Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
BMC Cancer ; 23(1): 896, 2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37741968

RESUMO

BACKGROUND: The dense stroma of pancreatic ductal adenocarcinomas is a major barrier to drug delivery. To increase the local drug diffusion gradient, high doses of chemotherapeutic agent doxorubicin can be released from thermally-sensitive liposomes (ThermoDox®) using ultrasound-mediated hyperthermia at the tumour target. PanDox is designed as a Phase 1 single centre study to investigate enhancing drug delivery to adult patients with non-operable pancreatic ductal adenocarcinomas. The study compares a single cycle of either conventional doxorubicin alone or ThermoDox® with focused ultrasound-induced hyperthermia for targeted drug release. METHODS: Adults with non-resectable pancreatic ductal adenocarcinoma are allocated to receive a single cycle of either doxorubicin alone (Arm A) or ThermoDox® with focused ultrasound-induced hyperthermia (Arm B), based on patient- and tumour-specific safety conditions. Participants in Arm B will undergo a general anaesthetic and pre-heating of the tumour by extra-corporal focused ultrasound (FUS). Rather than employing invasive thermometry, ultrasound parameters are derived from a patient-specific treatment planning model to reach the 41 °C target temperature for drug release. ThermoDox® is then concurrently infused with further ultrasound exposure. Tumour biopsies at the targeted site from all patients are analysed post-treatment using high performance liquid chromatography to quantify doxorubicin delivered to the tumour. The primary endpoint is defined as a statistically significant enhancement in concentration of total intra-tumoural doxorubicin, comparing samples from patients receiving liposomal drug with FUS to free drug alone. Participants are followed for 21 days post-treatment to assess secondary endpoints, including radiological assessment to measure changes in tumour activity by Positron Emission Tomography Response Criteria in Solid Tumours (PERCIST) criteria, adverse events and patient-reported symptoms. DISCUSSION: This early phase study builds on previous work targeting tumours in the liver to investigate whether enhancement of chemotherapy delivery using ultrasound-mediated hyperthermia can be translated to the stroma-dense environment of pancreatic ductal adenocarcinoma. If successful, it could herald a new approach towards managing these difficult-to-treat tumours. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04852367 . Registered 21st April 2022. EudraCT number: 2019-003950-10 (Registered 2019) Iras Project ID: 272253 (Registered 2019) Ethics Number: 20/EE/0284.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Policetídeos , Adulto , Humanos , Tomografia Computadorizada por Raios X , Doxorrubicina/uso terapêutico , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/tratamento farmacológico , Antraciclinas , Antibióticos Antineoplásicos/uso terapêutico , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Ensaios Clínicos Fase I como Assunto , Neoplasias Pancreáticas
2.
BJR Case Rep ; 9(1): 20220101, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36873231

RESUMO

Urogenital tuberculosis (UGTB) can affect the entire urinary tract including the kidneys, ureters (strictures), urinary bladder, prostate in addition to involving reproductive tracts. In modern day practice, both ultrasound and cross-sectional imaging play an important role in the radiological diagnosis of UGTB. The sequalae of untreated UGTB is morbid and can lead to end-stage renal failure, infertility, and life-threatening systemic infection. UGTB is less commonly observed in developed countries and may mimic other pathologies including malignancy. Thus, it is important that radiologists consider the differential diagnosis early, particularly individuals with risk factors such as travel to endemic regions, to allow optimal treatment and ensure best prognostic outcomes. UGTB can typically be managed by Infectious Disease clinicians with multidrug chemotherapy. We have presented a case of microbiologically proven extrapulmonary tuberculosis (TB) predominantly involving the genitourinary tract. The response to TB agents and lack of evidence of co-infection with another organism, might suggest this as the first published case of emphysematous tuberculous prostatitis. Emphysematous prostatitis is indicative of a gas-forming infection of the prostate, and is associated with abscess formation in the vast majority of case and is an easily identified radiological feature on CT. It is not a well-recognised feature of Mycobacterium tuberculosis infection and thus microbiological diagnosis should be sought to confirm the diagnosis.

3.
Br J Radiol ; 96(1147): 20220565, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36752570

RESUMO

The limitation of the function of antitumour immune cells is a common hallmark of cancers that enables their survival. As such, the potential of immune checkpoint inhibition (ICI) acts as a paradigm shift in the treatment of a range of cancers but has not yet been fully capitalised. Combining minimally and non-invasive locoregional therapies offered by radiologists with ICI is now an active field of research with the aim of furthering therapeutic capabilities in medical oncology. In parallel to this impending advancement, the "imaging toolbox" available to radiologists is also growing, enabling more refined tumour characterisation as well as greater accuracy in evaluating responses to therapy. Options range from metabolite labelling to cellular localisation to immune checkpoint screening. It is foreseeable that these novel imaging techniques will be integrated into personalised treatment algorithms. This growth in the field must include updating the current standardised imaging criteria to ensure they are fit for purpose. Such criteria is crucial to both appropriately guide clinical decision-making regarding next steps of treatment, but also provide reliable prognosis. Quantitative approaches to these novel imaging techniques are also already being investigated to further optimise personalised therapeutic decision-making. The therapeutic potential of specific ICIs and locoregional therapies could be determined before administration thus limiting unnecessary side-effects whilst maintaining efficacy. Several radiological aspects of oncological care are advancing simultaneously. Therefore, it is essential that each development is assessed for clinical use and optimised to ensure the best treatment decisions are being offered to the patient. In this review, we discuss state of the art advances in novel functional imaging techniques in the field of immuno-oncology both pre-clinically and clinically.


Assuntos
Inibidores de Checkpoint Imunológico , Imunoterapia , Neoplasias , Inibidores de Checkpoint Imunológico/uso terapêutico , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Neoplasias/terapia , Radiologia
4.
ERJ Open Res ; 8(3)2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35795307

RESUMO

Background: Interstitial lung abnormalities (ILA) are specific spatial patterns on computed tomography (CT) scan potentially compatible with early interstitial lung disease. A proportion will progress; management involves risk stratification and surveillance. Elevated blood monocyte levels have been shown to associate with progression of idiopathic pulmonary fibrosis. The aims of the present study were: 1) to estimate the proportion of "early fibrotic" (EF)-ILAs (reticular±ground-glass opacities, excluding traction bronchiectasis and honeycombing) on CT scans of patients attending all-indications thoracic CTs, and proportion demonstrating radiological progression; and 2) to explore association between peripheral blood leukocyte levels and ILA progression. Methods: We analysed all thoracic CT reports in individuals aged 45-75 years performed between January 2015 and December 2020 in one large teaching hospital (Oxford, UK) to identify patient CT reports consistent with EF-ILA. CT-contemporaneous blood leukocyte counts were examined to explore contribution to progression and all-cause mortality, using multivariate Cox regression. Results: 40 711 patients underwent thoracic CT imaging during this period. 1259 (3.1%) demonstrated the EF-ILA pattern (mean±sd age 65.4±7.32 years; 735 (47.8%) male). EF-ILA was significantly associated with all-cause mortality (hazard ratio 1.87, 95% CI 1.25-2.78; p=0.002). 362 cases underwent at least one follow-on CT. Radiological progression was observed in 157 (43.4%) cases: increase in reticulation n=51, new traction bronchiectasis n=84, honeycombing n=22. Monocyte count, neutrophil count, monocyte:lymphocyte ratio, neutrophil:lymphocyte ratio and "systemic inflammatory response index" were significantly associated with radiological progression. Conclusion: 3.1% of subjects requiring thoracic CT during a 6-year period demonstrated EF-ILA. Monocyte levels and blood leukocyte-derived indexes were associated with radiological progression and could indicate which patients may require closer follow-up.

5.
Expert Opin Drug Deliv ; 19(8): 899-912, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35830722

RESUMO

INTRODUCTION: Many small molecules and biologic therapeutics have been developed for solid tumor therapy. However, the unique physiology of tumors makes the actual delivery of these drugs into the tumor mass inefficient. Such delivery requires transport from blood vessels, across the vasculature and into and through interstitial space within a tumor. This transportation is dependent on the physiochemical properties of the therapeutic agent and the biological properties of the tumor. It was hoped the application of nanoscale drug carrier systems would solve this problem. However, issues with poor tumor accumulation and limited drug release have impeded clinical impact. In response, these carrier systems have been redesigned to be paired with targetable external mechanical stimuli which can trigger much enhanced drug release and deposition. AREAS COVERED: The pre-clinical and clinical progress of thermolabile drug carrier systems and the modalities used to trigger the release of their cargo are assessed. EXPERT OPINION: Combined application of mild hyperthermia and heat-responsive liposomal drug carriers has great potential utility. Clinical trials continue to progress this approach and serve to refine the technologies, dosing regimens and exposure parameters that will provide optimal patient benefit.


Assuntos
Antineoplásicos , Hipertermia Induzida , Neoplasias , Doxorrubicina , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Lipossomos/química , Neoplasias/tratamento farmacológico
6.
Sci Rep ; 11(1): 4404, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33623089

RESUMO

Triggered release and targeted drug delivery of potent anti-cancer agents using hyperthermia-mediated focused-ultrasound (FUS) is gaining momentum in the clinical setting. In early phase studies, tissue biopsy samples may be harvested to assess drug delivery efficacy and demonstrate lack of instantaneous cell death due to FUS exposure. We present an optimised tissue cell recovery method and a cell viability assay, compatible with intra-cellular doxorubicin. Flow cytometry was used to determine levels of cell death with suspensions comprised of: (i) HT29 cell line exposed to hyperthermia (30 min at 47 °C) and/or doxorubicin, or ex-vivo bovine liver tissue exposed to (ii) hyperthermia (up to 2 h at 45 °C), or (iii) ablative high intensity FUS (HIFU). Flow cytometric analysis revealed maximal cell death in HT29 receiving both heat and doxorubicin insults and increases in both cell granularity (p < 0.01) and cell death (p < 0.01) in cells recovered from ex-vivo liver tissue exposed to hyperthermia and high pressures of HIFU (8.2 MPa peak-to-peak free-field at 1 MHz) relative to controls. Ex-vivo results were validated with microscopy using pan-cytokeratin stain. This rapid, sensitive and highly quantitative cell-viability method is applicable to the small masses of liver tissue typically recovered from a standard core biopsy (5-20 mg) and may be applied to tissues of other histological origins including immunostaining.


Assuntos
Antineoplásicos/toxicidade , Apoptose , Doxorrubicina/toxicidade , Tratamento por Ondas de Choque Extracorpóreas/efeitos adversos , Citometria de Fluxo/métodos , Animais , Bovinos , Células Cultivadas , Células HT29 , Hepatócitos/efeitos dos fármacos , Hepatócitos/efeitos da radiação , Temperatura Alta/efeitos adversos , Humanos , Camundongos
7.
Ultrasound Med Biol ; 47(4): 982-997, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33451816

RESUMO

Lyso-thermosensitive liposomes (LTSLs) are specifically designed to release chemotherapy agents under conditions of mild hyperthermia. Preclinical studies have indicated that magnetic resonance (MR)-guided focused ultrasound (FUS) systems can generate well-controlled volumetric hyperthermia using real-time thermometry. However, high-throughput clinical translation of these approaches for drug delivery is challenging, not least because of the significant cost overhead of MR guidance and the much larger volumes that need to be heated clinically. Using an ultrasound-guided extracorporeal clinical FUS device (Chongqing HAIFU, JC200) with thermistors in a non-perfused ex vivo bovine liver tissue model with ribs, we present an optimised strategy for rapidly inducing (5-15 min) and sustaining (>30 min) mild hyperthermia (ΔT <+4°C) in large tissue volumes (≤92 cm3). We describe successful clinical translation in a first-in-human clinical trial of targeted drug delivery of LTSLs (TARDOX: a phase I study to investigate drug release from thermosensitive liposomes in liver tumours), in which targeted tumour hyperthermia resulted in localised chemo-ablation. The heating strategy is potentially applicable to other indications and ultrasound-guided FUS devices.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antibióticos Antineoplásicos/administração & dosagem , Neoplasias Colorretais/patologia , Sistemas de Liberação de Medicamentos , Hipertermia Induzida/instrumentação , Neoplasias Hepáticas/tratamento farmacológico , Ultrassonografia/instrumentação , Adenocarcinoma/secundário , Animais , Bovinos , Análise Custo-Benefício , Sistemas de Liberação de Medicamentos/efeitos adversos , Humanos , Hipertermia Induzida/efeitos adversos , Hipertermia Induzida/métodos , Lipossomos , Fígado , Neoplasias Hepáticas/secundário , Costelas , Temperatura , Ultrassonografia de Intervenção
8.
Ultraschall Med ; 41(5): 550-556, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31238385

RESUMO

OBJECTIVE: To evaluate the middle-term efficacy and complications of ultrasound-guided high intensity focused ultrasound (USgHIFU) for the treatment of symptomatic uterine fibroids in an NHS population. METHODS: A prospective observational single-center study at a single university hospital in Oxford, UK. Patients with symptomatic uterine fibroids who declined standard surgical/radiological intervention and were referred to the HIFU unit were considered for USgHIFU treatment. Clinical evaluation, adverse event monitoring, uterine fibroid symptoms and health-related quality of life questionnaire (UFS-QOL) and contrast-enhanced pelvic magnetic resonance imaging (MRI) were performed before and at regular intervals after treatment to assess patient outcome. RESULTS: 12 of 22 referred patients underwent one session of USgHIFU ablation of 14 fibroids overall and received a two-year follow-up. No serious adverse events were reported, but a second-degree skin burn was observed in one patient who had a surgical scar from a previous caesarean section. Mean symptom severity scores (SSS-QOL) improved significantly from 56.5 ±â€Š29.1 (SD) at baseline to 33.4 ±â€Š23.3 (p < 0.01) at three months, 45.0 ±â€Š35.4 (p < 0.05) at one year and 40.6 ± 32.7 (p < 0.01) at two years post-treatment. The mean non-perfused volume ratio was 67.7 ±â€Š39.0 % (SD) in the treated fibroids (n = 14) within three months of treatment. The mean volume reduction rates of the treated fibroids were 23.3 ± 25.5 % (SD) at 3 months post-treatment (p < 0.01, n = 14), 49.3 ± 23.7 % at 12 months (p < 0.05, n = 8), and 51.9 ±â€Š11.1 % at 24 months (p < 0.005, n = 8). CONCLUSION: This study demonstrates the clinical efficacy of USgHIFU ablation of uterine fibroids and the low risk of complications. We believe that this noninvasive approach may offer an alternative therapy for women with symptomatic uterine fibroids. While HIFU is fast becoming the standard of care for fibroid ablation in other countries, to our knowledge, this study is the first to present clinical experience of US-guided HIFU ablation of symptomatic uterine fibroids in an NHS population. PLAIN LANGUAGE SUMMARY: High intensity focused ultrasound (HIFU) can be used for the noninvasive ablation of symptomatic uterine fibroids, and MR-guided treatment has already gained FDA approval. Ultrasound-guided HIFU has the advantage of offering practicalities in anesthesia and considerable cost-savings over MR-guided treatments. In this prospective study we have demonstrated the middle-term efficacy and favorable safety profile of ultrasound-guided HIFU for the treatment of symptomatic uterine fibroids for the first time in an NHS population.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma , Neoplasias Uterinas , Cesárea , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Leiomioma/terapia , Imageamento por Ressonância Magnética , Gravidez , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento , Ultrassonografia de Intervenção , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/terapia
9.
Radiol Case Rep ; 14(10): 1197-1201, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31428215

RESUMO

Chordoma is the most common malignant tumor of the sacrum and is associated with significant neurologic morbidity. Local recurrence is very common, and the long-term prognosis is poor. High-intensity focused ultrasound (HIFU) is a noninvasive and nonionising ablative therapy that has been successful in treating other tumor types and is being evaluated as a new therapy for sacral chordoma. Contrast-enhanced magnetic resonance imaging is typically used to evaluate tumor perfusion following HIFU; however, its utility is limited in poorly perfused tumors. Diffusion-weighted imaging (DWI) provides tissue contrast based on differences in the diffusion of extracellular water without using gadolinium-based contrast agents. We present novel DWI findings following a planned partial HIFU ablation of a large sacral chordoma which had recurred after radiotherapy. Following HIFU, the treated tumor volume demonstrated loss of restriction on DWI correlating with photopenia on positron emission tomography. This suggests successful ablation and tumor necrosis. This novel finding may provide guidance for sequence selection when evaluating HIFU therapy for sacral chordoma and other tumor types for which contrast-enhanced magnetic resonance imaging may have limited utility.

10.
Radiology ; 291(1): 232-238, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30644817

RESUMO

Purpose To demonstrate the feasibility and safety of using focused ultrasound planning models to determine the treatment parameters needed to deliver volumetric mild hyperthermia for targeted drug delivery without real-time thermometry. Materials and Methods This study was part of the Targeted Doxorubicin, or TARDOX, phase I prospective trial of focused ultrasound-mediated, hyperthermia-triggered drug delivery to solid liver tumors ( ClinicalTrials.gov identifier NCT02181075). Ten participants (age range, 49-68 years; average age, 60 years; four women) were treated from March 2015 to March 2017 by using a clinically approved focused ultrasound system to release doxorubicin from lyso-thermosensitive liposomes. Ultrasonic heating of target tumors (treated volume: 11-73 cm3 [mean ± standard deviation, 50 cm3 ± 26]) was monitored in six participants by using a minimally invasive temperature sensor; four participants were treated without real-time thermometry. For all participants, CT images were used with a patient-specific hyperthermia model to define focused ultrasound treatment plans. Feasibility was assessed by comparing model-prescribed focused ultrasound powers to those implemented for treatment. Safety was assessed by evaluating MR images and biopsy specimens for evidence of thermal ablation and monitoring adverse events. Results The mean difference between predicted and implemented treatment powers was -0.1 W ± 17.7 (n = 10). No evidence of focused ultrasound-related adverse effects, including thermal ablation, was found. Conclusion In this 10-participant study, the authors confirmed the feasibility of using focused ultrasound-mediated hyperthermia planning models to define treatment parameters that safely enabled targeted, noninvasive drug delivery to liver tumors while monitored with B-mode guidance and without real-time thermometry. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Dickey and Levi-Polyachenko in this issue.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Hipertermia Induzida/métodos , Neoplasias Hepáticas/terapia , Terapia por Ultrassom/métodos , Idoso , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Estudos de Viabilidade , Feminino , Humanos , Lipossomos , Masculino , Pessoa de Meia-Idade , Veículos Farmacêuticos , Estudos Prospectivos
11.
Radiol Case Rep ; 13(6): 1259-1266, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30258519

RESUMO

Liver metastasis from breast cancer is associated with poor prognosis and is a major cause of early morbidity and mortality. When liver resection is not feasible, minimally invasive directed therapies are considered to attempt to prolong survival. Selective internal radiation therapy (SIRT) with yttrium-90 microspheres is a liver-directed therapy that can improve local control of liver metastases from colorectal cancer. We present a case of a patient with a ductal breast adenocarcinoma, who developed liver and bone metastasis despite extensive treatment with systemic chemotherapies. Following SIRT to the liver, after an initial response, the patient ultimately progressed in the liver after 7 months. Liver tumor histology obtained 20 months after the SIRT intervention demonstrated the presence of the resin microspheres in situ. This case report demonstrates the long-term control that may be achieved with SIRT to treat liver metastases from breast cancer that is refractory to previous chemotherapies, and the presence of microspheres in situ long-term.

12.
Lancet Oncol ; 19(8): 1027-1039, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30001990

RESUMO

BACKGROUND: Previous preclinical research has shown that extracorporeal devices can be used to enhance the delivery and distribution of systemically administered anticancer drugs, resulting in increased intratumoural concentrations. We aimed to assess the safety and feasibility of targeted release and enhanced delivery of doxorubicin to solid tumours from thermosensitive liposomes triggered by mild hyperthermia, induced non-invasively by focused ultrasound. METHODS: We did an open-label, single-centre, phase 1 trial in a single UK hospital. Adult patients (aged ≥18 years) with unresectable and non-ablatable primary or secondary liver tumours of any histological subtype were considered for the study. Patients received a single intravenous infusion (50 mg/m2) of lyso-thermosensitive liposomal doxorubicin (LTLD), followed by extracorporeal focused ultrasound exposure of a single target liver tumour. The trial had two parts: in part I, patients had a real-time thermometry device implanted intratumourally, whereas patients in part II proceeded without thermometry and we used a patient-specific model to predict optimal exposure parameters. We assessed tumour biopsies obtained before and after focused ultrasound exposure for doxorubicin concentration and distribution. The primary endpoint was at least a doubling of total intratumoural doxorubicin concentration in at least half of the patients treated, on an intention-to-treat basis. This study is registered with ClinicalTrials.gov, number NCT02181075, and is now closed to recruitment. FINDINGS: Between March 13, 2015, and March 27, 2017, ten patients were enrolled in the study (six patients in part I and four in part II), and received a dose of LTLD followed by focused ultrasound exposure. The treatment resulted in an average increase of 3·7 times in intratumoural biopsy doxorubicin concentrations, from an estimate of 2·34 µg/g (SD 0·93) immediately after drug infusion to 8·56 µg/g (5·69) after focused ultrasound. Increases of two to ten times were observed in seven (70%) of ten patients, satisfying the primary endpoint. Serious adverse events registered were expected grade 4 transient neutropenia in five patients and prolonged hospital stay due to unexpected grade 1 confusion in one patient. Grade 3-4 adverse events recorded were neutropenia (grade 3 in one patient and grade 4 in five patients), and grade 3 anaemia in one patient. No treatment-related deaths occurred. INTERPRETATION: The combined treatment of LTLD and non-invasive focused ultrasound hyperthermia in this study seemed to be clinically feasible, safe, and able to enhance intratumoural drug delivery, providing targeted chemo-ablative response in human liver tumours that were refractory to standard chemotherapy. FUNDING: Oxford Biomedical Research Centre, National Institute for Health Research.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/análogos & derivados , Hipertermia Induzida , Neoplasias Hepáticas/tratamento farmacológico , Ultrassonografia , Idoso , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem
13.
J Ther Ultrasound ; 5: 28, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29118984

RESUMO

BACKGROUND: TARDOX is a Phase I single center study of ultrasound triggered targeted drug delivery in adult oncology patients with incurable liver tumours. This proof of concept study is designed to demonstrate the safety and feasibility of targeted drug release and enhanced delivery of doxorubicin from thermally sensitive liposomes (ThermoDox®) triggered by mild hyperthermia induced by focused ultrasound in liver tumours. A key feature of the study is the direct quantification of the doxorubicin concentration before and after ultrasound exposure from tumour biopsies, using high performance liquid chromatography (HPLC). METHODS/DESIGN: The study is conducted in two parts: Part 1 includes minimally-invasive thermometry via a thermistor or thermocouple implanted through the biopsy co-axial needle core, to confirm ultrasound-mediated hyperthermia, whilst Part 2 is carried out without invasive thermometry, to more closely mimic the ultimately intended clinical implementation of the technique. Whilst under a general anaesthetic, adult patients with incurable confirmed hepatic primary or secondary (metastatic) tumours receive a single cycle of ThermoDox®, immediately followed by ultrasound-mediated hyperthermia in a single target liver tumour. For each patient in Part 1, the HPLC-derived total doxorubicin concentration in the ultrasound-treated tumour is directly compared to the concentration before ultrasound exposure in that same tumour. For each patient in Part 2, as the tumour biopsy taken before ultrasound exposure is not available, the mean of those Part 1 tumour concentrations is used as the comparator. Success of the study requires at least a two-fold increase in the total intratumoural doxorubicin concentration, or final concentrations over 10 µg/g, in at least 50% of all patients receiving the drug, where tissue samples are evaluable by HPLC. Secondary outcome measures evaluate safety and feasibility of the intervention. Radiological response in the target tumour and control liver tumours are analysed as a tertiary outcome measure, in addition to plasma pharmacokinetics, fluorescence microscopy and immunohistochemistry of the biopsy samples. DISCUSSION: If this early phase study can demonstrate that ultrasound-mediated hyperthermia can effectively enhance the delivery and penetration of chemotherapy agents intratumorally, it could enable application of the technique to enhance therapeutic outcomes across a broad range of drug classes to treat solid tumours. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02181075, Edura-CT Identifier: 2014-000514-61.Ethics Number: 14/NE/0124.

14.
Br J Neurosurg ; 31(4): 446-451, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27936948

RESUMO

High-intensity focused ultrasound describes the use of high-intensity focused ultrasound (HIFU) to ablate tumours without requiring an incision or other invasive procedure. This technique has been trialled on a range of tumours including uterine fibroids, prostate, liver and renal cancer. We describe our experience of using HIFU to ablate sacral chordoma in four patients with advanced tumours. Patients were treated under general anaesthetic or sedation using an ultrasound-guided HIFU device. HIFU therapy was associated with a reduction in tumour volume over time in three patients for whom follow up scans were available. Tumour necrosis was reliably demonstrated in two of the three patients. We have established a national trial to assess if HIFU may improve long-term outcome from sacral chordoma, details are given.


Assuntos
Cordoma/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Região Sacrococcígea/cirurgia , Neoplasias da Coluna Vertebral/cirurgia , Adolescente , Anestesia Geral , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/efeitos adversos , Humanos , Lactente , Masculino , Necrose/etiologia , Equipe de Assistência ao Paciente , Complicações Pós-Operatórias/epidemiologia , Resultado do Tratamento
15.
Eur J Pediatr Surg ; 26(3): 227-31, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26079742

RESUMO

Objectives Improved survival in infants with esophageal atresia (EA) with a birth weight < 1,500 g or a major cardiac anomaly has been reported when compared with the original Spitz classification proposed in 1994. Aim We reviewed outcome data for infants born over the last decade in our institution to update previously reported survival statistics. Materials and Methods The records of all neonates (n = 200) with a diagnosis of EA managed in a single institution between 2001 and 2011 were reviewed and compared with data from the original Spitz study and the subsequent reported cohort from the same institution. Data were obtained on birth weight, presence of a major cardiac anomaly, and survival. Differences in survival were compared using the Yates-corrected chi-square test. Local ethical study approval was obtained. Results Infants born over the last decade had a comparable overall survival rate of 93% (186/200) versus 92.6% (174/188) in the previously reported cohort (1993-2004). We demonstrate an improved survival as compared to the Spitz cohort (87.6%, 326 /372, p = 0.06) and a statistically significant improvement in survival in Group II (p = 0.01). Within this group, 12/51 neonates had a birth weight < 1,500 g and 39/51 had major cardiac anomalies. Of interest, of the nine deaths in Group II, eight were in the subgroup with major cardiac anomalies. Conclusion The survival of neonates in Group II has significantly improved. Mortalities within this group were predominantly in the subgroup with major cardiac anomalies suggesting birth weight is of less significance than in previous years reflecting recent advances in neonatal care. We propose an updated prognostic classification that makes a distinction between cardiac and low-birth-weight infants.


Assuntos
Atresia Esofágica/mortalidade , Anormalidades Múltiplas , Peso ao Nascer , Causas de Morte , Distribuição de Qui-Quadrado , Atresia Esofágica/classificação , Atresia Esofágica/complicações , Feminino , Cardiopatias Congênitas/complicações , Humanos , Recém-Nascido , Masculino , Estudos Retrospectivos , Risco , Taxa de Sobrevida , Resultado do Tratamento , Reino Unido/epidemiologia
16.
Neuro Oncol ; 13(8): 866-79, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21798848

RESUMO

Central nervous system primitive neuroectodermal tumor (CNS PNET) and pineoblastoma are highly malignant embryonal brain tumors with poor prognoses. Current therapies are based on the treatment of pediatric medulloblastoma, even though these tumors are distinct at both the anatomical and molecular level. CNS PNET and pineoblastoma have a worse clinical outcome than medulloblastoma; thus, improved therapies based on an understanding of the underlying biology of CNS PNET and pineoblastoma are needed. To this end, we characterized the genomic alterations of 36 pediatric CNS PNETs and 8 pineoblastomas using Affymetrix single nucleotide polymorphism arrays. Overall, the majority of CNS PNETs contained a greater degree of genomic imbalance than pineoblastomas, with gain of 19p (8 [27.6%] of 29), 2p (7 [24.1%] of 29), and 1q (6 [20.7%] of 29) common events in primary CNS PNETs. Novel gene copy number alterations were identified and corroborated by Genomic Identification of Significant Targets In Cancer (GISTIC) analysis: gain of PCDHGA3, 5q31.3 in 62.1% of primary CNS PNETs and all primary pineoblastomas and FAM129A, 1q25 in 55.2% of primary CNS PNETs and 50% of primary pineoblastomas. Comparison of our GISTIC data with publically available data for medulloblastoma confirmed these CNS PNET-specific copy number alterations. With use of the collection of 5 primary and recurrent CNS PNET pairs, we found that gain of 2p21 was maintained at relapse in 80% of cases. Novel gene copy number losses included OR4C12, 11p11.12 in 48.2% of primary CNS PNETs and 50% of primary pineoblastomas. Loss of CDKN2A/B (9p21.3) was identified in 14% of primary CNS PNETs and was significantly associated with older age among children (P = .05). CADPS, 3p14.2 was lost in 27.6% of primary CNS PNETs and was associated with poor prognosis (P = .043). This genome-wide analysis revealed the marked molecular heterogeneity of CNS PNETs and enabled the identification of novel genes and clinical associations potentially involved in the pathogenesis of these tumors.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Genoma Humano , Recidiva Local de Neoplasia/genética , Tumores Neuroectodérmicos Primitivos/genética , Pinealoma/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Proteínas de Ligação ao Cálcio/genética , Criança , Pré-Escolar , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Lactente , Masculino , Recidiva Local de Neoplasia/metabolismo , Tumores Neuroectodérmicos Primitivos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Glândula Pineal/metabolismo , Glândula Pineal/patologia , Pinealoma/metabolismo , Reação em Cadeia da Polimerase , Proteínas de Transporte Vesicular/genética
17.
BMJ Case Rep ; 20112011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22675087

RESUMO

A 67-year-old morbidly obese female with a background of stage 4 chronic renal failure, ischaemic heart disease, congestive cardiac failure, atrial fibrillation and type 2 diabetes mellitus presented with sepsis and necrotic lesions of the proximal lower limbs. Initial histological findings were consistent with the clinical diagnosis of calciphylaxis and supportive treatment was commenced with addition of a phosphate binder and dietary restriction. Due to high anaesthetic risk, her wounds were managed with larva therapy in the first instance, however, ultimately surgical debridement was the required. Repeat histology from a further biopsy revealed necrosis secondary to numerous thrombi in the cutaneous vessels and a new diagnosis of purpura fulminans was made, likely secondary to her sepsis. Unfortunately, despite aggressive medical and surgical treatment measures, this patient died of multiple organ dysfunction following a prolonged admission.


Assuntos
Calciofilaxia/diagnóstico , Púrpura Fulminante/diagnóstico , Púrpura Fulminante/etiologia , Sepse/complicações , Idoso , Calciofilaxia/complicações , Diabetes Mellitus Tipo 2/complicações , Diagnóstico Diferencial , Evolução Fatal , Feminino , Humanos , Púrpura Fulminante/terapia , Insuficiência Renal Crônica/complicações
18.
Ann Neurol ; 66(6): 825-32, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20035510

RESUMO

OBJECTIVE: Case series with (11)C-PK11195 and positron emission tomography (PET) in stroke patients suggest that activated microglia may be detected in remote brain regions with fiber tract connections to the lesion site as an indicator of poststroke neuroinflammation. However, the specificity of these imaging findings remains to be demonstrated. METHODS: In a prospective controlled study, we measured microglia activity using (11)C-PK11195-PET along the pyramidal tract, as defined by diffusion tensor imaging, in 21 patients with first-time acute subcortical ischemia within 2 weeks of stroke. Uptake ratios (affected vs unaffected side) were determined for a set of standardized volumes of interest along the pyramidal tracts (PT). Uptake ratios from patients in whom the PT was affected were compared with those in whom the PT was not affected. Uptake ratios were related to motor deficit and lesion size according to correlation analyses. RESULTS: Increased uptake ratios were only found in patients in whom the PT was affected by stroke. In the affected hemisphere, uptake was increased at the level of pons, midbrain, and internal capsule, but not in the oval center. The extent of remote microglia activation was independent of infarct size or clinical measures of stroke severity. INTERPRETATION: A specific activation of microglia was only found in patients in whom the PT was affected by the stroke and only caudal (anterograde) to the lesion; no activation was found in the retrograde direction or in those patients in whom the PT was not affected. These findings were independent of infarct size and may represent changes secondary to early Wallerian degeneration.


Assuntos
Córtex Cerebral/patologia , Microglia/patologia , Tratos Piramidais/patologia , Acidente Vascular Cerebral/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico , Isótopos de Carbono/metabolismo , Córtex Cerebral/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Isoquinolinas/metabolismo , Masculino , Microglia/diagnóstico por imagem , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Tratos Piramidais/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem
19.
Appl Opt ; 44(14): 2857-62, 2005 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-15943339

RESUMO

For three decades airborne laser-induced fluorescence has demonstrated value for chlorophyll biomass retrieval in wide-area oceanic field experiments, satellite validation, and algorithm development. A new chlorophyll biomass retrieval theory is developed using laser-induced and water Raman normalized fluorescence of both (a) chlorophyll and (b) chromophoric dissolved organic matter (CDOM). This airborne lidar retrieval theory is then independently confirmed by chlorophyll biomass obtained from concurrent (1) ship-cruise retrievals, (2) satellite inherent optical property (IOP) biomass retrievals, and (3) satellite standard band-ratio chlorophyll biomass retrievals. The new airborne lidar chlorophyll and CDOM fluorescence-based chlorophyll biomass retrieval is found to be more robust than prior lidar methods that used chlorophyll fluorescence only. Future research is recommended to further explain the underlying influence of CDOM on chlorophyll production.


Assuntos
Clorofila/análise , Monitoramento Ambiental/métodos , Fitoplâncton/isolamento & purificação , Fitoplâncton/metabolismo , Espectrometria de Fluorescência/métodos , Microbiologia da Água , Água/análise , Algoritmos , Biomassa , Medições Luminescentes/métodos , Oceanos e Mares , Compostos Orgânicos/análise , Astronave , Poluição da Água/análise
20.
Appl Opt ; 43(31): 5886-92, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15540447

RESUMO

In the upper layer of the global ocean, 2082 in situ chlorophyll biomass values (Chl) are retrieved by concurrent satellite-derived inherent optical properties (IOP). It is found that (1) the phytoplankton absorption coefficient IOP alone does not provide satisfactory (Chl) retrieval; (2) the chromophoric dissolved organic matter (CDOM) absorption coefficient IOP must also be used to obtain satisfactory retrieval through (Chl) alpha a ph + pa CDOM where p is a constant and a ph and aCDOM are, respectively, the phytoplankton and CDOM absorption coefficients; (3) the IOP-based (Chl) retrieval performance is comparable to standard satellite reflectance ratio retrievals (that have CDOM absorption intrinsically embedded within them); (4) inclusion of the total backscattering coefficient IOP does not contribute significantly to (Chl) retrieval; and (5) the new IOP-based algorithm may provide the possibility for future research to establish the actual role of extracellular CDOM from all sources in the intracellular production of chlorophyll biomass.


Assuntos
Algoritmos , Clorofila/análise , Monitoramento Ambiental/métodos , Fitoplâncton/metabolismo , Astronave , Análise Espectral/métodos , Poluição da Água/análise , Biomassa , Oceanos e Mares , Fitoplâncton/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Microbiologia da Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA