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1.
Acta Neurol Belg ; 108(1): 21-3, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18575183

RESUMEN

Limbic encephalitis (LE) is frequently associated with malignancy. Non-paraneoplastic LE is less common and in this form, voltage-gated potassium channel (VGKC) antibodies are usually found. However in 2007 the spectrum was further extended by a report on four patients with presumed non-paraneoplastic LE in whom neither VGKC-antibodies nor other antibodies could be found (Samarasekera et al. 2007). Despite immunmodulatory treatment all these patients had severe neurological residual symptoms. Here we describe a further patient in whom extensive diagnostic procedures suggested non-paraneoplastic antibody-negative limbic encephalitis. Although this woman had prolonged status epilepticus during seven weeks, her outcome was excellent.


Asunto(s)
Epilepsia del Lóbulo Temporal/etiología , Encefalitis Límbica/complicaciones , Encefalitis Límbica/diagnóstico , Estado Epiléptico/etiología , Adulto , Amnesia/etiología , Anticonvulsivantes/uso terapéutico , Autoanticuerpos/sangre , Enfermedades Autoinmunes del Sistema Nervioso/diagnóstico , Enfermedades Autoinmunes del Sistema Nervioso/inmunología , Enfermedades Autoinmunes del Sistema Nervioso/fisiopatología , Enfermedad Crónica , Diagnóstico Diferencial , Epilepsia del Lóbulo Temporal/fisiopatología , Epilepsia del Lóbulo Temporal/terapia , Femenino , Hipocampo/inmunología , Hipocampo/patología , Hipocampo/fisiopatología , Humanos , Encefalitis Límbica/fisiopatología , Encefalitis Límbica/terapia , Imagen por Resonancia Magnética , Metilprednisolona/uso terapéutico , Trastornos de la Personalidad/etiología , Plasmaféresis , Estado Epiléptico/fisiopatología , Estado Epiléptico/terapia , Resultado del Tratamiento
2.
Clin Cancer Res ; 24(9): 2116-2127, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29476017

RESUMEN

Purpose: Cancer-initiating cells (C-IC) have been described in multiple cancer types, including colorectal cancer. C-ICs are defined by their capacity to self-renew, thereby driving tumor growth. C-ICs were initially thought to be static entities; however, recent studies have determined these cells to be dynamic and influenced by microenvironmental cues such as hypoxia. If hypoxia drives the formation of C-ICs, then therapeutic targeting of hypoxia could represent a novel means to target C-ICs.Experimental Design: Patient-derived colorectal cancer xenografts were treated with evofosfamide, a hypoxia-activated prodrug (HAP), in combination with 5-fluorouracil (5-FU) or chemoradiotherapy (5-FU and radiation; CRT). Treatment groups included both concurrent and sequential dosing regimens. Effects on the colorectal cancer-initiating cell (CC-IC) fraction were assessed by serial passage in vivo limiting dilution assays. FAZA-PET imaging was utilized as a noninvasive method to assess intratumoral hypoxia.Results: Hypoxia was sufficient to drive the formation of CC-ICs and colorectal cancer cells surviving conventional therapy were more hypoxic and C-IC-like. Using a novel approach to combination therapy, we show that sequential treatment with 5-FU or CRT followed by evofosfamide not only inhibits tumor growth of xenografts compared with 5-FU or CRT alone, but also significantly decreases the CC-IC fraction. Furthermore, noninvasive FAZA-PET hypoxia imaging was predictive of a tumor's response to evofosfamide.Conclusions: Our data demonstrate a novel means to target the CC-IC fraction by adding a HAP sequentially after conventional adjuvant therapy, as well as the use of FAZA-PET as a biomarker for hypoxia to identify tumors that will benefit most from this approach. Clin Cancer Res; 24(9); 2116-27. ©2018 AACR.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Hipoxia/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Nitroimidazoles/administración & dosificación , Mostazas de Fosforamida/administración & dosificación , Profármacos/administración & dosificación , Animales , Biomarcadores , Caspasas/metabolismo , Hipoxia de la Célula/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Quimioradioterapia , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/radioterapia , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Femenino , Humanos , Masculino , Ratones , Fenotipo , Tomografía de Emisión de Positrones , Nivel de Atención , Vía de Señalización Wnt , Ensayos Antitumor por Modelo de Xenoinjerto
3.
J Clin Pathol ; 70(3): 237-243, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27681847

RESUMEN

AIM: Several regression grading systems have been proposed for neoadjuvant chemoradiation-treated pancreatic ductal adenocarcinoma (PDAC). This study aimed to examine the utility, reproducibility and level of concordance of three most frequently used grading systems. METHODS: Four gastrointestinal pathologists used the College of American Pathologists (CAP), Evans, MD Anderson Cancer Centre (MDA) regression grading systems to grade 14 selected cases (7-20 slides from each case) of neoadjuvant chemoradiation-treated PDAC. A postscoring discussion with each pathologist was conducted. The results were entered into a standardised data collection form and statistical analyses were performed. RESULTS: There was little concordance across the three systems. The Kendall coefficient of concordance agreement scores were: CAP: 2-poor, 2-fair; Evans: 1-fair, 1-moderate, 2-good; MDA: 1-poor, 2-moderate, 1-good. Interpretation in all three grades in the CAP grading system was a source of discrepancy. Furthermore, using fibrosis as a criterion to assess regression was contentious. In the Evans system, quantifying tumour destruction using arbitrary percentage cut-offs (ie, 9% vs 10%; 50% vs 51%, etc) was imprecise and subjective. Although the MDA system generated greatest concordance, this was due to 'oversimplification' surrounding wide, arbitrarily assigned thresholds of 5% of tumour. CONCLUSIONS: All systems lacked precision and clarity for accurate regression grading. Presently the clinical utility and impact of histological regression grading in patient management is questionable. There is a need to re-evaluate regression grading in the pancreas and establish a reproducible, clinically relevant grading system.


Asunto(s)
Carcinoma Ductal Pancreático/patología , Clasificación del Tumor/métodos , Neoplasias Pancreáticas/patología , Anciano , Carcinoma Ductal Pancreático/terapia , Quimioradioterapia Adyuvante , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Clasificación del Tumor/normas , Variaciones Dependientes del Observador , Neoplasias Pancreáticas/terapia
4.
Pathology ; 49(4): 391-396, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28438394

RESUMEN

This study aimed to ascertain views, incidence of reporting and diagnostic criteria for gastric foveolar dysplasia. A questionnaire, a post-questionnaire discussion and microscopic assessment of selected cases was conducted by gastrointestinal pathologists to explore the above-stated aims. Fifty-four percent of respondents never or rarely diagnosed gastric foveolar-type dysplasia. The general consensus was that round nuclei, lack of nuclear stratification, presence of inflammation/damage and surface maturation favoured reactive change; while architectural abnormalities/complexity and nuclear enlargement mainly were used to separate low-grade from high-grade foveolar dysplasia. Immunohistochemistry was rarely used to make the diagnosis of dysplasia and was thought not to be of help in routine practice. Inter-observer agreement in grading of dysplasia versus reactive, and the type of dysplasia (foveolar versus adenomatous), was substantial/almost perfect amongst 35.7% and 21.4% of participants, respectively. This reflects low reproducibility in making these diagnoses. In conclusion, foveolar dysplasia was a rarely made diagnosis among 14 gastrointestinal pathologists, there are no uniform criteria for diagnosis and there is poor inter-observer agreement in separating low-grade foveolar dysplasia from reactive gastric mucosa and low-grade adenomatous dysplasia. Greater awareness and agreed criteria will prevent misdiagnosis of low-grade foveolar dysplasia as reactive, and vice versa.


Asunto(s)
Esófago de Barrett/patología , Mucosa Gástrica/patología , Neoplasias Pancreáticas/patología , Gastropatías/patología , Femenino , Humanos , Inmunohistoquímica/métodos , Masculino , Variaciones Dependientes del Observador , Lesiones Precancerosas/patología , Reproducibilidad de los Resultados , Gastropatías/diagnóstico , Encuestas y Cuestionarios
5.
BMJ Open ; 5(5): e008097, 2015 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-25968008

RESUMEN

INTRODUCTION: Coeliac disease (CD) is an autoimmune condition characterised by gluten-induced intestinal inflammation, and observed at a 5-10 fold greater prevalence in type 1 diabetes. While universal screening for CD in patients with diabetes is frequently advocated, objective data is limited as to benefits on diabetes control, bone health or quality of life related to the adoption of a gluten-free diet (GFD) in the large proportion of patients with diabetes with asymptomatic CD. The Celiac Disease and Diabetes-Dietary Intervention and Evaluation Trial (CD-DIET) study is a multicenter, randomised controlled trial to evaluate the efficacy and safety of a GFD in patients with type 1 diabetes with asymptomatic CD. METHODS AND ANALYSIS: Children and adults (8-45 years) with type 1 diabetes will be screened for asymptomatic CD. Eligible patients with biopsy-proven CD will be randomly assigned in a 1:1 ratio to treatment with a GFD for 1 year, or continue with a gluten-containing diet. The primary outcome will evaluate the impact of the GFD on change in glycated haemoglobin. Secondary outcomes will evaluate changes in bone mineral density, blood glucose variability and health-related quality of life between GFD-treated and the regular diet group over a 1-year period. The study was initiated in 2012 and has subsequently expanded to multiple paediatric and adult centres in Ontario, Canada. ETHICS AND DISSEMINATION: The findings from this study will provide high-quality evidence as to the impact of GFD treatment on glycaemic control and complications in asymptomatic children and adults with CD and type 1 diabetes. TRIAL REGISTRATION NUMBER: NCT01566110.


Asunto(s)
Glucemia/metabolismo , Enfermedad Celíaca/complicaciones , Protocolos Clínicos , Diabetes Mellitus Tipo 1/complicaciones , Dieta Sin Gluten , Conducta Alimentaria , Hemoglobina Glucada/metabolismo , Adolescente , Adulto , Enfermedad Celíaca/dietoterapia , Niño , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/dietoterapia , Femenino , Glútenes/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Ontario , Calidad de Vida , Proyectos de Investigación , Adulto Joven
6.
Nat Med ; 20(1): 29-36, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24292392

RESUMEN

Tumor recurrence following treatment remains a major clinical challenge. Evidence from xenograft models and human trials indicates selective enrichment of cancer-initiating cells (CICs) in tumors that survive therapy. Together with recent reports showing that CIC gene signatures influence patient survival, these studies predict that targeting self-renewal, the key 'stemness' property unique to CICs, may represent a new paradigm in cancer therapy. Here we demonstrate that tumor formation and, more specifically, human colorectal CIC function are dependent on the canonical self-renewal regulator BMI-1. Downregulation of BMI-1 inhibits the ability of colorectal CICs to self-renew, resulting in the abrogation of their tumorigenic potential. Treatment of primary colorectal cancer xenografts with a small-molecule BMI-1 inhibitor resulted in colorectal CIC loss with long-term and irreversible impairment of tumor growth. Targeting the BMI-1-related self-renewal machinery provides the basis for a new therapeutic approach in the treatment of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/tratamiento farmacológico , Compuestos Heterocíclicos con 2 Anillos/farmacología , Recurrencia Local de Neoplasia/metabolismo , Células Madre Neoplásicas/metabolismo , Complejo Represivo Polycomb 1/metabolismo , Tiazoles/farmacología , Animales , Western Blotting , Bromodesoxiuridina , Línea Celular Tumoral , Citometría de Flujo , Vectores Genéticos/genética , Compuestos Heterocíclicos con 2 Anillos/uso terapéutico , Humanos , Luciferasas , Ratones Endogámicos NOD , Ratones SCID , Complejo Represivo Polycomb 1/antagonistas & inhibidores , Interferencia de ARN , ARN Interferente Pequeño/genética , Tiazoles/uso terapéutico
7.
Can J Gastroenterol ; 27(10): e25-30, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24106732

RESUMEN

BACKGROUND: Many consider histology to be the gold standard for Helicobacter pylori detection. Because the number and distribution of H pylori organisms vary, particularly in patients taking proton pump inhibitors (PPIs), the American Gastroenterological Association recommends discontinuing PPIs two weeks before endoscopy, and taking biopsies from both the body and antrum. OBJECTIVE: To assess the influence of clinical practice on the histopathological detection of H pylori infection. METHODS: Electronic patient records were evaluated for the sites of gastric sampling and PPI use at endoscopy. One hundred fifty cases with biopsies taken from both antrum and body were randomly selected for pathological re-review with special stains. The gastric regions sampled, H pylori distribution and influence of clinical factors on pathological interpretation were assessed. RESULTS: Between 2005 and 2010, 10,268 biopsies were taken to detect H pylori. Only one region was sampled in 60% of patients (antrum 47%, body 13%). Re-review of biopsies taken from both antrum and body indicated that the correct regions were sampled in only 85 (57%) patients. Of these, 54 were H pylori positive and 96 were H pylori negative. H pylori was present in the antrum in only 15% of the patients and body only in 21%. Of 96 H pylori-negative patients, two were reinterpreted as positive. Forty-seven per cent of patients were taking PPIs at endoscopy, contributing to both false-negative and false-positive diagnoses. CONCLUSION: Despite national and international guidelines for managing H pylori infection, the American Gastroenterological Association guidelines are infrequently adhered to, with PPIs frequently contributing to false diagnosis; sampling one region only increases the likelihood of missing active infection by at least 15%.


Asunto(s)
Biopsia/métodos , Endoscopía Gastrointestinal/métodos , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/aislamiento & purificación , Úlcera Gástrica/diagnóstico , Canadá , Medicina Basada en la Evidencia , Adhesión a Directriz , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Humanos , Inmunohistoquímica , Guías de Práctica Clínica como Asunto , Inhibidores de la Bomba de Protones/uso terapéutico , Antro Pilórico/microbiología , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/microbiología
8.
Virchows Arch ; 463(4): 593-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23913169

RESUMEN

von Hippel-Lindau (VHL) disease is a hereditary autosomal dominant disorder associated with deletions or mutations in the VHL tumor suppressor gene. Characteristically, up to 60 % of neuroendocrine tumors (NETs) associated with VHL disease display a spectrum of clear cell morphology including multivacuolated lipid-rich cell change. Unlike neurofibromatosis type 1 and multiple endocrine neoplasia type 1 syndromes, ampullary NETs have not been described in association with VHL disease. In this report, we discuss the features of an incidental ampullary clear cell NET occurring in a patient with pancreatic VHL disease including multiple pancreatic NETs. The ampullary lesion consisted of epithelial cells resembling lipoblasts or signet ring cells. In our case, all NETs showing clear cell change were positive for inhibin. While the underlying mechanism of this finding is largely unknown, it is of note that positivity for inhibin has not been observed in clear cell NETs associated with multiple endocrine neoplasia type 1 syndrome. Our case proves that NETs can develop in the ampullary region in patients with VHL; clear cell change can occur in these lesions and can mimic signet ring cell carcinoma. This issue is of clinical significance especially in small biopsy samples; thus, positivity for keratin alone should not be taken as evidence of an adenocarcinoma. Moreover, demonstration of inhibin expression in a NET with clear cell change along with other clinical stigmata should alert the diagnostician to the possibility of VHL disease. However, further larger series examining inhibin expression in both syndrome-related and sporadic clear cell NETs are needed to confirm our findings.


Asunto(s)
Ampolla Hepatopancreática/metabolismo , Neoplasias del Conducto Colédoco/metabolismo , Inhibinas/biosíntesis , Tumores Neuroendocrinos/metabolismo , Enfermedad de von Hippel-Lindau/complicaciones , Adenocarcinoma de Células Claras/complicaciones , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/patología , Ampolla Hepatopancreática/patología , Neoplasias del Conducto Colédoco/complicaciones , Neoplasias del Conducto Colédoco/patología , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Tumores Neuroendocrinos/complicaciones , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/patología , Enfermedad de von Hippel-Lindau/patología
10.
Virchows Arch ; 460(2): 151-5, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22241181

RESUMEN

To ascertain the approach and degree of consensus of pathologists in the handling and regression grading of colorectal cancer resection specimens treated with neoadjuvant chemoradiation, a ten-part questionnaire was circulated to 18 gastrointestinal pathologists in eight countries. The questions were specific and addressed pertinent issues related to colorectal cancer with neoadjuvant chemoradiation. There is a lack of consensus on how to handle the specimen, number of sections taken, correlation with pre- and post-operative radiological imaging, and especially, regression grading schema employed. Consensus in the form of guidelines is required so that the pathological assessment of these specimens will provide clinically relevant information for patient management, irrespective of location.


Asunto(s)
Adenocarcinoma/patología , Neoplasias Colorrectales/patología , Clasificación del Tumor/normas , Patología Quirúrgica/normas , Manejo de Especímenes/normas , Adenocarcinoma/terapia , Quimioradioterapia , Neoplasias Colorrectales/terapia , Recolección de Datos , Humanos , Terapia Neoadyuvante , Clasificación del Tumor/métodos , Manejo de Especímenes/métodos
11.
Hum Pathol ; 43(11): 1917-23, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22575264

RESUMEN

The aim of this study was to ascertain the level of concordance among gastrointestinal pathologists for regression grading in rectal cancers treated with neoadjuvant chemoradiation. Seventeen gastrointestinal pathologists participated using the Mandard, Dworak, and modified rectal cancer regression grading systems to grade 10 representative slides that were selected from 10 cases of rectal cancer treated with long-course neoadjuvant chemoradiation. The slides were scanned with a whole-slide scanner generating dynamic digitized images. The results showed very little concordance across the 3 grading systems, with κ values of 0.28, 0.35, and 0.38 for the Mandard, Dworak, and modified rectal cancer regression grading systems, respectively. In only 1 of 10 study cases was there unanimous grading concordance using the modified rectal cancer regression grading system. It was felt that these systems lacked precision and clarity for reproducible, accurate regression grading. The study concluded that there was a need for a simple, reproducible regression grading system with clear criteria, a cumulative or composite score taking into account all sections of the tumor bed that is sampled rather than the worst section (highest grade), and there should be a uniform method of sampling of these specimens.


Asunto(s)
Adenocarcinoma/patología , Neoplasias del Recto/patología , Adenocarcinoma/clasificación , Adenocarcinoma/terapia , Humanos , Interpretación de Imagen Asistida por Computador , Cooperación Internacional , Terapia Neoadyuvante , Clasificación del Tumor , Variaciones Dependientes del Observador , Neoplasias del Recto/clasificación , Neoplasias del Recto/terapia , Reproducibilidad de los Resultados
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