Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Int J Surg ; 110(4): 1983-1991, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241421

RESUMO

BACKGROUND: Colorectal cancer is the third most commonly diagnosed malignancy and the second leading cause of mortality worldwide. A positive resection margin following surgery for colorectal cancer is linked with higher rates of local recurrence and poorer survival. The authors investigated diffuse reflectance spectroscopy (DRS) to distinguish tumour and non-tumour tissue in ex-vivo colorectal specimens, to aid margin assessment and provide augmented visual maps to the surgeon in real-time. METHODS: Patients undergoing elective colorectal cancer resection surgery at a London-based hospital were prospectively recruited. A hand-held DRS probe was used on the surface of freshly resected ex-vivo colorectal tissue. Spectral data were acquired for tumour and non-tumour tissue. Binary classification was achieved using conventional machine learning classifiers and a convolutional neural network (CNN), which were evaluated in terms of sensitivity, specificity, accuracy and the area under the curve. RESULTS: A total of 7692 mean spectra were obtained for tumour and non-tumour colorectal tissue. The CNN-based classifier was the best performing machine learning algorithm, when compared to contrastive approaches, for differentiating tumour and non-tumour colorectal tissue, with an overall diagnostic accuracy of 90.8% and area under the curve of 96.8%. Live on-screen classification of tissue type was achieved using a graduated colourmap. CONCLUSION: A high diagnostic accuracy for a DRS probe and tracking system to differentiate ex-vivo tumour and non-tumour colorectal tissue in real-time with on-screen visual feedback was highlighted by this study. Further in-vivo studies are needed to ensure integration into a surgical workflow.


Assuntos
Neoplasias Colorretais , Margens de Excisão , Redes Neurais de Computação , Análise Espectral , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/classificação , Feminino , Masculino , Estudos Prospectivos , Idoso , Análise Espectral/métodos , Pessoa de Meia-Idade , Aprendizado de Máquina , Idoso de 80 Anos ou mais
2.
Int J Comput Assist Radiol Surg ; 19(1): 11-14, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37289279

RESUMO

PURPOSE: A positive circumferential resection margin (CRM) for oesophageal and gastric carcinoma is associated with local recurrence and poorer long-term survival. Diffuse reflectance spectroscopy (DRS) is a non-invasive technology able to distinguish tissue type based on spectral data. The aim of this study was to develop a deep learning-based method for DRS probe detection and tracking to aid classification of tumour and non-tumour gastrointestinal (GI) tissue in real time. METHODS: Data collected from both ex vivo human tissue specimen and sold tissue phantoms were used for the training and retrospective validation of the developed neural network framework. Specifically, a neural network based on the You Only Look Once (YOLO) v5 network was developed to accurately detect and track the tip of the DRS probe on video data acquired during an ex vivo clinical study. RESULTS: Different metrics were used to analyse the performance of the proposed probe detection and tracking framework, such as precision, recall, mAP 0.5, and Euclidean distance. Overall, the developed framework achieved a 93% precision at 23 FPS for probe detection, while the average Euclidean distance error was 4.90 pixels. CONCLUSION: The use of a deep learning approach for markerless DRS probe detection and tracking system could pave the way for real-time classification of GI tissue to aid margin assessment in cancer resection surgery and has potential to be applied in routine surgical practice.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Neoplasias Gastrointestinais , Humanos , Estudos Retrospectivos , Análise Espectral , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/cirurgia , Redes Neurais de Computação
3.
BMC Med ; 21(1): 383, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794461

RESUMO

BACKGROUND: An increased number of resources are allocated on cancer biomarker discovery, but very few of these biomarkers are clinically adopted. To bridge the gap between Biomarker discovery and clinical use, we aim to generate the Biomarker Toolkit, a tool designed to identify clinically promising biomarkers and promote successful biomarker translation. METHODS: All features associated with a clinically useful biomarker were identified using mixed-methodology, including systematic literature search, semi-structured interviews, and an online two-stage Delphi-Survey. Validation of the checklist was achieved by independent systematic literature searches using keywords/subheadings related to clinically and non-clinically utilised breast and colorectal cancer biomarkers. Composite aggregated scores were generated for each selected publication based on the presence/absence of an attribute listed in the Biomarker Toolkit checklist. RESULTS: Systematic literature search identified 129 attributes associated with a clinically useful biomarker. These were grouped in four main categories including: rationale, clinical utility, analytical validity, and clinical validity. This checklist was subsequently developed using semi-structured interviews with biomarker experts (n=34); and 88.23% agreement was achieved regarding the identified attributes, via the Delphi survey (consensus level:75%, n=51). Quantitative validation was completed using clinically and non-clinically implemented breast and colorectal cancer biomarkers. Cox-regression analysis suggested that total score is a significant driver of biomarker success in both cancer types (BC: p>0.0001, 95.0% CI: 0.869-0.935, CRC: p>0.0001, 95.0% CI: 0.918-0.954). CONCLUSIONS: This novel study generated a validated checklist with literature-reported attributes linked with successful biomarker implementation. Ultimately, the application of this toolkit can be used to detect biomarkers with the highest clinical potential and shape how biomarker studies are designed/performed.


Assuntos
Pesquisa Biomédica , Neoplasias Colorretais , Humanos , Biomarcadores Tumorais/genética , Lista de Checagem , Neoplasias Colorretais/diagnóstico
4.
Front Digit Health ; 5: 1242896, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37829594

RESUMO

Introduction: In the midst of a global climate emergency and with health care systems across the world facing extreme pressure, interest in digital approaches as a potential part-solution to these challenges has increased rapidly. The evidence base to support the role that digitalization can play in moving towards more sustainable models of healthcare is growing, as is the awareness of this key area of healthcare reform amongst policy makers, clinicians and the public. Method and Results: In this policy and practice review we explore four domains of healthcare sustainability-environmental, economic, and patient and clinician, delineating the potential impact that digitally enabled healthcare can have on each area. Real-world examples are provided to illustrate the impact individual digital interventions can have on each pillar of sustainability and demonstrate the scale of the potential benefits which can be achieved. Discussion: Digitally enabled healthcare solutions present an approach which offer numerous benefits, including environmental sustainability, economic benefits, and improved patient experience. There are also potential drawbacks such as the risk of digital exclusion and the need for integration with existing technology platforms. Overall, it is essential to strike a balance between the benefits and potential drawbacks of digital healthcare solutions to ensure that they are equitable, effective, and sustainable.

6.
Curr Oncol ; 30(2): 1673-1682, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36826089

RESUMO

BACKGROUND: Home-based and supervised prehabilitation programmes are shown to have a positive impact on outcomes in patients with oesophago-gastric (OG) cancer. The primary aim of this study was to establish the feasibility of delivering a digital prehabilitation service. METHODS: Patients undergoing treatment for OG cancer with curative intent were recruited into the study. During the COVID-19 pandemic, patients were offered a digital prehabilitation service. Following the lifting of COVID-19 restrictions, patients were also offered both a hybrid clinic-based in-person service and a digital service. Implementation and clinical metrics from the two prehabilitation models were compared. RESULTS: 31 of 41 patients accepted the digital service (75%). Of the people who started the digital programme, 3 dropped out (10%). Compliance with the weekly touchpoints was 86%, and the median length of programme was 12 weeks. Twenty-six patients enrolled in the in-person service. Two patients dropped out (10%). Average compliance to weekly touchpoints was 71%, and the median length of programme was 10 weeks. In the digital group, sit to stand (STS) increased from 14.5 (IQR 10.5-15.5) to 16 (IQR 16-22); p = 0.02. Median heart rate recovery (HRR) increased from 10.5 (IQR 7.5-14) to 15.5 (IQR 11-20) bpm; p = 0.24. There was a significant drop in distress (median 3 (IQR 0-5) to 1 (IQR 0-2); p = 0.04) and a small drop in anxiety (median 3 (0-5) to 2 (0-3); p = 0.22). There was no difference in the postoperative complication rate and length of hospital stay between the two groups. DISCUSSION: This study has shown that digital prehabilitation can be delivered effectively to patients with OG cancer, with high engagement and retention rates. We observed improvements in some physical and psychological parameters with the digital service, with comparable clinical outcomes to the in-person service.


Assuntos
COVID-19 , Neoplasias Gástricas , Humanos , Exercício Pré-Operatório , Estudos de Viabilidade , Pandemias , Cuidados Pré-Operatórios
7.
Cancer Epidemiol Biomarkers Prev ; 31(12): 2095-2105, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36215181

RESUMO

There is an urgent need for cost-effective, non-invasive tools to detect early stages of gastrointestinal cancer (colorectal, gastric, and esophageal cancers). Despite many publications suggesting circulating metabolites acting as accurate cancer biomarkers, few have reached the clinic. In upper gastrointestinal cancer this is critically important, as there is no test to complement gold-standard endoscopic evaluation in patients with mild symptoms that do not meet referral criteria. Therefore, this study aimed to describe and solve this translational gap. Studies reporting diagnostic accuracy of metabolomic blood-based gastrointestinal cancer biomarkers from 2007 to 2020 were systematically reviewed and progress of each biomarker along the discovery-validation-adoption pathway was mapped. Successful biomarker translation was defined as a composite endpoint, including patent protection/FDA approval/recommendation in national guidelines. The review found 77 biomarker panels of gastrointestinal cancer, including 25 with an AUROC >0.9. All but one was stalled at the discovery phase, 9.09% were patented and none were clinically approved, confirming the extent of biomarker translational gap. In addition, there were numerous "re-discoveries," including histidine, discovered in 7 colorectal studies. Finally, this study quantitatively supports the presence of a translational gap between discovery and clinical adoption, despite clear evidence of highly performing biomarkers with significant potential clinical value.


Assuntos
Neoplasias Colorretais , Neoplasias Gastrointestinais , Humanos , Neoplasias Gastrointestinais/diagnóstico , Metabolômica , Biomarcadores Tumorais , Testes Hematológicos
8.
JAMA Surg ; 157(11): e223899, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36069888

RESUMO

Importance: Cancers of the upper gastrointestinal tract remain a major contributor to the global cancer burden. The accurate mapping of tumor margins is of particular importance for curative cancer resection and improvement in overall survival. Current mapping techniques preclude a full resection margin assessment in real time. Objective: To evaluate whether diffuse reflectance spectroscopy (DRS) on gastric and esophageal cancer specimens can differentiate tissue types and provide real-time feedback to the operator. Design, Setting, and Participants: This was a prospective ex vivo validation study. Patients undergoing esophageal or gastric cancer resection were prospectively recruited into the study between July 2020 and July 2021 at Hammersmith Hospital in London, United Kingdom. Tissue specimens were included for patients undergoing elective surgery for either esophageal carcinoma (adenocarcinoma or squamous cell carcinoma) or gastric adenocarcinoma. Exposures: A handheld DRS probe and tracking system was used on freshly resected ex vivo tissue to obtain spectral data. Binary classification, following histopathological validation, was performed using 4 supervised machine learning classifiers. Main Outcomes and Measures: Data were divided into training and testing sets using a stratified 5-fold cross-validation method. Machine learning classifiers were evaluated in terms of sensitivity, specificity, overall accuracy, and the area under the curve. Results: Of 34 included patients, 22 (65%) were male, and the median (range) age was 68 (35-89) years. A total of 14 097 mean spectra for normal and cancerous tissue were collected. For normal vs cancer tissue, the machine learning classifier achieved a mean (SD) overall diagnostic accuracy of 93.86% (0.66) for stomach tissue and 96.22% (0.50) for esophageal tissue and achieved a mean (SD) sensitivity and specificity of 91.31% (1.5) and 95.13% (0.8), respectively, for stomach tissue and of 94.60% (0.9) and 97.28% (0.6) for esophagus tissue. Real-time tissue tracking and classification was achieved and presented live on screen. Conclusions and Relevance: This study provides ex vivo validation of the DRS technology for real-time differentiation of gastric and esophageal cancer from healthy tissue using machine learning with high accuracy. As such, it is a step toward the development of a real-time in vivo tumor mapping tool for esophageal and gastric cancers that can aid decision-making of resection margins intraoperatively.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Trato Gastrointestinal Superior , Humanos , Masculino , Idoso , Idoso de 80 Anos ou mais , Feminino , Margens de Excisão , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/cirurgia , Estudos Prospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirurgia , Análise Espectral/métodos , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Trato Gastrointestinal Superior/patologia
10.
BMJ Open ; 12(6): e057847, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672065

RESUMO

OBJECTIVES: To identify factors that influenced women who chose to leave academic medicine. DESIGN AND MAIN OUTCOME MEASURES: Independent consultants led a focus group of women in medicine who had left academia after completion of their postgraduate research degree at Imperial College London Faculty of Medicine. Thematic analysis was performed on the transcribed conversations. PARTICIPANTS AND SETTING: Nine women physicians who completed a postgraduate degree (MD or PhD) at a large London Medical School and Academic Health Sciences Centre, Imperial College London, but did not go on to pursue a career in academic medicine. RESULTS: Influences to leave clinical academia were summarised under eight themes-career intentions, supervisor support, institutional human resources support, inclusivity, work-life balance, expectations, mentors and role models, and pregnancy and maternity leave. CONCLUSION: The women in our focus group reported several factors contributing to their decision to leave clinical academia, which included lack of mentoring tailored to specific needs, low levels of acceptance for flexible working to help meet parental responsibilities and perceived explicit gender biases. We summarise the multiple targeted strategies that Imperial College London has implemented to promote retention of women in academic medicine, although more research needs to be done to ascertain the most effective interventions.


Assuntos
Medicina , Faculdades de Medicina , Centros Médicos Acadêmicos , Docentes de Medicina , Feminino , Humanos , Londres , Masculino , Mentores , Gravidez , Pesquisa Qualitativa
11.
Br J Surg ; 109(5): 418-425, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35233634

RESUMO

BACKGROUND: Oesophageal adenocarcinoma poses a significant global health burden, yet the staging used to predict survival has limited ability to stratify patients by outcome. This study aimed to identify published clinical models that predict survival in oesophageal adenocarcinoma and to evaluate them using an independent international multicentre dataset. METHODS: A systematic literature search (title and abstract) using the Ovid Embase and MEDLINE databases (from 1947 to 11 July 2020) was performed. Inclusion criteria were studies that developed or validated a clinical prognostication model to predict either overall or disease-specific survival in patients with oesophageal adenocarcinoma undergoing surgical treatment with curative intent. Published models were validated using an independent dataset of 2450 patients who underwent oesophagectomy for oesophageal adenocarcinoma with curative intent. RESULTS: Seventeen articles were eligible for inclusion in the study. Eleven models were suitable for testing in the independent validation dataset and nine of these were able to stratify patients successfully into groups with significantly different survival outcomes. Area under the receiver operating characteristic curves for individual survival prediction models ranged from 0.658 to 0.705, suggesting poor-to-fair accuracy. CONCLUSION: This study highlights the need to concentrate on robust methodologies and improved, independent, validation, to increase the likelihood of clinical adoption of survival predictions models.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Bases de Dados Factuais , Esofagectomia/métodos , Humanos , Prognóstico
12.
Dis Esophagus ; 35(11)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35138383

RESUMO

Preoperative cardiopulmonary exercise testing (CPET) provides an objective assessment of aerobic fitness in patients undergoing surgery. While peak oxygen uptake during exercise (VO2peak) and anaerobic threshold have demonstrated a moderate correlation with the development of complications following esophagectomy, no clinically useful threshold values have been defined. By pooling patient level data from existing studies, we aimed to define optimal thresholds for preoperative CPET parameters to predict patients at high risk of postoperative complications. Studies reporting on the relationship between preoperative CPET variables and post-esophagectomy complications were determined from a comprehensive literature search. Patient-level data were obtained from six contributing centers for pooled-analyses. Outcomes of interest included cardiopulmonary and non-cardiopulmonary complications, unplanned intensive care unit readmission, and 90-day and 12-month all-cause mortality. Receiver operating characteristic curves and logistic regression models estimated the predictive value of CPET parameters for each individual outcome of interest. This analysis comprised of 621 patients who underwent CPET prior to esophagectomy during the period from January 2004 to March 2017. For both anaerobic threshold and VO2peak, none of the receiver operating characteristic curves achieved an area under the curve value > 0.66 for the outcomes of interest. The discriminatory ability of CPET for determining high-risk patients was found to be poor in patients undergoing an esophagectomy. CPET may only carry an adjunct role to clinical decision-making.


Assuntos
Esofagectomia , Teste de Esforço , Humanos , Esofagectomia/efeitos adversos , Teste de Esforço/efeitos adversos , Limiar Anaeróbio , Curva ROC , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Consumo de Oxigênio
13.
J Biomed Opt ; 27(2)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35106980

RESUMO

SIGNIFICANCE: Diffuse reflectance spectroscopy (DRS) allows discrimination of tissue type. Its application is limited by the inability to mark the scanned tissue and the lack of real-time measurements. AIM: This study aimed to develop a real-time tracking system to enable localization of a DRS probe to aid the classification of tumor and non-tumor tissue. APPROACH: A green-colored marker attached to the DRS probe was detected using hue-saturation-value (HSV) segmentation. A live, augmented view of tracked optical biopsy sites was recorded in real time. Supervised classifiers were evaluated in terms of sensitivity, specificity, and overall accuracy. A developed software was used for data collection, processing, and statistical analysis. RESULTS: The measured root mean square error (RMSE) of DRS probe tip tracking was 1.18 ± 0.58 mm and 1.05 ± 0.28 mm for the x and y dimensions, respectively. The diagnostic accuracy of the system to classify tumor and non-tumor tissue in real time was 94% for stomach and 96% for the esophagus. CONCLUSIONS: We have successfully developed a real-time tracking and classification system for a DRS probe. When used on stomach and esophageal tissue for tumor detection, the accuracy derived demonstrates the strength and clinical value of the technique to aid margin assessment in cancer resection surgery.


Assuntos
Neoplasias Gastrointestinais , Margens de Excisão , Sistemas Computacionais , Neoplasias Gastrointestinais/diagnóstico por imagem , Neoplasias Gastrointestinais/cirurgia , Humanos , Análise Espectral
14.
J Appl Phys ; 125(24)2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34421126

RESUMO

A zero-dimensional kinetics simulation of femtosecond laser ionization in nitrogen is proposed that includes fast gas heating effects, electron scattering (elastic and inelastic) rate coefficients from BOLSIG+ and photoionization based on filamentation theory. Key rate coefficients possessing significant uncertainty are tuned (within the range of variation found in literature) to reproduce the time-varying signal acquired by a bandpass-filtered photomultiplier tube with good agreement up to several hundred nanoseconds. Separate spectral measurements calibrate the relative strength of signal components. Derived equations relate the model to experimental measurements in absolute units. Reactions contributing to the rate of change of important species are displayed in terms of absolute rate and relative fraction. In general, decreasing the gas density lengthens the duration of early reactions and delays the start of later reactions. The model agrees with data taken in a variable temperature and pressure free jet by an intensified camera. Results demonstrate that initial signal depends primarily on gas density and secondarily on gas temperature. The optimal (maximum) initial signal occurs at a gas density below atmospheric. Decreases in gas density alter the evolution of excited-state populations, postponing the peak (while reducing its value) and slowing the rate of decay. For the optimal case, populations are favorably shifted in time with respect to the gate delay (and width) to boost the signal. Reductions in gas temperature generally enhance initial signal due to elevated dissociative recombination of cluster ions (along with excited-state coupling from quenching and energy pooling).

15.
BMJ Case Rep ; 20182018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30115720

RESUMO

A 27-year-old man presented to a major trauma centre with two posterolateral thoracic stab injuries over the right scapula and thoracoabdominal junction. He was tachycardic and hypotensive with a chest X-ray revealing a large right-sided tension haemothorax, requiring insertion of two intercostal chest drains. A subsequent CT scan demonstrated a grade 4 right kidney laceration with active back bleeding from a renal artery branch, through a right diaphragmatic defect, into the pleural cavity. Embolisation of the feeding renal vessel controlled the bleeding and avoided the need for a nephrectomy. The patient required subsequent video-assisted thoracoscopic evacuation of the haemothorax and diaphragmatic repair, confirming that there was no associated lung or major vessel injury. A ureteric stent was ultimately inserted to manage a persistent urinary leak. This case highlights a rare cause for a common traumatic presentation and the need for a multidisciplinary approach in effective management of complex, multiorgan trauma.


Assuntos
Hemotórax/etiologia , Rim/lesões , Artéria Renal/lesões , Ferimentos Perfurantes/complicações , Adulto , Transfusão de Sangue , Drenagem , Embolização Terapêutica , Hemotórax/diagnóstico por imagem , Hemotórax/terapia , Humanos , Lacerações/complicações , Masculino , Traumatismos Torácicos/complicações , Traumatismos Torácicos/terapia , Tomografia Computadorizada por Raios X
16.
Oncotarget ; 9(26): 18518-18528, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29719622

RESUMO

BACKGROUND: The current TNM staging system for oesophageal adenocarcinoma (OAC) has limited ability to stratify patients and inform clinical management following neo-adjuvant chemotherapy and surgery. RESULTS: Functional genomic analysis of the gene expression data using Gene Set Enrichment Analysis (GSEA) identified GLUT1 as putative prognostic marker in OAC.In the discovery cohort GLUT1 positivity was observed in 114 patients (80.9%) and was associated with poor overall survival (HR 2.08, 95% CI 1.1-3.94; p=0.024) following multivariate analysis. A prognostic model incorporating GLUT1, CRM and nodal status stratified patients into good, intermediate and poor prognosis groups (p< 0.001) with a median overall survival of 16.6 months in the poorest group.In the validation set 182 patients (69.5%) were GLUT1 positive and the prognostic model separated patients treated with neo-adjuvant chemotherapy and surgery (p<0.001) and surgery alone (p<0.001) into three prognostic groups. PATIENTS AND METHODS: Transcriptional profiling of 60 formalin fixed paraffin-embedded (FFPE) biopsies was performed. GLUT1 immunohistochemical staining was assessed in a discovery cohort of 141 FFPE OAC samples treated with neo-adjuvant chemotherapy and surgery at the Northern Ireland Cancer Centre from 2004-2012. Validation was performed in 262 oesophageal adenocarcinomas collected at four OCCAMS consortium centres. The relationship between GLUT1 staining, T stage, N stage, lymphovascular invasion and circumferential resection margin (CRM) status was assessed and a prognostic model developed using Cox Proportional Hazards. CONCLUSIONS: GLUT1 staining combined with CRM and nodal status identifies a poor prognosis sub-group of OAC patients and is a novel prognostic marker following potentially curative surgical resection.

17.
Eur J Surg Oncol ; 44(5): 594-599, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29459017

RESUMO

INTRODUCTION: Esophageal and gastric cancer have a poor prognosis and surgical intervention is associated with considerable morbidity, highlighting the need for careful preoperative assessment. The Incremental Shuttle Walk Test (ISWT) and Cardiopulmonary exercise testing (CPET) can assess preoperative fitness. This study aims to investigate their correlation with both postoperative respiratory complications and overall survival. PATIENTS AND METHODS: Patients were identified who underwent esophageal or gastric resections for cancer between 2010 and 2014 and had ISWT and/or CPET assessments. Tumor differentiation, stage, postoperative respiratory complications, and outcome were documented and then correlated with the results of the preoperative fitness assessments. RESULTS: Neither the ISWT result, anaerobic threshold (AT) nor VO2 Max correlated well with perioperative complications. However, ISWT (p < 0.001), AT (p < 0.001) and VO2 Max (p < 0.001) all correlated strongly with overall survival. No patient with a score of less than 350 m on ISWT survived beyond 3 years. In a subset of patients with ISWT results both pre and post chemotherapy (n = 49), those that had an improvement in result had a 19% incidence of post-operative respiratory complications compared to 45% where the result did not change or declined, though due to small numbers this only approached significance (p = 0.08). CONCLUSION: ISWT and CPET can be useful preoperative tools to predict overall survival for patients undergoing esophago-gastric resection. Furthermore, patients that improve their functional status during chemotherapy seem to do better than those where it remains static or declines.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia , Teste de Esforço , Tolerância ao Exercício , Gastrectomia , Complicações Pós-Operatórias/epidemiologia , Doenças Respiratórias/epidemiologia , Neoplasias Gástricas/cirurgia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/patologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Teste de Caminhada
18.
Meas Sci Technol ; 29(11)2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33442201

RESUMO

Femtosecond laser electronic excitation tagging (FLEET) velocimetry is characterized for the first time at high-pressure, low-temperature conditions. FLEET signal intensity and signal lifetime data are examined for their thermodynamic dependences; temperatures range from 89 K to 275 K while pressures are varied from 85 kPa to 400 kPa. The FLEET signal intensity is found to scale linearly with the flow density. An inverse density dependence is observed in the FLEET signal lifetime data, with little independent sensitivity to the other thermodynamic conditions apparent. FLEET velocimetry is demonstrated in the NASA Langley 0.3-m Transonic Cryogenic Tunnel. Velocity measurements are made over the entire operational envelope: Mach numbers from 0.2 to 0.75, total (stagnation) temperatures from 100 K to 280 K, and total pressures from 100 kPa to 400 kPa. The velocity measurement accuracy is assessed over this domain of conditions. Measurement errors below 1.15 percent are typical, with slightly decreasing accuracy as temperatures are decreased. Assessment of the measurement precision finds a zero-velocity precision of 0.4 m/s. The precision is observed to have a weak temperature dependence as well, likely a result of the shorter lifetimes experienced at higher densities. The velocity dynamic range is found to have a nominal value of 650. Finally the spatial resolution of the measurements is found to be a dominated by the physical size of the FLEET signal and advective motion. The transverse spatial resolution is found to be 1 mm, while the streamwise spatial resolution is dependent on velocity with a minimum of 2 mm and a maximum of 3.3 mm.

19.
Gut ; 62(10): 1415-24, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22773546

RESUMO

OBJECTIVE: The success of personalised therapy depends on identification and inhibition of the oncogene(s) on which that tumour is dependent. We aimed to determine whether a receptor tyrosine kinase (RTK) array could be used to select the most effective therapeutic strategies in molecularly heterogeneous oesophago-gastric adenocarcinomas. DESIGN: Gene expression profiling from oesophago-gastric tumours (n=75) and preinvasive stages (n=57) identified the active signalling pathways, which was confirmed using immunohistochemistry (n=434). RTK arrays on a cell line panel (n=14) determined therapeutic targets for in vitro cytotoxic testing. Feasibility of this personalised approach was tested in tumour samples (n=46). RESULTS: MAPK was the most frequently activated pathway (32/75 samples (42.7%)) with progressive enrichment in preinvasive disease stages (p<0.05) and ERK phosphorylation in 148/434 (34.3%) independent samples. Cell lines displayed a range of RTK activation profiles. When no RTKs were activated, tyrosine kinase inhibitors (TKIs) and a Mek inhibitor were not useful (MKN1). In lines with a dominant phosphorylated RTK (OE19, MKN45 and KATOIII), selection of this TKI or Mek in nM concentrations induced cytotoxicity and inhibited Erk and Akt phosphorylation. In cells lines with complex activation profiles (HSC39 and OE33), a combination of TKIs or Mek inhibition (in nM concentrations) was necessary for cytotoxicity and inhibition of Erk and Akt phosphorylation. Human tumours demonstrated diverse activation profiles and 65% of cases had two or more active RTKs. CONCLUSIONS: The MAPK pathway is commonly activated in oesophago-gastric cancer following activation of a variety of RTKs. Molecular phenotyping can inform a rational choice of targeted therapy.


Assuntos
Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Esôfago de Barrett/tratamento farmacológico , Esôfago de Barrett/genética , Esôfago de Barrett/metabolismo , Esôfago de Barrett/patologia , Biomarcadores Tumorais/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Descoberta de Drogas/métodos , Ativação Enzimática/efeitos dos fármacos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Estudos de Viabilidade , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fosforilação/efeitos dos fármacos , Lesões Pré-Cancerosas/tratamento farmacológico , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Medicina de Precisão/métodos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
20.
Int J Surg Case Rep ; 2(8): 306-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22096761

RESUMO

Cysts of the adrenal gland are rare and are usually discovered incidentally. Large adrenal cysts can however present with severe abdominal pain and can be complicated by haemorrhage, rupture or infection. Adrenal pseudocysts appear to result from haemorrhage within a normal adrenal gland and can expand to accommodate massive amounts of fluid.We report the case of a 39-year-old woman who presented with worsening right upper quadrant pain. An ultrasound scan of the abdomen confirmed a large 29 cm × 20 cm × 17 cm cyst that appeared to originate in the upper pole of the right kidney causing displacement of the liver and right kidney.Following complete aspiration the cyst re-accumulated and an MRI scan demonstrated a thickened and irregular cyst wall with haemorrhagic fluid. Laparoscopic right adrenalectomy was performed and the histopathological diagnosis was confirmed as an adrenal pseudocyst.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA