humans are rarely infected, largely because of dietary customs, but are at risk for infection if raw or undercooked crayfish are consumed. We describe a patient with a pleuropulmonary infection due to Paragonimus kellicotti that presented as recurrent pneumothoraces and a cavitary lesion. This is the first case of North American paragonimiasis in which the diagnosis was based on the morphology of the eggs present in histologic sections.

Adult↗
PubMed2003

Immunohistochemical expression of cathepsin D in meningiomas.

We retrospectively studied the expression of cathepsin D by immunohistochemical analysis in 86 meningiomas (World Health Organization [WHO] grade I, n = 44; WHO grade II, n = 21; WHO grade III, n = 21) and correlated the results with tumor grade and outcome. Staining was scored semiquantitatively based on distribution among neoplastic cells as follows: 0, no staining; 1+, 5% or less of the cells; 2+, 6% to 20%; 3+, 21% to 50%; and 4+, more than 50% of the cells. Cathepsin D expression was observed as follows: 0, 10 cases (12%); 1+, 25 cases (29%); 2+, 15 cases (17%); 3+, 12 cases (14%); and 4+, 24 cases (28%). A higher degree of cathepsin D immunostaining was associated with low tumor grade (P = .0014), low mitotic count (P < .0001), low apoptotic count (P < .0001), and the development of recurrence (P = .035). There was no correlation with outcome or MIB-1 proliferation index. Cathepsin D expression by immunohistochemical analysis was identified in the majority (88% [76/86]) of meningiomas studied. A greater degree of immunoreactivity was observed in the WHO grade I group.

Adolescent↗
PubMed2002

Prognostic importance of resection margin width after nephron-sparing surgery for renal cell carcinoma.

OBJECTIVES: To examine the relationship between the width of the resection margin and disease progression in renal cell carcinoma (RCC) after nephron-sparing surgery (NSS). During NSS for RCC, it is standard practice to excise the tumor along with a surrounding margin of normal parenchyma (margin of resection) to ensure complete resection of the neoplasm. However, no agreement has been reached on how wide the margin of resection should be. METHODS: We retrospectively reviewed the histopathologic sections and medical records of 69 patients with localized RCC who had undergone NSS between 1976 and 1988 to determine whether the resection margin, tumor size, TNM stage, and Fuhrman nuclear grade were associated with disease progression (defined as local tumor recurrence or metastasis). The mean postoperative follow-up interval was 8.5 years. RESULTS: No association was found between the width of the resection margin and disease progression (P = 0.98, log-rank test). Both TNM stage and Fuhrman nuclear grade correlated with disease progression. Patients with T1-T2 tumors had lower progression (P <0.001, log-rank test), and increased Fuhrman nuclear grade correlated with more disease progression (P <0.001, log-rank test). CONCLUSIONS: The width of the resection margin after NSS for RCC does not correlate with long-term disease progression. A histologic tumor-free margin of resection, irrespective of the width of the margin is sufficient to achieve complete local excision of RCC.

Adult↗
PubMed2002

Cyclooxygenase-2 (COX-2) expression by immunohistochemistry in glioblastoma multiforme.

Cyclooxygenase-2 (COX-2) (an enzyme responsible for the conversion of arachidonic acid to prostaglandin) upregulation has been described in association with a variety of tumors including gliomas. This study reviews the immunohistochemical profile of 47 glioblastoma multiforme using COX-2 antibody and correlates the results with MIB-1 (marker of cell proliferation) immunostaining. Positive staining with COX-2 was observed in 35 tumors (74.5%); more than 10% tumor cell positivity was seen in 10 tumors (21.3%). Immunostaining results were as follows: no staining, N = 12 (25.5%); 0% to 5% of tumor cells, N = 20 (42.6%); 5% to 10%, N = 5 (10.6%); 10% to 20%, N = 4 (8.5%); 20% to 50%, N = 4 (8.5%); and greater than 50%, N = 2 (4.3%). The mean MIB-1 labeling index for all tumors ranged from 3.0 to 76.4 (mean, 19.6). Mean MIB-1 labeling indices were higher in tumors with greater than 5% COX-2 immunostaining (mean MIB-1 labeling index, 23.5) versus tumors with 0% to 5% COX-2 immunostaining (mean MIB-1 labeling index, 17.7). There is evidence of COX-2 expression by immunohistochemistry in the majority of glioblastoma multiforme. As a group, tumors with a higher rate of cell proliferation tended to have increased expression of COX-2. These findings are significant in that therapeutic agents, which inhibit COX-2, are currently available and may play a role in the management of glioblastoma multiforme.

Adolescent↗
PubMed2002

Adult xanthogranuloma of the vulva: case report and review.

We report a case of adult xanthogranuloma arising on the labia majora of a 48-year-old female. Although histologically similar to juvenile xanthogranuloma, the clinical presentation and natural history are unique. To our knowledge this is the first case described of this rare histiocytic lesion arising in the vulva.

Antigens, CD↗
PubMed2002

Evaluation of Chlamydia pneumoniae and Mycoplasma pneumoniae as etiologic agents of persistent cough in adolescents and adults.

Chlamydia pneumoniae and Mycoplasma pneumoniae were evaluated as agents of persistent cough in adolescents and adults (n = 491). Tests of 473 respiratory specimens by culture or PCR or both identified four episodes (0.8%) of M. pneumoniae-associated illness and no episodes of C. pneumoniae illness, suggesting that these bacteria do not frequently cause persistent cough.

Adolescent↗
PubMed2002

Brain-invasive solitary fibrous tumor of the meninges: report of a case.

Solitary fibrous tumor is a mesenchymal neoplasm that most commonly arises in the pleura, but also in multiple extrapleural sites including, rarely, the meninges. Immunohistochemical findings facilitate its differentiation from other spindle cell lesions such as fibrous meningioma. Although the great majority of extrapleural solitary fibrous tumors behave in a benign fashion, only rare examples of brain-invasive tumors have been documented. We present a case of a brain-invasive solitary fibrous tumor arising in the meninges of a 40-year-old woman. The tumor was marked by focally prominent hypercellularity, moderate nuclear pleomorphism, and increased mitotic activity. Focal infiltration into the underlying brain parenchyma was observed. The tumor was CD34 positive and EMA negative.

Adult↗
PubMed2002

Chromosome 1p allelic loss by fluorescence in situ hybridization is not observed in dysembryoplastic neuroepithelial tumors.

Differentiation of dysembryoplastic neuroepithelial tumor (DNT) from cystic low-grade oligodendroglioma, particularly in a limited biopsy orfragmented specimen, may be impossible. Research has shown that allelic loss of chromosome 1p is a relatively common finding in oligodendrogliomas. Little is known about chromosome 1p status in DNT. We retrospectively evaluated 14 DNTs for loss of heterozygosity (LOH) on chromosome 1p by fluorescence in situ hybridization (FISH) and compared the results with 1p FISH analysis in 57 low-grade oligodendrogliomas (World Health Organization grade II). The 14 DNTs arose in 8 females and 6 males (mean age, 20.9 years at the time of surgery). All 14 DNTs were 1p intact by FISH analysis. The 57 low-grade oligodendrogliomas arose in 31 males and 26 females (mean age, 43.2 years). LOH on chromosome 1p was present in 31 (54%) of 57 tumors; the remaining 26 tumors were 1p intact. LOH on chromosome 1p is not a feature of DNTs. LOH on chromosome 1p may be a useful differential diagnostic feature (favoring oligodendroglioma) in a subset of cases in which specimen fragmentation or size raises the differential diagnosis of DNT vs oligodendroglioma.

Adolescent↗