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1.
Nature ; 561(7721): E2, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29930351

RESUMEN

Change history: In this Letter, the Acknowledgements section should have included the following sentence: "The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.". This omission has been corrected online.

2.
Nature ; 556(7702): 469-472, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29695849

RESUMEN

Massive galaxy clusters have been found that date to times as early as three billion years after the Big Bang, containing stars that formed at even earlier epochs1-3. The high-redshift progenitors of these galaxy clusters-termed 'protoclusters'-can be identified in cosmological simulations that have the highest overdensities (greater-than-average densities) of dark matter4-6. Protoclusters are expected to contain extremely massive galaxies that can be observed as luminous starbursts 7 . However, recent detections of possible protoclusters hosting such starbursts8-11 do not support the kind of rapid cluster-core formation expected from simulations 12 : the structures observed contain only a handful of starbursting galaxies spread throughout a broad region, with poor evidence for eventual collapse into a protocluster. Here we report observations of carbon monoxide and ionized carbon emission from the source SPT2349-56. We find that this source consists of at least 14 gas-rich galaxies, all lying at redshifts of 4.31. We demonstrate that each of these galaxies is forming stars between 50 and 1,000 times more quickly than our own Milky Way, and that all are located within a projected region that is only around 130 kiloparsecs in diameter. This galaxy surface density is more than ten times the average blank-field value (integrated over all redshifts), and more than 1,000 times the average field volume density. The velocity dispersion (approximately 410 kilometres per second) of these galaxies and the enormous gas and star-formation densities suggest that this system represents the core of a cluster of galaxies that was already at an advanced stage of formation when the Universe was only 1.4 billion years old. A comparison with other known protoclusters at high redshifts shows that SPT2349-56 could be building one of the most massive structures in the Universe today.

3.
Nature ; 553(7686): 51-54, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29211721

RESUMEN

According to the current understanding of cosmic structure formation, the precursors of the most massive structures in the Universe began to form shortly after the Big Bang, in regions corresponding to the largest fluctuations in the cosmic density field. Observing these structures during their period of active growth and assembly-the first few hundred million years of the Universe-is challenging because it requires surveys that are sensitive enough to detect the distant galaxies that act as signposts for these structures and wide enough to capture the rarest objects. As a result, very few such objects have been detected so far. Here we report observations of a far-infrared-luminous object at redshift 6.900 (less than 800 million years after the Big Bang) that was discovered in a wide-field survey. High-resolution imaging shows it to be a pair of extremely massive star-forming galaxies. The larger is forming stars at a rate of 2,900 solar masses per year, contains 270 billion solar masses of gas and 2.5 billion solar masses of dust, and is more massive than any other known object at a redshift of more than 6. Its rapid star formation is probably triggered by its companion galaxy at a projected separation of 8 kiloparsecs. This merging companion hosts 35 billion solar masses of stars and has a star-formation rate of 540 solar masses per year, but has an order of magnitude less gas and dust than its neighbour and physical conditions akin to those observed in lower-metallicity galaxies in the nearby Universe. These objects suggest the presence of a dark-matter halo with a mass of more than 100 billion solar masses, making it among the rarest dark-matter haloes that should exist in the Universe at this epoch.

4.
J Neurosci ; 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35610051

RESUMEN

The robust, reciprocal anatomical connections between the cerebellum and contralateral sensorimotor cerebral hemisphere underscores the strong physiological interdependence between these two regions in relation to human behavior. Previous studies have shown that damage to sensorimotor cortex can result in a lasting reduction of cerebellar metabolism, the magnitude of which has been linked to poor rehabilitative outcomes. A better understanding of movement-related cerebellar physiology as well as cortico-cerebellar coherence (CCC) in the chronic, post-stroke state may be key to developing novel neuromodulatory techniques that promote upper limb motor rehabilitation. As a part of the first in-human phase-I trial investigating the effects of deep brain stimulation of the cerebellar dentate nucleus (DN) on chronic, post-stroke motor rehabilitation, we collected invasive recordings from DN and scalp EEG in subjects (both sexes) with middle cerebral artery stroke during a visuo-motor tracking task. We investigated the excitability of ipsilesional cortex, DN and the their interaction as a function of motor impairment and performance. Our results indicate that 1) event-related oscillations in the ipsilesional cortex and DN were significantly correlated at movement onset in the low-ß band, with moderately and severely impaired subjects showing desynchronization and synchronization, respectively. 2) Significant CCC was observed during isometric 'hold' period in the low-ß band, which was critical for maintaining task accuracy. Our findings support a strong coupling between ipsilesional cortex and DN in the low-ß band during motor control across all impairment levels which encourages the exploitation of the cerebello-thalamo-cortical pathway as a neuromodulation target to promote rehabilitation.Significance Statement:Cerebral infarct due to stroke can lead to lasting reduction in cerebellar metabolism resulting in poor rehabilitative outcomes. Thorough investigation of the cerebellar electrophysiology as well as cortico-cerebellar connectivity in humans that could provide key insights to facilitate development of novel neuromodulatory technologies, has been lacking. As a part of the first in-human phase-I trial investigating deep brain stimulation of the cerebellar dentate nucleus (DN) for chronic, post-stroke motor rehabilitation, we collected invasive recordings from DN and scalp EEG while stroke patients performed a motor task. Our data indicate strong coupling between ipsilesional sensorimotor cortex and DN in the low-ß band across all impairment levels encouraging the exploration of electrical stimulation of the DN.

5.
Clin Radiol ; 77(6): 399-408, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35177229

RESUMEN

Castleman Disease (CD) is a rare entity that typically presents as an enhancing nodal mass in the mediastinum or head and neck region on computed tomography (CT). It may manifest as unicentric or multicentric regions of lymph node enlargement. A key clinical issue in the context of CD is delayed diagnosis, which contributes adversely to patient outcome, given that accurate diagnosis facilitates earlier treatment of this curable disease. This article will address relevant imaging aspects, with reference to typical and atypical imaging features of CD, illustrated using examples from our specialist centre; the imaging journey for patients with CD; and will provide practical pointers to radiologists in differentiating CD from other benign and malignant causes of enhancing lymphadenopathy, including lymphoma and neoplastic adenopathy. We will also review current classification tools and staging challenges with reference to World Health Organization guidelines, International Working Group guidelines as well as the Lugano classification. Finally, we will discuss the potential role of additional imaging techniques in CD, highlighting novel imaging methods and expanded utilities from our specialist centre.


Asunto(s)
Enfermedad de Castleman , Linfadenopatía , Radiología , Enfermedad de Castleman/diagnóstico por imagen , Enfermedad de Castleman/patología , Diagnóstico Diferencial , Humanos , Linfadenopatía/diagnóstico por imagen , Radiografía , Tomografía Computarizada por Rayos X
6.
Clin Radiol ; 77(2): 79-87, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34579859

RESUMEN

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare but emerging T-cell non-Hodgkin lymphoma. It has two distinct subtypes, "effusion-only" or "mass-forming" disease, arising around implants in patients with in situ or previous history of textured-surface breast implants. The clinical, histopathological and imaging features are unique and nuanced as compared to primary breast malignancy and other lymphoma categories. Prompt recognition and diagnosis triggers referral to appropriate BIA-ALCL centres and initiation of treatment, with potential for excellent prognosis. Definitive management of both subtypes involves implant and capsule removal; systemic therapy is reserved for mass-forming disease and advanced-stage disease. There have been recent crucial advances in the diagnostic pathway, with publication of national and international guidelines: from the UK Medicines Healthcare products Regulatory Agency (MHRA) Plastic, Reconstructive and Aesthetic Surgery Expert Advisory Group (PRASEAG), and the United States National Comprehensive Cancer Network (NCCN). This review provides a practical guide to the clinical work-up of BIA-ALCL, enabling optimisation of the diagnostic imaging pathway, with representative cases.


Asunto(s)
Implantes de Mama/efectos adversos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/etiología , Diagnóstico por Imagen/métodos , Linfoma Anaplásico de Células Grandes/diagnóstico por imagen , Linfoma Anaplásico de Células Grandes/etiología , Mama/diagnóstico por imagen , Femenino , Humanos , Pronóstico
7.
Clin Radiol ; 76(11): 789-800, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34217434

RESUMEN

Chronic lymphocytic leukaemia (CLL) is the most common leukaemia in adults. It is a malignancy of CD5 B-cells characterised by small, mature-appearing lymphocytes accumulating in the blood, bone marrow, and lymphoid tissues. Richer transformation (RT) is an important adverse complication. Detection of RT is critical to allow initiation of appropriate therapy. CLL staging and response evaluation is complicated and nuanced. From our extensive tertiary centre experience of several hundred CLL cases over the last decade, we detail key computed tomography (CT) and positron-emission tomography (PET) imaging features of the natural history of CLL. The authors present an original imaging-based patient-management paradigm for the investigation of potential RT, which will inform global practice. Potential applications of whole-body diffusion weighted imaging, novel PET radiotracers, minimal residual disease, and ct-DNA are addressed.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/diagnóstico por imagen , Leucemia Linfocítica Crónica de Células B/patología , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Anciano , Progresión de la Enfermedad , Humanos , Persona de Mediana Edad
8.
Clin Radiol ; 76(5): 391.e1-391.e18, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33579517

RESUMEN

Non-Hodgkin's lymphoma (NHL) encompasses over 40 different haematological malignancies, including low and high-grade neoplasms, such as follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) respectively. A key clinical issue in the context of NHL is delayed and inaccurate diagnosis, which contributes adversely to patient morbidity and mortality. This article will address relevant imaging aspects, with particular reference to advancements in NHL imaging, including computed tomography (CT), integrated positron-emission tomography (PET)-CT, and magnetic resonance imaging (MRI). We provide multiparametric (anato-functional) imaging display items, including histological correlation. We will also introduce our original concept of "Specialist Integrated Haematological Malignancy Imaging Reporting" (SIHMIR), a paradigm shift in lymphoma radiology.


Asunto(s)
Linfoma no Hodgkin/diagnóstico por imagen , Linfoma no Hodgkin/patología , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Sistemas de Información Radiológica , Tomografía Computarizada por Rayos X/métodos , Humanos , Estadificación de Neoplasias
9.
Rep Prog Phys ; 83(7): 075101, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32303008

RESUMEN

This paper reviews optical fibre technology for local area optical communications systems. Technologies used in local systems include single and multimode fibre, single and multimode lasers, optical modulators, photodetectors, wavelength division multiplexing, multilevel modulation formats, electronic packet switching, electronic equalization and error correction. These methods have enabled the local area optical link data rate to increase from 0.1 Gb s-1 in 1990 to nearly a Tb s-1 in 2019. The challenges to increasing link data rates further, while reducing the transmitted power per bit, at reduced cost are discussed. Potential technical solutions and newly proposed methods which might address these challenges are highlighted.

10.
Ann Oncol ; 31(2): 246-256, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31959341

RESUMEN

BACKGROUND: The bevacizumab-Avastin® adjuVANT (AVANT) study did not meet its primary end point of improving disease-free survival (DFS) with the addition of bevacizumab to oxaliplatin-based chemotherapy in stage III colon cancer (CC). We report here the long-term survival results (S-AVANT). PATIENTS AND METHODS: Patients with curatively resected stage III CC were randomly assigned to FOLFOX4, FOLFOX4-bevacizumab, or XELOX-bevacizumab. RESULTS: A total of 2867 patients were randomized: FOLFOX4: n = 955, FOLFOX4-bevacizumab: n = 960, XELOX-bevacizumab: n = 952. With a median of 6.73 years follow-up (interquartile range 5.51-10.54), 672 patients died, of whom 198 (20.7%), 250 (26.0%), and 224 (23.5%) were in the FOLFOX4, FOLFOX4-bevacizumab, and XELOX-bevacizumab arms, respectively. The 10-year overall survival (OS) rates were 74.6%, 67.2%, and 69.9%, (P = 0.003) and 5-year disease-free survival (DFS) rates were 73.2%, 68.5%, and 71.0% (P = 0.174), respectively. OS and DFS hazard ratios were 1.29 [95% confidence interval (CI) 1.07-1.55; P = 0.008] and 1.16 (95% CI 0.99-1.37; P = 0.063) for FOLFOX4-bevacizumab versus FOLFOX4 and 1.15 (95% CI 0.95-1.39; P = 0.147) and 1.1 (95% CI 0.93-1.29; P = 0.269) for XELOX-bevacizumab versus FOLFOX4, respectively. CC-related deaths (n = 542) occurred in 157 (79.3%) patients receiving FOLFOX4, 205 (82.0%) receiving FOLFOX4-bevacizumab, and 180 (80.4%) receiving XELOX-bevacizumab (P = 0.764), while non-CC-related deaths occurred in 41 (20.7%), 45 (18.0%), and 44 (19.6%) patients, respectively. Cardiovascular-related and sudden deaths during treatment or follow-up were reported in 13 (6.6%), 17 (6.8%), and 14 (6.3%) patients, in the FOLFOX4, FOLFOX4-bevacizuamb, and XELOX-bevacizumab arms, respectively (P = 0.789). Treatment arm, sex, age, histological differentiation, performance status, T/ N stages, and localization of primary tumor were independent prognostic factors of OS in stage III. CONCLUSIONS: S-AVANT confirms the initial AVANT report. No benefit of the bevacizumab addition to FOLFOX4 adjuvant therapy in patients with stage III CC was observed in terms of DFS with a negative effect in OS, without increase in non-CC related deaths. CLINICAL TRIAL IDENTIFICATION: NCT00112918.


Asunto(s)
Neoplasias del Colon , Compuestos Organoplatinos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bevacizumab/efectos adversos , Quimioterapia Adyuvante , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Supervivencia sin Enfermedad , Fluorouracilo/efectos adversos , Humanos , Leucovorina/efectos adversos , Estadificación de Neoplasias , Compuestos Organoplatinos/efectos adversos
11.
Br J Surg ; 107(13): 1801-1810, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32990343

RESUMEN

BACKGROUND: The role of adjuvant therapy in patients with oesophagogastric adenocarcinoma treated by neoadjuvant chemotherapy is contentious. In UK practice, surgical resection margin status is often used to classify patients for receiving adjuvant treatment. The aim of this study was to assess the survival benefit of adjuvant therapy in patients with positive (R1) resection margins. METHODS: Two prospectively collected UK institutional databases were combined to identify eligible patients. Adjusted Cox regression analyses were used to compare overall and recurrence-free survival according to adjuvant treatment. Recurrence patterns were assessed as a secondary outcome. Propensity score-matched analysis was also performed. RESULTS: Of 616 patients included in the combined database, 242 patients who had an R1 resection were included in the study. Of these, 112 patients (46·3 per cent) received adjuvant chemoradiotherapy, 46 (19·0 per cent) were treated with adjuvant chemotherapy and 84 (34·7 per cent) had no adjuvant treatment. In adjusted analysis, adjuvant chemoradiotherapy improved recurrence-free survival (hazard ratio (HR) 0·59, 95 per cent c.i. 0·38 to 0·94; P = 0·026), with a benefit in terms of both local (HR 0·48, 0·24 to 0·99; P = 0·047) and systemic (HR 0·56, 0·33 to 0·94; P = 0·027) recurrence. In analyses stratified by tumour response to neoadjuvant chemotherapy, non-responders (Mandard tumour regression grade 4-5) treated with adjuvant chemoradiotherapy had an overall survival benefit (HR 0·61, 0·38 to 0·97; P = 0·037). In propensity score-matched analysis, an overall survival benefit (HR 0·62, 0·39 to 0·98; P = 0·042) and recurrence-free survival benefit (HR 0·51, 0·30 to 0·87; P = 0·004) were observed for adjuvant chemoradiotherapy versus no adjuvant treatment. CONCLUSION: Adjuvant therapy may improve overall survival and recurrence-free survival after margin-positive resection. This pattern seems most pronounced with adjuvant chemoradiotherapy in non-responders to neoadjuvant chemotherapy.


ANTECEDENTES: El papel del tratamiento adyuvante en pacientes con adenocarcinoma esofagogástrico tratados con quimioterapia neoadyuvante es polémico. En la práctica del Reino Unido, el estado del margen de resección quirúrgico se utiliza a menudo para identificar a los pacientes que reciben tratamiento adyuvante. El objetivo de este estudio fue evaluar el beneficio en la supervivencia del tratamiento adyuvante en pacientes con márgenes de resección positivos (R1). MÉTODOS: Se combinaron dos bases de datos de instituciones del Reino Unido que recogen información de forma prospectiva para identificar pacientes elegibles. Se utilizaron análisis de regresión de Cox ajustados para comparar la supervivencia global y la supervivencia libre de recidiva según el tratamiento adyuvante. Los patrones de recidiva se evaluaron como resultado secundario. También se realizó un análisis de emparejamiento por puntaje de propensión. RESULTADOS: De 616 pacientes incluidos en la base de datos combinada, se incluyeron en el estudio 242 pacientes con resección R1. De estos pacientes, 112 (46%) recibieron quimiorradioterapia adyuvante, 46 (19%) pacientes fueron tratados con quimioterapia adyuvante y 84 (35%) pacientes no recibieron ningún tratamiento. En el análisis ajustado, la quimiorradioterapia adyuvante mejoró la supervivencia libre de recidiva (cociente de riesgos instantáneos, hazard ratio, HR 0,59, i.c. del 95% 0,38-0,94; P = 0,026) con un beneficio tanto para la recidiva local (HR 0,48, i.c. del 95% 0,24-0,99; P = 0,047) como para la sistémica (HR 0,56, i.c. del 95% 0,33-0,94; P = 0,027). Cuando los pacientes se clasificaron según la respuesta tumoral a la quimioterapia neoadyuvante, los no respondedores (Mandard Grado 4/5) tratados con quimiorradioterapia adyuvante obtuvieron un beneficio en la supervivencia (HR 0,61, i.c. del 95% 0,38-0,97; P = 0,037). En el análisis por emparejamiento por puntaje de propensión, se observó un beneficio en la supervivencia global (HR 0,62, i.c. del 95% 0,39-0,98; P = 0,042) y en la supervivencia libre de recidiva (HR 0,51.i.c. del 95% 0,30-0,87; P = 0,004) con la quimiorradioterapia adyuvante frente a no recibir tratamiento adyuvante. CONCLUSIÓN: El tratamiento adyuvante puede mejorar la supervivencia global y la supervivencia libre de recidiva en pacientes con margen de resección positivo. Este patrón parece más pronunciado con la quimiorradioterapia adyuvante en pacientes que no responden a la quimioterapia.


Asunto(s)
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia Adyuvante , Quimioterapia Adyuvante , Neoplasias Esofágicas/terapia , Esofagectomía , Márgenes de Escisión , Adenocarcinoma/patología , Adulto , Anciano , Antineoplásicos/uso terapéutico , Neoplasias Esofágicas/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Puntaje de Propensión , Estudios Retrospectivos , Análisis de Supervivencia
12.
Colorectal Dis ; 22(10): 1231-1244, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31999888

RESUMEN

AIM: The aim was to assess the benefit of adjuvant chemotherapy in high-risk Stage II colorectal cancer. METHOD: A systematic literature review and meta-analysis was performed comparing survival in patients with resected Stage II colorectal cancer and high-risk features having postoperative chemotherapy vs no chemotherapy. RESULTS: Of 1031 articles screened, 29 were included, reporting on 183 749 participants. Adjuvant chemotherapy significantly improved overall survival [hazard ratio (HR) 0.61, P < 0.0001], disease-specific survival (HR = 0.73, P = 0.05) and disease-free survival (HR = 0.59, P < 0.0001) compared to no chemotherapy. Adjuvant chemotherapy significantly increased 5-year overall survival (OR = 0.53, P = 0.0008) and 5-year disease-free survival (OR = 0.50, P = 0.001). Overall survival and disease-free survival remained significantly prolonged during subgroup analysis of studies published from 2015 onwards (HR = 0.60, P < 0.0001; HR = 0.65, P = 0.0001; respectively), in patients with two or more high-risk features (HR = 0.59, P = 0.0001; HR = 0.70, P = 0.03; respectively) and in colon cancer (HR = 0.61, P < 0.0001; HR = 0.51, P = 0.0001; respectively). Overall survival, disease-specific survival and disease-free survival during subgroup analysis of individual high-risk features were T4 tumour (HR = 0.58, P < 0.0001; HR = 0.50, P = 0.003; HR = 0.75, P = 0.05), < 12 lymph nodes harvested (HR = 0.67, P = 0.0002; HR = 0.80, P = 0.17; HR = 0.72, P = 0.02), poor differentiation (HR = 0.84, P = 0.35; HR = 0.85, P = 0.23; HR = 0.61, P = 0.41), lymphovascular or perineural invasion (HR = 0.55, P = 0.05; HR = 0.59, P = 0.11; HR = 0.76, P = 0.05) and emergency surgery (HR = 0.60, P = 0.02; HR = 0.68, P = 0.19). CONCLUSION: Adjuvant chemotherapy in high-risk Stage II colorectal cancer results in a modest survival improvement and should be considered on an individual patient basis. Due to potential heterogeneity and selection bias of the included studies, and lack of separate rectal cancer data, further large randomized trials with predefined inclusion criteria and standardized chemotherapy regimens are required.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Quimioterapia Adyuvante , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/cirugía , Supervivencia sin Enfermedad , Humanos , Neoplasias del Recto/tratamiento farmacológico
13.
Br J Surg ; 106(9): 1204-1215, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31268180

RESUMEN

BACKGROUND: The UK Medical Research Council ST03 trial compared perioperative epirubicin, cisplatin and capecitabine (ECX) chemotherapy with or without bevacizumab (B) in gastric and oesophagogastric junctional cancer. No difference in survival was noted between the arms of the trial. The present study reviewed the standards and performance of surgery in the context of the protocol-specified surgical criteria. METHODS: Surgical and pathological clinical report forms were reviewed to determine adherence to the surgical protocols, perioperative morbidity and mortality, and final histopathological stage for all patients treated in the study. RESULTS: Of 1063 patients randomized, 895 (84·2 per cent) underwent resection; surgical details were available for 880 (98·3 per cent). Postoperative assessment data were available for 873 patients; complications occurred in 458 (52·5 per cent) overall, of whom 71 (8·1 per cent) developed complications deemed to be life-threatening by the responsible clinician. The most common complications were respiratory (211 patients, 24·2 per cent). The anastomotic leak rate was 118 of 873 (13·5 per cent) overall; among those who underwent oesophagogastrectomy, the rate was higher in the group receiving ECX-B (23·6 per cent versus 9·9 per cent in the ECX group). Pathological assessment data were available for 845 patients. At least 15 nodes were removed in 82·5 per cent of resections and the median lymph node harvest was 24 (i.q.r. 17-34). Twenty-five or more nodes were removed in 49·0 per cent of patients. Histopathologically, the R1 rate was 24·9 per cent (208 of 834 patients). An R1 resection was more common for proximal tumours. CONCLUSION: In the ST03 trial, the performance of surgery met the protocol-stipulated criteria. Registration number: NCT00450203 ( http://www.clinicaltrials.gov).


Asunto(s)
Adenocarcinoma/cirugía , Unión Esofagogástrica , Garantía de la Calidad de Atención de Salud , Neoplasias Gástricas/cirugía , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bevacizumab/administración & dosificación , Bevacizumab/uso terapéutico , Capecitabina/administración & dosificación , Capecitabina/uso terapéutico , Cisplatino/administración & dosificación , Cisplatino/uso terapéutico , Protocolos Clínicos/normas , Terapia Combinada , Epirrubicina/administración & dosificación , Epirrubicina/uso terapéutico , Unión Esofagogástrica/cirugía , Gastrectomía/efectos adversos , Gastrectomía/métodos , Gastrectomía/normas , Humanos , Garantía de la Calidad de Atención de Salud/métodos , Estómago/cirugía , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/terapia
14.
Br J Surg ; 106(4): 384-394, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30566233

RESUMEN

BACKGROUND: High rates of reoperation following breast-conserving surgery (BCS) for positive margins are associated with costs to healthcare providers. The aim was to assess the quality of evidence on reported re-excision costs and compare the direct patient-level costs between patients undergoing successful BCS versus reoperations after BCS. METHODS: The study used data from women who had BCS with or without reoperation at a single institution between April 2015 and March 2016. A systematic review of health economic analysis in BCS was conducted and scored using the Quality of Health Economic Studies (QHES) instrument. Financial data were retrieved using the Patient-Level Information and Costing Systems (PLICS) for patients. Exchange rates used were: US $1 = £0·75, £1 = €1·14 and US $1 = €0·85. RESULTS: The median QHES score was 47 (i.q.r. 32·5-79). Only two of nine studies scored in the upper QHES quartile (score at least 75). Costs of initial lumpectomy and reoperation were in the range US $1234-11786 and $655-9136 respectively. Over a 12-month interval, 153 patients had definitive BCS and 59 patients underwent reoperation. The median cost of reoperations after BCS (59 patients) was £4511 (range 1752-18 019), representing an additional £2136 per patient compared with BCS without reoperation (P < 0·001). CONCLUSION: The systematic review demonstrated variation in methodological approach to cost estimates and a paucity of high-quality cost estimate studies for reoperations. Extrapolating local PLICS data to a national level suggests that getting BCS right first time could result in substantial savings.


Asunto(s)
Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Costo de Enfermedad , Márgenes de Escisión , Mastectomía Segmentaria/efectos adversos , Reoperación/economía , Adulto , Anciano , Análisis de Varianza , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/mortalidad , Carcinoma Ductal de Mama/patología , Bases de Datos Factuales , Femenino , Costos de la Atención en Salud , Humanos , Modelos Lineales , Mastectomía Segmentaria/métodos , Persona de Mediana Edad , Análisis Multivariante , Reoperación/métodos , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento
15.
Ann Oncol ; 29(6): 1377-1385, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29771279

RESUMEN

Surgery represents the only chance of cure for patients with gastroesophageal adenocarcinoma; however, surgery alone does not cure most patients. Over the past decade, several multimodality adjunctive treatments have improved survival for patients with operable gastroesophageal adenocarcinoma who are undergoing surgical resection; these include peri-operative chemotherapy, neoadjuvant chemoradiotherapy, adjuvant chemotherapy and adjuvant chemoradiotherapy. More recently, the results of several large randomised trials are leading to a shift in the peri-operative treatment of gastroesophageal cancer, away from anthracycline-based and towards taxane-based chemotherapy regimens. Emerging data support an increased focus on patients who are at high risk for poor operative outcomes such as R1 resection, and on patients who are at high risk for relapse following surgery such as those with lymph node metastases (N1+). Future developments may include use of fluorodeoxyglucose-positron emission tomography to inform a switch to non-cross resistant chemotherapy pre-operatively and substitution of alternative treatments for chemotherapy in high risk post-operative node positive patients. Conversely, in molecularly selected subgroups such as microsatellite unstable gastroesophageal cancer, peri-operative or adjuvant chemotherapy may not be helpful, and treatments such as immunotherapy may be considered. In this review, the most up-to-date clinical trials and translational research in the field of operable gastroesophageal cancer are discussed; with a focus on how best to risk stratify patients with operable disease for peri-operative treatment plus surgery, and how novel therapies might be integrated into standard treatments in order to improve survival outcomes in this patient group.


Asunto(s)
Adenocarcinoma/terapia , Neoplasias Esofágicas/terapia , Unión Esofagogástrica/patología , Neoplasias Gástricas/terapia , Adenocarcinoma/patología , Animales , Terapia Combinada , Neoplasias Esofágicas/patología , Humanos , Pronóstico , Neoplasias Gástricas/patología
16.
Ann Oncol ; 29(8): 1822-1827, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29897404

RESUMEN

Background: Patients with diffuse large B-cell lymphoma treated with first-line anthracycline-based immunochemotherapy and remaining in remission at 2 years have excellent outcomes. This study assessed overall survival (OS) stratified by progression-free survival (PFS) at 24 months (PFS24) using individual patient data from patients with DLBCL enrolled in multi-center, international randomized clinical trials as part of the Surrogate Endpoint for Aggressive Lymphoma (SEAL) Collaboration. Patients and methods: PFS24 was defined as being alive and PFS24 after study entry. OS from PFS24 was defined as time from identified PFS24 status until death due to any cause. OS was compared with each patient's age-, sex-, and country-matched general population using expected survival and standardized mortality ratios (SMRs). Results: A total of 5853 patients enrolled in trials in the SEAL database received rituximab as part of induction therapy and were included in this analysis. The median age was 62 years (range 18-92), and 56% were greater than 60 years of age. At a median follow-up of 4.4 years, 1337 patients (23%) had disease progression, 1489 (25%) had died, and 5101 had sufficient follow-up to evaluate PFS24. A total of 1423 assessable patients failed to achieve PFS24 with a median OS of 7.2 months (95% CI 6.8-8.1) after progression; 5-year OS after progression was 19% and SMR was 32.1 (95% CI 30.0-34.4). A total of 3678 patients achieved PFS24; SMR after achieving PFS24 was 1.22 (95% CI 1.09-1.37). The observed OS versus expected OS at 3, 5, and 7 years after achieving PFS24 was 93.1% versus 94.4%, 87.6% versus 89.5%, and 80.0% versus 83.7%, respectively. Conclusion: Patients treated with rituximab containing anthracycline-based immunochemotherapy on clinical trials who are alive without progression at 24 months from the onset of initial therapy have excellent outcomes with survival that is marginally lower but clinically indistinguishable from the age-, sex-, and country-matched background population for 7 years after achieving PFS24.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma de Células B Grandes Difuso/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antraciclinas/uso terapéutico , Bases de Datos Factuales/estadística & datos numéricos , Progresión de la Enfermedad , Femenino , Humanos , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/patología , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Supervivencia sin Progresión , Ensayos Clínicos Controlados Aleatorios como Asunto , Rituximab/uso terapéutico , Adulto Joven
17.
Ann Oncol ; 29(12): 2356-2362, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30481267

RESUMEN

Background: Following neoadjuvant chemotherapy for operable gastroesophageal cancer, lymph node metastasis is the only validated prognostic variable; however, within lymph node groups there is still heterogeneity with risk of relapse. We hypothesized that gene profiles from neoadjuvant chemotherapy treated resection specimens from gastroesophageal cancer patients can be used to define prognostic risk groups to identify patients at risk for relapse. Patients and methods: The Medical Research Council Adjuvant Gastric Infusional Chemotherapy (MAGIC) trial (n = 202 with high quality RNA) samples treated with perioperative chemotherapy were profiled for a custom gastric cancer gene panel using the NanoString platform. Genes associated with overall survival (OS) were identified using penalized and standard Cox regression, followed by generation of risk scores and development of a NanoString biomarker assay to stratify patients into risk groups associated with OS. An independent dataset served as a validation cohort. Results: Regression and clustering analysis of MAGIC patients defined a seven-Gene Signature and two risk groups with different OS [hazard ratio (HR) 5.1; P < 0.0001]. The median OS of high- and low-risk groups were 10.2 [95% confidence interval (CI) of 6.5 and 13.2 months] and 80.9 months (CI: 43.0 months and not assessable), respectively. Risk groups were independently prognostic of lymph node metastasis by multivariate analysis (HR 3.6 in node positive group, P = 0.02; HR 3.6 in high-risk group, P = 0.0002), and not prognostic in surgery only patients (n = 118; log rank P = 0.2). A validation cohort independently confirmed these findings. Conclusions: These results suggest that gene-based risk groups can independently predict prognosis in gastroesophageal cancer patients treated with neoadjuvant chemotherapy. This signature and associated assay may help risk stratify these patients for post-surgery chemotherapy in future perioperative chemotherapy-based clinical trials.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/genética , Neoplasias Esofágicas/terapia , Recurrencia Local de Neoplasia/prevención & control , Neoplasias Gástricas/terapia , Transcriptoma/genética , Adulto , Anciano , Quimioterapia Adyuvante/métodos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Esofagectomía , Esófago/patología , Esófago/cirugía , Femenino , Gastrectomía , Perfilación de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Pronóstico , Estudios Prospectivos , Medición de Riesgo/métodos , Estómago/patología , Estómago/cirugía , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Resultado del Tratamiento
18.
Ann Oncol ; 29(1): 230-236, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29361134

RESUMEN

Background: Targeted capture sequencing can potentially facilitate precision medicine, but the feasibility of this approach in gastrointestinal (GI) malignancies is unknown. Patients and methods: The FOrMAT (Feasibility of a Molecular Characterisation Approach to Treatment) study was a feasibility study enrolling patients with advanced GI malignancies from February 2014 to November 2015. Targeted capture sequencing (mainly using archival formalin-fixed paraffin-embedded diagnostic/resection samples) was carried out to detect mutations, copy number variations and translocations in up to 46 genes which had prognostic/predictive significance or were targets in current/upcoming clinical trials. Results: Of the 222 patients recruited, 215 patients (96.8%) had available tissue samples, 125 patients (56.3%) had ≥16 genes successfully sequenced and 136 patients (61.2%) had ≥1 genes successfully sequenced. Sample characteristics influenced the proportion of successfully sequenced samples, e.g. tumour type (colorectal 70.9%, biliary 52.6%, oesophagogastric 50.7%, pancreas 27.3%, P = 0.002), tumour cellularity (high versus low: 78.3% versus 13.3%, P ≤ 0.001), tumour content (high versus low: 78.6% versus 27.3%, P = 0.001) and type of sample (resection versus biopsy: 82.4% versus 47.6%, P ≤ 0.001). Currently, actionable alterations were detected in 90 (40.5%) of the 222 patients recruited (66% of the 136 patients sequenced) and 2 patients subsequently received a targeted therapy. The most frequently detected currently actionable alterations were mutations in KRAS, BRAF, TP53 and PIK3CA. For the 205 patients with archival samples, the median time to obtain sequencing results was 18.9 weeks, including a median of 4.9 weeks for sample retrieval and 5.1 weeks for sequencing. Conclusions: Targeted sequencing detected actionable alterations in formalin-fixed paraffin-embedded samples, but tissue characteristics are of critical importance in determining sequencing success. Routine molecular profiling of GI tumours outside of clinical trials is not an effective use of healthcare resources unless more targeted drugs become available. ClinicalTrials.gov identifier: NCT02112357.


Asunto(s)
Análisis Mutacional de ADN/métodos , Neoplasias Gastrointestinales/genética , Mutación , Análisis de Secuencia de ADN/métodos , ADN de Neoplasias/química , ADN de Neoplasias/genética , Estudios de Factibilidad , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos
19.
Br J Surg ; 105(12): 1615-1622, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29993125

RESUMEN

BACKGROUND: Surgical subspecialization has resulted in mastitis and breast abscesses being managed with unnecessary admission to hospital, prolonged inpatient stay, variable antibiotic prescribing, incision and drainage rather than percutaneous aspiration, and loss to specialist follow-up. The objective was to evaluate a best-practice algorithm with the aim of improving management of mastitis and breast abscesses across a multisite NHS Trust. The focus was on uniformity of antibiotic prescribing, ultrasound assessment, admission rates, length of hospital stay, intervention by aspiration or incision and drainage, and specialist follow-up. METHODS: Management was initially evaluated in a retrospective cohort (phase I) and subsequently compared with that in two prospective cohorts after introduction of a breast abscess and mastitis pathway. One prospective cohort was analysed immediately after introduction of the pathway (phase II), and the second was used to assess the sustainability of the quality improvements (phase III). The overall impact of the pathway was assessed by comparing data from phase I with combined data from phases II and III; results from phases II and III were compared to judge sustainability. RESULTS: Fifty-three patients were included in phase I, 61 in phase II and 80 in phase III. The management pathway and referral pro forma improved compliance with antibiotic guidelines from 34 per cent to 58·2 per cent overall (phases II and III) after implementation (P = 0·003). The improvement was maintained between phases II and III (54 and 61 per cent respectively; P = 0·684). Ultrasound assessment increased from 38 to 77·3 per cent overall (P < 0·001), in a sustained manner (75 and 79 per cent in phases II and III respectively; P = 0·894). Reductions in rates of incision and drainage (from 8 to 0·7 per cent overall; P = 0·007) were maintained (0 per cent in phase II versus 1 per cent in phase III; P = 0·381). Specialist follow-up improved consistently from 43 to 95·7 per cent overall (P < 0·001), 92 per cent in phase II and 99 per cent in phase III (P = 0·120). Rates of hospital admission and median length of stay were not significantly reduced after implementation of the pathway. CONCLUSION: A standardized approach to mastitis and breast abscess reduced undesirable practice variation, with sustained improvements in process and patient outcomes.


Asunto(s)
Absceso/terapia , Enfermedades de la Mama/terapia , Pautas de la Práctica en Medicina/normas , Absceso/diagnóstico por imagen , Cuidados Posteriores/estadística & datos numéricos , Antibacterianos/uso terapéutico , Enfermedades de la Mama/diagnóstico por imagen , Protocolos Clínicos , Vías Clínicas , Drenaje/métodos , Femenino , Adhesión a Directriz , Hospitalización/estadística & datos numéricos , Humanos , Tiempo de Internación , Mastitis/diagnóstico por imagen , Mastitis/terapia , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Ultrasonografía Mamaria
20.
Br J Surg ; 105(12): 1639-1649, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30047556

RESUMEN

BACKGROUND: The aim was to define the pathological response in lymph nodes following neoadjuvant chemotherapy for oesophageal adenocarcinoma and to quantify any associated survival benefit. METHODS: Lymph nodes retrieved at oesophagectomy were examined retrospectively by two pathologists for evidence of a response to chemotherapy. Patients were classified as lymph node-negative (either negative nodes with no evidence of previous tumour involvement or negative with evidence of complete regression) or positive (allocated a lymph node regression score based on the proportion of fibrosis to residual tumour). Lymph node responders (score 1, complete response; 2, less than 10 per cent remaining tumour; 3, 10-50 per cent remaining tumour) and non-responders (score 4, more than 50 per cent viable tumour; 5, no response) were compared in survival analyses using Kaplan-Meier and Cox regression analysis. RESULTS: Among 377 patients, 256 had neoadjuvant chemotherapy. Overall, 68 of 256 patients (26·6 per cent) had a lymph node response and 115 (44·9 per cent) did not. The remaining 73 patients (28·5 per cent) had negative lymph nodes with no evidence of regression. Some patients had a lymph node response in the absence of a response in the primary tumour (27 of 99, 27 per cent). Lymph node responders had a significant survival benefit (P < 0·001), even when stratified by patients with or without a response in the primary tumour. On multivariable analysis, lymph node responders had decreased overall (hazard ratio 0·53, 95 per cent c.i. 0·36 to 0·78) and disease-specific (HR 0·42, 0·27 to 0·66) mortality, and experienced reduced local and systemic recurrence. CONCLUSION: Lymph node regression is a strong prognostic factor and may be more important than response in the primary tumour.


Asunto(s)
Adenocarcinoma/terapia , Quimioterapia Adyuvante/métodos , Neoplasias Esofágicas/terapia , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Quimioterapia Adyuvante/mortalidad , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Esofagectomía/mortalidad , Femenino , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Terapia Neoadyuvante/mortalidad , Clasificación del Tumor , Recurrencia Local de Neoplasia/mortalidad , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento
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