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2.
Curr Oncol ; 18(3): e158-62, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21655154

RESUMEN

Rosai-Dorfman disease is a rare lymphoproliferative disorder that can have nodal and extranodal manifestations. In the absence of established guidelines for the management of this condition, various therapeutic modalities are used, including radiotherapy. Radiation dosages and fractionation schedules have not been reported in all instances. We present a case in which glottic and subglottic Rosai-Dorfman lesions causing airway obstruction in a frail steroid-refractory patient were put into complete remission using radiotherapy. The lesions responded transiently to a course of prednisone, but responded completely to external-beam radiation, with minimal side effects to the patient.

3.
J Digit Imaging ; 24(3): 411-23, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20532587

RESUMEN

In this paper, a new neural-fuzzy approach is proposed for automated region segmentation in transrectal ultrasound images of the prostate. The goal of region segmentation is to identify suspicious regions in the prostate in order to provide decision support for the diagnosis of prostate cancer. The new automated region segmentation system uses expert knowledge as well as both textural and spatial features in the image to accomplish the segmentation. The textural information is extracted by two recurrent random pulsed neural networks trained by two sets of data (a suspicious tissues' data set and a normal tissues' data set). Spatial information is captured by the atlas-based reference approach and is represented as fuzzy membership functions. The textural and spatial features are synthesized by a fuzzy inference system, which provides a binary classification of the region to be evaluated.


Asunto(s)
Lógica Difusa , Procesamiento de Imagen Asistido por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Algoritmos , Humanos , Masculino , Próstata/diagnóstico por imagen , Curva ROC , Sensibilidad y Especificidad , Ultrasonografía
4.
Phys Med Biol ; 50(15): N175-85, 2005 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-16030375

RESUMEN

This note focuses on extracting and analysing prostate texture features from trans-rectal ultrasound (TRUS) images for tissue characterization. One of the principal contributions of this investigation is the use of the information of the images' frequency domain features and spatial domain features to attain a more accurate diagnosis. Each image is divided into regions of interest (ROIs) by the Gabor multi-resolution analysis, a crucial stage, in which segmentation is achieved according to the frequency response of the image pixels. The pixels with a similar response to the same filter are grouped to form one ROI. Next, from each ROI two different statistical feature sets are constructed; the first set includes four grey level dependence matrix (GLDM) features and the second set consists of five grey level difference vector (GLDV) features. These constructed feature sets are then ranked by the mutual information feature selection (MIFS) algorithm. Here, the features that provide the maximum mutual information of each feature and class (cancerous and non-cancerous) and the minimum mutual information of the selected features are chosen, yielding a reduced feature subset. The two constructed feature sets, GLDM and GLDV, as well as the reduced feature subset, are examined in terms of three different classifiers: the condensed k-nearest neighbour (CNN), the decision tree (DT) and the support vector machine (SVM). The accuracy classification results range from 87.5% to 93.75%, where the performance of the SVM and that of the DT are significantly better than the performance of the CNN.


Asunto(s)
Algoritmos , Inteligencia Artificial , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Humanos , Imagenología Tridimensional/métodos , Almacenamiento y Recuperación de la Información/métodos , Masculino , Recto/diagnóstico por imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ultrasonografía
5.
Liver Transpl ; 6(5): 570-4, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10980055

RESUMEN

Posttransplant lymphoproliferative disease (PTLD) is associated with immunosuppression and lymphotrophic viral infections. Hepatitis C virus (HCV) has been identified as a risk factor for non-Hodgkin's lymphoma, but no association between HCV and PTLD has been shown. To investigate this possibility, we identified patients with HCV who received their first orthotopic liver transplant at our unit between January 1, 1992, and December 31, 1996, and compared them with contemporary liver transplant recipients without HCV for incidence and risk factors for PTLD and survival. Fifty-seven patients with HCV and 127 patients without HCV were compared. There was no age difference (52 v 53 years; P =.85), but there were more men in the HCV group (man-woman ratio, 2.1:1 v 0.9:1; P =.006). No difference was observed in the follow-up period, graft survival, rejection episodes, or use of different immunosuppressive regimes (P >.05 for all). Four patients with HCV (7%) developed PTLD compared with 1 patient without HCV (0.8%; P =.02). The relative odds for developing PTLD in patients with HCV were 9.5. All patients who developed PTLD were administered OKT3 induction therapy. These data suggest that PTLD may be more prevalent in patients undergoing liver transplantation for HCV-related liver disease who also receive OKT3, and that HCV infection may be a risk factor for developing PTLD.


Asunto(s)
Hepatitis C/complicaciones , Trasplante de Hígado , Trastornos Linfoproliferativos/etiología , Complicaciones Posoperatorias/etiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Inmunosupresores/uso terapéutico , Incidencia , Hepatopatías/cirugía , Hepatopatías/virología , Trastornos Linfoproliferativos/epidemiología , Masculino , Persona de Mediana Edad , Muromonab-CD3/uso terapéutico , Factores de Riesgo
6.
Cancer Genet Cytogenet ; 118(1): 35-41, 2000 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-10731588

RESUMEN

Jumping translocation is a rare cytogenetic aberration in leukemia and lymphoma, and its etiologic mechanisms are not clearly known. We report two cases with jumping translocations. One had follicular lymphoma and jumping translocations of 1q onto the telomeric regions of 5p, 9p, and 15q in three cell lines, co-existing with the specific translocation t(14;18)(q32;q21). The second case had acute myeloid leukemia (AML) and jumping translocations of 11q as the sole aberration, onto multiple derivative chromosomes in each of the abnormal cells. A total of 17 telomeric regions were seen as the recipients of 11q in this case, and 9q was always involved as one of the recipients in all abnormal cells. Fluorescence in situ hybridization (FISH) confirmed the identification of 11q material in the derivative chromosomes. While 1q has been the most common donor of acquired jumping translocations, this is the first report on jumping translocations of 11q. Different from all previously reported jumping translocations which involve only one recipient in each cell line and lead to a mosaic trisomy, multiple recipients in most of the abnormal cells in this case had led to a tetrasomy, or a pentasomy of 11q. The pattern of chromosome involvement as the recipients of 11q appears to show a continuing evolutionary process of jumping, stabilization, and spreading of the donor material into other chromosomes. Somatic recombinations between the interstitial telomeric or subtelomeric sequences of a derivative chromosome and the telomeric sequences of normal chromosomes are believed to be the underlying mechanism of jumping translocations and their clonal evolution.


Asunto(s)
Cromosomas Humanos Par 11/genética , Cromosomas Humanos Par 1/genética , Leucemia Mieloide/genética , Linfoma Folicular/genética , Translocación Genética/genética , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Aneuploidia , Pintura Cromosómica , Femenino , Humanos , Cariotipificación , Masculino , Telómero/genética
8.
Cancer Genet Cytogenet ; 115(1): 28-31, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10565296

RESUMEN

An interstitial deletion in the long arm of chromosome 8 as the sole structural anomaly was detected in a primary gastric diffuse large B-cell lymphoma, high-grade mucosa-associated lymphoid tissue (MALT) type, from a 74-year-old man. Low-grade MALT lymphoma was not seen in the sections submitted for examination. Helicobactor pylori organisms were found in a biopsy performed prior to resection of the tumor. The karyotype was described as 45, X,-Y,del(8)(q13q22). No rearrangement between chromosome 8 and others was detected with fluorescence in situ hybridization using a whole chromosome 8 painting probe. Fluorescence in situ hybridization with the C-MYC gene showed its normal location at 8q24 on both chromosomes 8 without rearrangement. Amplification of C-MYC was not detected in interphase cells. Deletion of 8q may represent a unique genomic alteration in this particular subtype of primary gastric lymphoma.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 8 , Linfoma de Células B/genética , Neoplasias Gástricas/genética , Anciano , Humanos , Inmunofenotipificación , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Metafase
9.
Leuk Res ; 23(11): 1001-6, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10576504

RESUMEN

A new complex variant Philadelphia chromosome was detected in a 65-year-old man with acute, pre-B, lymphoblastic leukemia (ALL). The classic cytogenetic analysis identified an apparently balanced three-way translocation t(1;9;22)(q25;q34;q11.2). Fluorescence in situ hybridization (FISH) studies confirmed the translocation and showed bcr/abl fusion on the der(22). However, these studies revealed that the distal part of the bcr gene was not translocated onto chromosome 1 at 1q25, but inserted into chromosome 17 at 17p12-13. This complex variant translocation was described as a t(1;9;22)(q25;q34;q11.2)ins(17;22)(p12-13;q11.2q11.2). Secondary changes including +8, an inversion of the derivative chromosome 9, a translocation t(14;20)(q11;q13), and an additional derivative 22 were also identified in most of the abnormal cells. The patient died from systemic fungemia and multiorgan failure 9 months after the diagnosis of ALL. The clinical significance of complex variant Philadelphia chromosomes in ALL is reviewed and discussed.


Asunto(s)
Cromosomas Humanos , Cromosoma Filadelfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocación Genética , Adulto , Anciano , Bandeo Cromosómico , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino
11.
Can J Surg ; 41(5): 404-6, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9793510

RESUMEN

Desmoid tumour is an unusual and aggressive tumour associated with a high recurrence rate. A 35-year-old man presented with recurrent debilitating left arm pain 2 years after undergoing bilateral transaxillary first rib resection for thoracic outlet syndrome. Nerve conduction studies demonstrated impairment of nerve conduction in the left arm. Magnetic resonance imaging of the brachial plexus demonstrated a mass at the apex of the left hemithorax involving the lower cord of the brachial plexus. Subsequent percutaneous needle biopsies failed to provided a definitive diagnosis. A cervicothoracic approach as described by Dartevelle was used to resect the lesion. Histologic and ultrastructural studies confirmed the diagnosis of a desmoid tumour. This report describes the atypical presentation of this unusual tumour and the application of the novel Dartevelle approach to secure its complete excision.


Asunto(s)
Plexo Braquial , Fibromatosis Agresiva/complicaciones , Neoplasias del Sistema Nervioso/complicaciones , Síndrome del Desfiladero Torácico/etiología , Adulto , Fibromatosis Agresiva/diagnóstico , Fibromatosis Agresiva/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias del Sistema Nervioso/diagnóstico , Neoplasias del Sistema Nervioso/patología , Complicaciones Posoperatorias , Recurrencia , Síndrome del Desfiladero Torácico/cirugía
12.
Mod Pathol ; 10(7): 708-15, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9237182

RESUMEN

Post-transplantation lymphoproliferative disorder (PTLD) and acute rejection are two serious complications of orthotopic liver transplantation that can have a similar histologic appearance. We undertook the present study to assess the best way to distinguish these two entities. We studied histologic features, immunophenotyping, and Epstein-Barr virus (EBV) status, as assessed by immunohistochemical stain and in situ hybridization (ISH), in three groups: Group I, 8 cases of PTLD post-orthotopic liver transplantation with liver involvement; Group II, 15 cases diagnosed with acute liver rejection (control group); and Group III, a subset of 6 biopsy specimens from 4 patients of Group I whose graft rejection was diagnosed within the 2 months preceding the diagnosis of PTLD. The mean proportion of plasma to plasmacytoid cells in most cases from Group I was more than 40%, whereas from Group II it was less than 25% (P = .0001). There was a higher number of B lymphocytes than T lymphocytes in Group I. The numbers of mitotic figures and immunoblasts were significantly different in the two groups (P < .0001 and P = .0005, respectively), being higher in the patients with PTLD. EBV immunostain was most specific for the diagnosis of PTLD (75% positive in Group I, negative in Group II). ISH for EBV-encoded RNA was positive in 87% of cases in Group I and only 6.6% of cases in Group II (P = .0005). In Group III, four of the six liver biopsy specimens had a low plasma cell count and were negative for EBV studies. The other two biopsy specimens in this group had 70 to 80% plasma cell infiltrate, in addition to positive EBV immunostain and ISH in one, for which tissue was available for study. We conclude that viral studies and assessment of the number of plasma cells and B lymphocytes can help to distinguish between acute rejection and early PTLD.


Asunto(s)
Rechazo de Injerto/patología , Trasplante de Hígado/efectos adversos , Trastornos Linfoproliferativos/patología , Adulto , Anciano , Biopsia , Femenino , Herpesvirus Humano 4/genética , Humanos , Inmunohistoquímica , Hibridación in Situ , Hígado/química , Hígado/patología , Trastornos Linfoproliferativos/etiología , Masculino , Persona de Mediana Edad , ARN Viral/análisis , Proteínas de la Matriz Viral/análisis
13.
Pathology ; 29(2): 141-6, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9213332

RESUMEN

Metallothioneins (MT) are low molecular weight, metal-binding proteins. The induction of MT synthesis by cytokines, hormones and other cytotoxic agents indicates its role in cellular proliferation and differentiation as well as in cellular defense mechanisms. Previous studies have detected expression of MT in various human tumors by immunohistochemical staining. In certain cases the presence of MT in a tumor may be associated with its resistance against radiation and chemotherapeutic agents. Immunohistochemical staining of MT using a rabbit polyclonal anti-rat liver MT antibody was carried out in eight gastric, two small bowel and one large bowel lymphomas, and in ten control gastrointestinal (gastric, colonic and small bowel) biopsies or excised bowel segments with benign lymphoid infiltrates. The primary antibody against rat liver MT readily cross-reacts with human MT. The neoplastic cells in nine of 11 malignant lymphomas showed weak to intense staining for MT, mostly in cytoplasm. In these cells a few nuclei (less than 5% of all tumor cells) were stained positively for MT. The benign lymphocytes in the gastrointestinal excised specimens and biopsies were mostly negative; four cases showed few positive cells. The giant cells were also positive for MT in a Crohn's disease case. We conclude that the presence or absence of MT in lymphocytes, detected by immunohistochemistry, may indicate the growth patterns of these cells. The distinct pattern of MT staining in malignant lymphoma in our study is suggestive of a potential use of MT staining as a discriminator between benign and malignant lymphoid tissues.


Asunto(s)
Biomarcadores/análisis , Sistema Digestivo/metabolismo , Mucosa Gástrica/metabolismo , Neoplasias Gastrointestinales/metabolismo , Linfoma/metabolismo , Metalotioneína/análisis , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad
14.
AJR Am J Roentgenol ; 167(6): 1473-6, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8956579

RESUMEN

The findings on sonographic examination of intestinal disorders in the right iliac fossa are often nonspecific. We have found the classification system just described useful because it leads to a meaningful differential diagnosis, which may be narrowed on the basis of various distinguishing features. The use of other imaging techniques, imaging-guided aspiration or biopsy, or surgical intervention may be necessary to make the exact diagnosis.


Asunto(s)
Enfermedades Intestinales/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ultrasonografía
15.
Mod Pathol ; 7(9): 925-9, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7534400

RESUMEN

Proliferative rates of 73 node-negative adenocarcinomas of breast with 5-year or greater follow-up were studied using cytokeratin staining in two-parameter DNA flow cytometry of archival specimens. Quality control data of accuracy of the measurements were determined and all analyses were compared with single-parameter results of the same specimens, using demarcated tumor areas, quadruple analyses, and computerized nonspecific staining subtraction. Mitotic rates of the same samples correlated highly significantly with the S-phase fractions and proliferative index (S + G2 + M phases), especially for the cytokeratin data. The predictive value of mitotic rates was found significant, but that of the DNA flow-cytometry-obtained indices was not, probably because of low numbers of deaths in this study. The cytokeratin method identified heteroploid tumors containing a diploid cell population not identifiable by single-parameter analysis. In conclusion, cytokeratin staining can be reliably applied to DNA flow cytometry of archival specimens giving accurate ploidy, S-phase fractions, and proliferative index data limited almost exclusively to neoplastic cell populations. This will permit large-scale retrospective studies aimed at establishing the usefulness of DNA flow cytometry for clinical decisions on therapy of surgically removed node-negative adenocarcinomas of breast.


Asunto(s)
Adenocarcinoma/patología , Neoplasias de la Mama/patología , ADN de Neoplasias/análisis , Queratinas/análisis , Adenocarcinoma/mortalidad , Análisis de Varianza , Neoplasias de la Mama/mortalidad , División Celular , Citometría de Flujo , Humanos , Estudios Retrospectivos , Análisis de Supervivencia
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