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1.
BMC Cancer ; 24(1): 813, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973009

RESUMO

BACKGROUND: Therapeutic options for early-stage hepatocellular carcinoma (HCC) in individual patients can be limited by tumor and location, liver dysfunction and comorbidities. Many patients with early-stage HCC do not receive curative-intent therapies. Stereotactic ablative body radiotherapy (SABR) has emerged as an effective, non-invasive HCC treatment option, however, randomized evidence for SABR in the first line setting is lacking. METHODS: Trans-Tasman Radiation Oncology Group (TROG) 21.07 SOCRATES-HCC is a phase II, prospective, randomised trial comparing SABR to other current standard of care therapies for patients with a solitary HCC ≤ 8 cm, ineligible for surgical resection or transplantation. The study is divided into 2 cohorts. Cohort 1 will compromise 118 patients with tumors ≤ 3 cm eligible for thermal ablation randomly assigned (1:1 ratio) to thermal ablation or SABR. Cohort 2 will comprise 100 patients with tumors > 3 cm up to 8 cm in size, or tumors ≤ 3 cm ineligible for thermal ablation, randomly assigned (1:1 ratio) to SABR or best other standard of care therapy including transarterial therapies. The primary objective is to determine whether SABR results in superior freedom from local progression (FFLP) at 2 years compared to thermal ablation in cohort 1 and compared to best standard of care therapy in cohort 2. Secondary endpoints include progression free survival, overall survival, adverse events, patient reported outcomes and health economic analyses. DISCUSSION: The SOCRATES-HCC study will provide the first randomized, multicentre evaluation of the efficacy, safety and cost effectiveness of SABR versus other standard of care therapies in the first line treatment of unresectable, early-stage HCC. It is a broad, multicentre collaboration between hepatology, interventional radiology and radiation oncology groups around Australia, coordinated by TROG Cancer Research. TRIAL REGISTRATION: anzctr.org.au, ACTRN12621001444875, registered 21 October 2021.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiocirurgia , Padrão de Cuidado , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/cirurgia , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/cirurgia , Radiocirurgia/métodos , Estudos Prospectivos , Masculino , Feminino , Estadiamento de Neoplasias , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Idoso , Adulto
2.
Nucleic Acids Res ; 49(15): 8796-8810, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34379778

RESUMO

During RNA elongation, the influenza A viral (IAV) RNA-dependent RNA polymerase (RdRp) residues in the active site interact with the triphosphate moiety of nucleoside triphosphate (NTP) for catalysis. The molecular mechanisms by which they control the rate and fidelity of NTP incorporation remain elusive. Here, we demonstrated through enzymology, virology and computational approaches that the R239 and K235 in the PB1 subunit of RdRp are critical to controlling the activity and fidelity of transcription. Contrary to common beliefs that high-fidelity RdRp variants exert a slower incorporation rate, we discovered a first-of-its-kind, single lysine-to-arginine mutation on K235 exhibited enhanced fidelity and activity compared with wild-type. In particular, we employed a single-turnover NTP incorporation assay for the first time on IAV RdRp to show that K235R mutant RdRp possessed a 1.9-fold increase in the transcription activity of the cognate NTP and a 4.6-fold increase in fidelity compared to wild-type. Our all-atom molecular dynamics simulations further elucidated that the higher activity is attributed to the shorter distance between K235R and the triphosphate moiety of NTP compared with wild-type. These results provide novel insights into NTP incorporation and fidelity control mechanisms, which lay the foundation for the rational design of IAV vaccine and antiviral targets.


Assuntos
Vírus da Influenza A/enzimologia , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/metabolismo , Transcrição Gênica , Proteínas Virais/química , Proteínas Virais/metabolismo , Substituição de Aminoácidos , Animais , Domínio Catalítico , Cães , Sequenciamento de Nucleotídeos em Larga Escala , Células Madin Darby de Rim Canino , Mutação , RNA Polimerase Dependente de RNA/genética , Alinhamento de Sequência , Proteínas Virais/genética
3.
Antimicrob Agents Chemother ; 65(8): e0029021, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34031051

RESUMO

Isavuconazole, administered as the water-soluble prodrug isavuconazonium sulfate, is a new triazole agent used to treat invasive fungal infections. This phase 1 study evaluated the pharmacokinetics (PK), safety, and tolerability of isavuconazole in 46 immunocompromised pediatric patients, stratified by age (1 to <6 [intravenous (i.v.) only], 6 to <12, and 12 to <18 years), receiving 10 mg/kg body weight (maximum, 372 mg) isavuconazonium sulfate either i.v. or orally. A population PK model using weight-based allometric scaling was constructed with the pediatric i.v. and oral data plus i.v. data from a phase 1 study in adults. The best model was a 3-compartment model with combined zero-order and first-order input, with linear elimination. Stepwise covariate modeling was performed in Perl-speaks-NONMEM version 4.7.0. None of the covariates examined, including age, sex, race, and body mass index, were statistically significant for any of the PK parameters. The area under the concentration-time curve at steady state (AUCSS) was predicted for pediatric patients using 1,000 Monte Carlo simulations per age cohort for each administration route. The probability of target attainment (AUCSS range, 60 to 233 µg · h/ml) was estimated; this target range was derived from plasma drug exposures in adults receiving the recommended clinical dose. Predicted plasma drug exposures were within the target range for >80% and >76% of simulated pediatric patients following i.v. or oral administration, respectively. Intravenous and oral administration of isavuconazonium sulfate at the studied dosage of 10 mg/kg was well tolerated and resulted in exposure in pediatric patients similar to that in adults. (This study has been registered at ClinicalTrials.gov under identifier NCT03241550).


Assuntos
Infecções Fúngicas Invasivas , Triazóis , Administração Oral , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Infecções Fúngicas Invasivas/tratamento farmacológico , Nitrilas/uso terapêutico , Piridinas/efeitos adversos , Triazóis/uso terapêutico
4.
BMC Cancer ; 21(1): 936, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34412605

RESUMO

BACKGROUND: Among patients with non-metastatic pancreatic cancer, 80% have high-risk, borderline resectable or locally advanced cancer, with a 5-year overall survival of 12%. MASTERPLAN evaluates the safety and activity of stereotactic body radiotherapy (SBRT) in addition to chemotherapy in these patients. METHODS AND DESIGN: MASTERPLAN is a multi-centre randomised phase II trial of 120 patients with histologically confirmed potentially operable pancreatic cancer (POPC) or inoperable pancreatic cancer (IPC). POPC includes patients with borderline resectable or high-risk tumours; IPC is defined as locally advanced or medically inoperable pancreatic cancer. Randomisation is 2:1 to chemotherapy + SBRT (investigational arm) or chemotherapy alone (control arm) by minimisation and stratified by patient cohort (POPC v IPC), planned induction chemotherapy and institution. Chemotherapy can have been commenced ≤28 days prior to randomisation. Both arms receive 6 × 2 weekly cycles of modified FOLFIRINOX (oxaliplatin (85 mg/m2 IV), irinotecan (150 mg/m2), 5-fluorouracil (2400 mg/m2 CIV), leucovorin (50 mg IV bolus)) plus SBRT in the investigational arm. Gemcitabine+nab-paclitaxel is permitted for patients unsuitable for mFOLFIRINOX. SBRT is 40Gy in five fractions with planning quality assurance to occur in real time. Following initial chemotherapy ± SBRT, resectability will be evaluated. For resected patients, adjuvant chemotherapy is six cycles of mFOLFIRINOX. Where gemcitabine+nab-paclitaxel was used initially, the adjuvant treatment is 12 weeks of gemcitabine and capecitabine or mFOLFIRINOX. Unresectable or medically inoperable patients with stable/responding disease will continue with a further six cycles of mFOLFIRINOX or three cycles of gemcitabine+nab-paclitaxel, whatever was used initially. The primary endpoint is 12-month locoregional control. Secondary endpoints are safety, surgical morbidity and mortality, radiological response rates, progression-free survival, pathological response rates, surgical resection rates, R0 resection rate, quality of life, deterioration-free survival and overall survival. Tertiary/correlative objectives are radiological measures of nutrition and sarcopenia, and serial tissue, blood and microbiome samples to be assessed for associations between clinical endpoints and potential predictive/prognostic biomarkers. Interim analysis will review rates of locoregional recurrence, distant failure and death after 40 patients complete 12 months follow-up. Fifteen Australian and New Zealand sites will recruit over a 4-year period, with minimum follow-up period of 12 months. DISCUSSION: MASTERPLAN evaluates SBRT in both resectable and unresectable patients with pancreatic ductal adenocarcinoma. TRIAL REGISTRATION: Australia New Zealand Clinical Trials Registry ACTRN12619000409178 , 13/03/2019. Protocol version: 2.0, 19 May 2019.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pancreáticas/terapia , Radiocirurgia/métodos , Adolescente , Adulto , Idoso , Ensaios Clínicos Fase II como Assunto , Terapia Combinada , Feminino , Fluoruracila/uso terapêutico , Seguimentos , Humanos , Irinotecano/uso terapêutico , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Oxaliplatina/uso terapêutico , Neoplasias Pancreáticas/patologia , Prognóstico , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
5.
BMC Cancer ; 21(1): 494, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33941111

RESUMO

BACKGROUND: Stereotactic Ablative Body Radiotherapy (SABR) is a non-invasive treatment which allows delivery of an ablative radiation dose with high accuracy and precision. SABR is an established treatment for both primary and secondary liver malignancies, and technological advances have improved its efficacy and safety. Respiratory motion management to reduce tumour motion and image guidance to achieve targeting accuracy are crucial elements of liver SABR. This phase II multi-institutional TROG 17.03 study, Liver Ablative Radiotherapy using Kilovoltage intrafraction monitoring (LARK), aims to investigate and assess the dosimetric impact of the KIM real-time image guidance technology. KIM utilises standard linear accelerator equipment and therefore has the potential to be a widely available real-time image guidance technology for liver SABR. METHODS: Forty-six patients with either hepatocellular carcinoma or oligometastatic disease to the liver suitable for and treated with SABR using Kilovoltage Intrafraction Monitoring (KIM) guidance will be included in the study. The dosimetric impact will be assessed by quantifying accumulated patient dose distribution with or without the KIM intervention. The patient treatment outcomes of local control, toxicity and quality of life will be measured. DISCUSSION: Liver SABR is a highly effective treatment, but precise dose delivery is challenging due to organ motion. Currently, there is a lack of widely available options for performing real-time tumour localisation to assist with accurate delivery of liver SABR. This study will provide an assessment of the impact of KIM as a potential solution for real-time image guidance in liver SABR. TRIAL REGISTRATION: This trial was registered on December 7th 2016 on ClinicalTrials.gov under the trial-ID NCT02984566 .


Assuntos
Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Movimentos dos Órgãos , Radiocirurgia/métodos , Radioterapia Guiada por Imagem/métodos , Austrália , Carcinoma Hepatocelular/secundário , Dinamarca , Marcadores Fiduciais , Humanos , Neoplasias Hepáticas/secundário , Qualidade de Vida , Radiocirurgia/efeitos adversos , Radiocirurgia/instrumentação , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Respiração , Resultado do Tratamento
6.
J Surg Oncol ; 123(1): 117-126, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33084061

RESUMO

BACKGROUND AND OBJECTIVES: Limited literature exists examining the immune microenvironment in liposarcoma, particularly with regard to the impact of radiotherapy. A major problem is the lack of scoring system for the tumour-infiltrating lymphocytes (TILs) in sarcoma. This study aims to describe the immune environment pre- and postradiotherapy and identify the optimal immune infiltrate scoring system for sarcoma. METHODS: Thirty-nine paired tissue samples (pre- and postradiotherapy) from patients with liposarcoma were scored by two pathologists for TILs using pre-existing systems (for breast cancer and melanoma) and compared for interobserver reliability. Immunohistochemical staining was performed for various immune markers. RESULTS: The TIL scoring system for breast cancer yielded perfect agreement (κ = 1.000). 21% of patients had increased TILs after radiotherapy, 87.5% of whom had dedifferentiated liposarcoma. Immune suppressor expression was increased frequently after radiotherapy (CD68 increased in 59.4%, PD-L1 increased in 25%). Immune effector expression (CD8) was unchanged in 84.4%. CONCLUSIONS: Breast cancer TIL scoring is reproducible in liposarcoma and has high interobserver reliability. Radiotherapy was observed to have a limited impact on immune effectors but seemed to have more impact in upregulating immune suppressors, suggesting radiotherapy may contribute to disease control through immunomodulatory effects. Dedifferentiated liposarcoma represents a uniquely responsive subtype.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Lipossarcoma/imunologia , Linfócitos do Interstício Tumoral/imunologia , Recidiva Local de Neoplasia/imunologia , Radioterapia/métodos , Microambiente Tumoral/imunologia , Adolescente , Adulto , Idoso , Linfócitos T CD8-Positivos/efeitos da radiação , Feminino , Seguimentos , Humanos , Lipossarcoma/patologia , Lipossarcoma/radioterapia , Linfócitos do Interstício Tumoral/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Prognóstico , Estudos Retrospectivos , Microambiente Tumoral/efeitos da radiação , Adulto Jovem
7.
Int J Colorectal Dis ; 33(4): 393-401, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29468354

RESUMO

PURPOSE: Radical management of locally recurrent rectal cancer (LRRC) can lead to prolonged survival. This study aims to assess outcomes and identify prognostic factors for patients with LRRC treated using a multimodality treatment protocol. METHODS: An analysis of a prospectively maintained institutional database of consecutive patients who underwent radical surgical resection for LRRC was performed. Potential prognostic factors were investigated using a Cox proportional hazards model. RESULTS: Ninety-eight patients were included in this study. A multimodality approach was taken in the majority, including preoperative chemoradiation (78%), intraoperative radiation therapy (47%) and adjuvant chemotherapy (41%). Extended resection was performed where required: bone resection (34%) and lateral pelvic sidewall dissection (31%). The rate of R0 resection was 66%. Estimated rates of 5-year overall survival (OS) and progression-free survival (PFS) were 41.8% (95% CI 32.5-53.7) and 22.5% (95% CI 15.3-33.1). On multivariate analysis, stage III disease at initial primary surgery, a positive margin at initial primary surgery, synchronous or previously resected oligometastases, a lateral or sacral invasive-type pelvic recurrence and the requirement for IORT all predicted for inferior PFS (p < 0.05). Eleven percent of patients subsequently underwent further pelvic surgery for pelvic re-recurrence and had an estimated 5-year OS rate of 54.5% (95% CI 29.0-100.0) from repeat surgery. CONCLUSIONS: Radical multimodality management of LRRC leads to prolonged survival in approximately 40% of patients. Those with sacral or lateral invasive-type recurrence or oligometastatic disease have inferior outcomes and further research is needed to optimise treatment for these groups.


Assuntos
Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia , Quimioterapia Adjuvante , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Resultado do Tratamento
8.
Acta Oncol ; 53(7): 909-16, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24456502

RESUMO

BACKGROUND: Chemoradiotherapy (CRT) for squamous cell carcinoma of the anus (SCCA) may cause significant toxicity, and concerns exist about its tolerability in the elderly. The authors compared tolerability and outcomes across the age groups following CRT for SCCA. METHODS: Single-institution retrospective analysis of patients with localized SCCA treated with CRT. CRT was standardized at 50.4-54 Gy, with concurrent infusional 5-fluorouracil and mitomycin C. Patients were arbitrarily categorized into three groups: Group 1 - age < 50 years; Group 2 - age ≥ 50 and < 70 years; and Group 3 - age ≥ 70 years. RESULTS: Of 284 patients identified, 278 were evaluable. The number of patients in each age group was: Group 1 - 51; Group 2 - 140; and Group 3 - 93. Baseline and treatment characteristics, tumor stage, rates of overall acute toxicity, need for unplanned treatment breaks and chemotherapy delivery were largely similar across the age groups. However, nine patients in Group 3 did not complete CRT, compared with five and none in Groups 1 and 2, respectively (p = 0.006). In addition, five patients in Group 3 had diarrhea requiring treatment break, compared with none in the other two groups (p = 0.004). At a median follow-up 5.3 years, there was no significant difference in overall survival (p = 0.11), disease-free survival (p = 0.22) or local-recurrence free survival (p = 0.34), across the three age groups. CONCLUSIONS: CRT is safe and tolerable in the elderly age group, and provides equivalent disease control rates compared with the younger age group. Age alone should therefore not preclude aggressive curative treatment.


Assuntos
Neoplasias do Ânus/terapia , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Ânus/mortalidade , Carcinoma de Células Escamosas/mortalidade , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mitomicina/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
9.
Radiother Oncol ; 194: 110185, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38412905

RESUMO

BACKGROUND: Locally advanced, bulky, unresectable sarcomas cause significant tumour mass effects, leading to burdensome symptoms. We have developed a novel Partially Ablative Body Radiotherapy (PABR) technique that delivers a high, ablative dose to the tumour core and a low, palliative dose to its periphery aiming to increase overall tumour response without significantly increasing treatment toxicity. AIM: This study aims to report the safety and oncologic outcomes of PABR in patients with bulky, unresectable sarcomas. METHODS AND MATERIALS: A total of 18 patients with histologically proven sarcoma treated with PABR from January 2020 to October 2023 were retrospectively reviewed. The primary endpoints were symptomatic and structural response rates. Secondary endpoints were overall survival, freedom from local progression, freedom from distant progression, and acute and late toxicity rates. RESULTS: All patients had tumours ≥5 cm with a median tumour volume of 985 cc, and the most common symptom was pain. The median age is 72.5 years and 44.5 % were ECOG 2-3. The most common regimen used was 20 Gy in 5 fractions with an intratumoral boost dose of 50 Gy (83.3 %). After a median follow-up of 11 months, 88.9 % of patients exhibited a partial response with a mean absolute tumour volume reduction of 49.5 %. All symptomatic patients experienced symptom improvement. One-year OS, FFLP and FFDP were 61 %, 83.3 % and 34.8 %, respectively. There were no grade 3 or higher toxicities. CONCLUSION: PABR for bulky, unresectable sarcomas appears to be safe and may provide good symptomatic response, tumour debulking, and local control. Further study is underway.


Assuntos
Cuidados Paliativos , Sarcoma , Humanos , Sarcoma/radioterapia , Sarcoma/patologia , Sarcoma/cirurgia , Sarcoma/mortalidade , Masculino , Cuidados Paliativos/métodos , Feminino , Idoso , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Carga Tumoral , Adulto , Dosagem Radioterapêutica
10.
Comput Med Imaging Graph ; 116: 102403, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38878632

RESUMO

BACKGROUND AND OBJECTIVES: Bio-medical image segmentation models typically attempt to predict one segmentation that resembles a ground-truth structure as closely as possible. However, as medical images are not perfect representations of anatomy, obtaining this ground truth is not possible. A surrogate commonly used is to have multiple expert observers define the same structure for a dataset. When multiple observers define the same structure on the same image there can be significant differences depending on the structure, image quality/modality and the region being defined. It is often desirable to estimate this type of aleatoric uncertainty in a segmentation model to help understand the region in which the true structure is likely to be positioned. Furthermore, obtaining these datasets is resource intensive so training such models using limited data may be required. With a small dataset size, differing patient anatomy is likely not well represented causing epistemic uncertainty which should also be estimated so it can be determined for which cases the model is effective or not. METHODS: We use a 3D probabilistic U-Net to train a model from which several segmentations can be sampled to estimate the range of uncertainty seen between multiple observers. To ensure that regions where observers disagree most are emphasised in model training, we expand the Generalised Evidence Lower Bound (ELBO) with a Constrained Optimisation (GECO) loss function with an additional contour loss term to give attention to this region. Ensemble and Monte-Carlo dropout (MCDO) uncertainty quantification methods are used during inference to estimate model confidence on an unseen case. We apply our methodology to two radiotherapy clinical trial datasets, a gastric cancer trial (TOPGEAR, TROG 08.08) and a post-prostatectomy prostate cancer trial (RAVES, TROG 08.03). Each dataset contains only 10 cases each for model development to segment the clinical target volume (CTV) which was defined by multiple observers on each case. An additional 50 cases are available as a hold-out dataset for each trial which had only one observer define the CTV structure on each case. Up to 50 samples were generated using the probabilistic model for each case in the hold-out dataset. To assess performance, each manually defined structure was matched to the closest matching sampled segmentation based on commonly used metrics. RESULTS: The TOPGEAR CTV model achieved a Dice Similarity Coefficient (DSC) and Surface DSC (sDSC) of 0.7 and 0.43 respectively with the RAVES model achieving 0.75 and 0.71 respectively. Segmentation quality across cases in the hold-out datasets was variable however both the ensemble and MCDO uncertainty estimation approaches were able to accurately estimate model confidence with a p-value < 0.001 for both TOPGEAR and RAVES when comparing the DSC using the Pearson correlation coefficient. CONCLUSIONS: We demonstrated that training auto-segmentation models which can estimate aleatoric and epistemic uncertainty using limited datasets is possible. Having the model estimate prediction confidence is important to understand for which unseen cases a model is likely to be useful.

11.
BMC Cancer ; 13: 381, 2013 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-23937668

RESUMO

BACKGROUND: The kidneys are a principal dose-limiting organ in radiotherapy for upper abdominal cancers. The current understanding of kidney radiation dose response is rudimentary. More precise dose-volume response models that allow direct correlation of delivered radiation dose with spatio-temporal changes in kidney function may improve radiotherapy treatment planning for upper-abdominal tumours. METHODS/DESIGN: The Radiotherapy of Abdomen with Precise Renal Assessment with SPECT/CT Imaging (RAPRASI) is an observational clinical research study with participating sites at Sir Charles Gairdner Hospital (SCGH) in Perth, Australia and the Peter MacCallum Cancer Centre (PMCC) in Melbourne, Australia. Eligible patients are those with upper gastrointestinal cancer, without metastatic disease, undergoing conformal radiotherapy that will involve incidental radiation to one or both kidneys. For each patient, total kidney function is being assessed before commencement of radiotherapy treatment and then at 4, 12, 26, 52 and 78 weeks after the first radiotherapy fraction, using two procedures: a Glomerular Filtration Rate (GFR) measurement using the 51Cr-ethylenediamine tetra-acetic acid (EDTA) clearance; and a regional kidney perfusion measurement assessing renal uptake of 99mTc-dimercaptosuccinic acid (DMSA), imaged with a Single Photon Emission Computed Tomography / Computed Tomography (SPECT/CT) system. The CT component of the SPECT/CT provides the anatomical reference of the kidney's position. The data is intended to reveal changes in regional kidney function over the study period after the radiotherapy. These SPECT/CT scans, co-registered with the radiotherapy treatment plan, will provide spatial correlation between the radiation dose and regional renal function as assessed by SPECT/CT. From this correlation, renal response patterns will likely be identified with the purpose of developing a predictive model. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12609000322235.


Assuntos
Neoplasias Abdominais/radioterapia , Adenocarcinoma/radioterapia , Neoplasias Gastrointestinais/radioterapia , Rim/fisiopatologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias Abdominais/patologia , Adenocarcinoma/patologia , Seguimentos , Neoplasias Gastrointestinais/patologia , Taxa de Filtração Glomerular , Humanos , Rim/efeitos da radiação , Testes de Função Renal , Nova Zelândia , Prognóstico , Estudos Prospectivos , Radioterapia Conformacional
12.
J Pediatr Hematol Oncol ; 35(7): 504-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23823111

RESUMO

BACKGROUND: Hyperglycemia during corticosteroid and asparaginase therapy for acute lymphoblastic leukemia is a significant side effect that is usually treated with insulin. Metformin is an oral antidiabetic biguanide that may cause metabolic acidosis and liver enzyme abnormalities of possible concern in patients receiving chemotherapy. PROCEDURE: We reviewed patients with acute lymphoblastic leukemia treated with corticosteroids and asparaginase who received metformin for control of hyperglycemia. RESULTS: Seventeen patients received metformin, including 4 who received insulin before starting metformin therapy. Twelve were treated during initial induction therapy and 5 during relapse reinduction. Corticosteroids included dexamethasone in 11, prednisone in 5, and megesterol in 1. Fifteen received pegasparaginase.Patients were treated with metformin for a median of 6 days (range, 2 to 46 d). Metformin was started at a median glucose level of 286 mg/dL (range, 112 to 499 mg/mL). The glucose level was controlled with metformin alone in 12 patients without the need for insulin. Four patients received insulin before or concomitantly with metformin. In 1 patient, metformin failed to control the glucose level, and insulin was administered.No significant toxicity from metformin was seen. Two patients had an elevated anion gap and creatinine level because of extreme hyperglycemia. One patient had mild elevation in total bilirubin and 5 patients had mild elevation in serum alanine aminotransferase levels. There were no episodes of hypoglycemia. CONCLUSIONS: Metformin is safe and effective for therapy-induced hyperglycemia. Initially, insulin may be required for significant hyperglycemia or metabolic abnormalities. We are unaware of any prior studies using metformin in this population.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Hiperglicemia/induzido quimicamente , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Masculino , Metformina/administração & dosagem , Metformina/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Resultado do Tratamento
13.
Virus Res ; 323: 198991, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36302472

RESUMO

Rapid antigenic evolution of the influenza A virus surface antigen hemagglutinin undermines protection conferred by seasonal vaccines. Protective correlates targeted by universal vaccines such as cytotoxic T cells or HA stem directed broadly neutralizing antibodies have been shown to select for immune escape mutants during infection. We developed an in vivo serial passage mouse model for viral adaptation and used next generation sequencing to evaluate full genome viral evolution in the context of broadly protective immunity. Heterosubtypic immune pressure increased the incidence of genome-wide single nucleotide variants, though mutations found in early adapted populations were predominantly stochastic in nature. Prolonged adaptation under heterosubtypic immune selection resulted in the manifestation of highly virulent phenotypes that ablated vaccine mediated protection from mortality. High frequency mutations unique to escape phenotypes were identified within the polymerase encoding segments. These findings suggest that a suboptimial usage of population-wide universal influenza vaccine may drive formation of escape variants attributed to polygenic changes.

14.
Phys Imaging Radiat Oncol ; 25: 100407, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36655214

RESUMO

Background and purpose: Reduction of respiratory tumour motion is important in liver stereotactic body radiation therapy (SBRT) to reduce side effects and improve tumour control probability. We have assessed the distribution of use of voluntary exhale breath hold (EBH), abdominal compression (AC), free breathing gating (gating) and free breathing (FB), and the impact of these on treatment time. Materials and Methods: We assessed all patients treated in a single institution with liver SBRT between September 2017 and September 2021. Data from pre-simulation motion management assessment using fluoroscopic assessment of liver dome position in repeat breath holds, and motion with and without AC, was reviewed to determine liver dome position consistency in EBH and the impact of AC on motion. Treatment time was assessed for all fractions as time from first image acquisition to last treatment beam off. Results: Of 136 patients treated with 145 courses of liver SBRT, 68 % were treated in EBH, 20 % with AC, 7 % in gating and 5 % in FB. AC resulted in motion reduction < 1 mm in 9/26 patients assessed. Median treatment time was higher using EBH (39 min) or gating (42 min) compared with AC (30 min) or FB (24 min) treatments. Conclusions: Motion management in liver SBRT needs to be assessed per-patient to ensure appropriate techniques are applied. Motion management significantly impacts treatment time therefore patient comfort must also be taken into account when selecting the technique for each patient.

15.
Clin Colorectal Cancer ; 21(2): e102-e112, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34799240

RESUMO

BACKGROUND: To analyze the long-term outcomes and prognostic value of hematological parameters in anal cancer patients receiving intensity-modulated radiation therapy (IMRT). MATERIALS: Hospital records of consecutive patients with anal squamous cell carcinoma who received curative-intent IMRT according to a standardized contouring protocol between 2010 and 2020 were reviewed. Locoregional failure-free survival (LRFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) were estimated using the Kaplan-Meier method. Coverage of locoregional recurrences by the initial IMRT volumes were assessed. The prognostic value of pretreatment blood counts for PFS and OS were determined using Cox regression analysis. RESULTS: A total of 166 patients were analyzed with a median follow-up of 3.3 years. Forty-six percent and 54% of patients had Stage I-II and IIIA-B cancers, respectively. The 5-year LRFS, DMFS, PFS and OS were 81%, 89%, 65% and 76% respectively. Grade ≥ 3 toxicity occurred in 5% of patients. Of all patients who relapsed, 70% had only locoregional recurrence as first site of failure. Ninety percent of locoregional recurrences were in-field. Hemoglobin, neutrophil and platelet counts were associated with PFS on univariable analysis, but only cancer stage and p16 status remained prognostic on multivariable analysis. Patients with more advanced cancer stages also had higher baseline neutrophil counts. Performance status and neutrophil counts were prognostic for OS on multivariable analysis. CONCLUSION: This study affirms the long-term efficacy and safety of IMRT. Treatment resistance, rather than radiation geographic miss, is a major issue underpinning locoregional recurrences. Pretreatment blood counts were not validated to be independently prognostic for disease recurrence.


Assuntos
Neoplasias do Ânus , Radioterapia de Intensidade Modulada , Neoplasias do Ânus/radioterapia , Intervalo Livre de Doença , Humanos , Recidiva Local de Neoplasia , Prognóstico , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos
16.
Int J Radiat Oncol Biol Phys ; 114(5): 862-870, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35752407

RESUMO

PURPOSE: Medical operability is prognostic for survival after SABR in primary malignancies. This study investigated the prognostic significance of medical operability and total versus subtotal ablation of all oligometastatic disease sites. METHODS AND MATERIALS: Consecutive patients with 1 to 5 sites of active extracranial oligometastases had medical operability status and presence of subtotal versus total metastatic ablation recorded prospectively in an institutional database. We retrospectively compared overall survival (OS) and progression-free survival (PFS) for medically operable or inoperable patients and patients undergoing total or subtotal metastatic ablation. Secondary endpoints were patterns of failure, high-grade treatment toxic effects (Common Terminology Criteria for Adverse Events version 4.0), and freedom from systemic therapy. The threshold dose per fraction considered ablative was 8 Gy. RESULTS: A total of 401 patients with 530 treated oligometastases were included, with a median follow-up of 3 years. Three hundred and two and 99 patients had metachronous and synchronous presentations of oligometastatic disease, respectively. Common histologies included prostate (24%), lung (18%), gastrointestinal (19%), and breast (11%). More than 90% of doses delivered were Biologically Effective Dose [BED10]≥60 Gy. Cumulative incidence at 5 years of local-only failure was 6%, local and distant 2%, and distant-only 58%. The 3- and 5-year OS [95% confidence intervals {CIs}] were 68% [62-73] and 54% [47-61], and PFS was 20% [15-25] and 14% [10-20]. The 3- and 5-year freedom from systemic therapy [95% CIs] were 40% [34-46] and 31% [24-37], respectively. Seventy-six patients were inoperable and 325 were operable. Operability status was not prognostic for OS (adjusted hazard ratio [HR], 1.0; 95% CI, 0.6-1.7; P = .9) or for PFS (adjusted HR, 1.1; 95% CI, 0.8-1.6; P = .5). Total metastatic ablation was prognostic for OS (adjusted HR, 0.8; 95% CI, 0.4-0.9; P = .032) and for PFS (adjusted HR, 0.6; 95% CI, 0.4-0.8; P = .003). CONCLUSIONS: Medical operability was not prognostic in patients with oligometastatic disease treated with SABR. Total metastatic ablation was associated with superior OS and PFS compared with subtotal metastatic ablation. Our data support ablation of all sites of oligometastases wherever feasible.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Masculino , Humanos , Radiocirurgia/métodos , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Resultado do Tratamento , Prognóstico
17.
J Craniovertebr Junction Spine ; 13(3): 224-232, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36263337

RESUMO

Cat scratch disease (CSD), caused by Bartonella henselae, may atypically present with vertebral osteomyelitis. Antibiotic regimens are tailored to presentation, which is markedly variable and not well defined for any atypical disease. In cases of spinal instability, the use of antibiotics alone may not be sufficient. Atlantoaxial instability caused by osteomyelitis is a rare complication of CSD. In this report, we describe the rare case of vertebral osteomyelitis complicated by atlantoaxial instability, requiring both antibiotics and atlantoaxial fusion. We discuss our case, surgical technique, rationale, and outcome. In addition, we conducted a systematic review of the literature of vertebral osteomyelitis in pediatric secondary to B. henselae. A 2-year-old child presented with a 2-month history of irritability, fever, and rigid neck pain along with a recent history of feline exposure. Physical examination revealed cervical tenderness and decreased range of motion. Computed tomography (CT) showed osteolysis of the right C1 lateral mass and pars articularis; T1-weighted magnetic resonance imaging with contrast showed enhancement around the right C1 lateral mass. The titer for B. henselae was high. A diagnosis of cat scratch osteomyelitis with cervical instability was made, for which the patient underwent surgery with atlantoaxial fusion. Postoperative imaging demonstrated resolution of the contrast-enhanced lesion. At 6-year follow-up, the patient showed no signs of residual complications from surgical intervention with a solid fusion. Our review revealed 44 cases of pediatric CSD vertebral osteomyelitis. Conservative management with antibiotic employed in 86% while antibiotics with surgical intervention in 14% of the cases. Surgical intervention was most often in the form of incision for drainage and decompression without fusion. Average follow-up 10 months with 86% achieved complete resolution. Cervical instability caused by osteolysis is a rare complication of CSD. This can subsequently lead to vertebral instability, requiring definitive surgical intervention.

18.
J Acoust Soc Am ; 130(3): 1503-14, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21895090

RESUMO

Three experiments measured the perceived continuity of two pure tones "flankers" through a masker containing a silence. Experiment 1 used a 2I-2AFC procedure; one interval contained two noise bursts separated by a silent gap, and the other contained two noise bursts separated by a tone of the same duration as the silence. Discrimination between masker conditions was very accurate when the flankers were absent but was impaired substantially when the flankers were present. This was taken as evidence that illusory flanker continuity during the silent gap was heard as similar to the physical presence of a tone in the gap. In experiment 2, performance remained poor when the flankers were frequency glides aligned along a common trajectory. Performance improved significantly when the flankers were misaligned in trajectory. In experiment 3, listeners rated directly perceived flanker continuity. Strong continuity was reported in the silent gap conditions for which poor performance had been observed in experiments 1 and 2. These findings show that continuity may be heard through a masker that cannot mask a physically continuous tone but can mask the flankers' offset and onset. The results are explained in terms of the perceptual grouping of onsets and offsets of the flankers.


Assuntos
Ruído/efeitos adversos , Mascaramento Perceptivo , Percepção da Altura Sonora , Estimulação Acústica , Adulto , Análise de Variância , Audiometria de Tons Puros , Limiar Auditivo , Discriminação Psicológica , Humanos , Fatores de Tempo , Adulto Jovem
19.
Dermatol Online J ; 17(10): 1, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22031627

RESUMO

Plate-like osteoma cutis is a rare disorder that has been historically classified as a congenital syndrome. It has a possible relationship to a mutation in the gene (GNAS1) that encodes the α-subunit of the stimulatory G protein, which regulates adenyl cyclase activity. We report a case of extensive plaque-like masses on the scalp and face with no abnormalities in calcium or phosphate metabolism and no preceding inflammatory cutaneous conditions. With less than ten reported cases, to our knowledge, this is one the few cases of acquired plate-like osteoma cutis described in the literature.


Assuntos
Ossificação Heterotópica/patologia , Osteoma/patologia , Dermatopatias/patologia , Cálcio/metabolismo , Cromograninas , Dermatoses Faciais/diagnóstico , Dermatoses Faciais/patologia , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Humanos , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/diagnóstico , Ossificação Heterotópica/genética , Ossificação Heterotópica/terapia , Osteoma/genética , Osteoma/terapia , Fósforo/metabolismo , Dermatoses do Couro Cabeludo/diagnóstico , Dermatoses do Couro Cabeludo/patologia , Dermatopatias/diagnóstico , Dermatopatias/genética , Dermatopatias/terapia , Coxa da Perna , Tórax
20.
Dermatol Online J ; 17(10): 2, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22031628

RESUMO

Anetoderma is an uncommon dermatosis that manifests as discrete foci of well-circumscribed, atrophic skin. The condition can be idiopathic or can be secondary to a number of associated cutaneous diseases. Whereas the pathophysiologic mechanisms remain unknown, anetoderma results from diminished elastic fibers in the dermis. We present an unusual case of localized, lenticular anetoderma in a man with HIV, a history of syphilis, and lichen planus. Both of these infections have been associated with anetoderma. Although his lesions are vaguely reminiscent of a variant of syphilitic anetoderma described in the 1930s, they are confined to a smaller anatomic distribution, differ in size, and have a papular appearance. As anetoderma can develop in the context of infectious disease, a diagnosis of anetoderma should trigger a thorough examination and evaluation for treatable concomitant illnesses.


Assuntos
Anetodermia/etiologia , Infecções por HIV/complicações , Líquen Plano/complicações , Sífilis/complicações , Anetodermia/diagnóstico , Anetodermia/patologia , Hepatite C Crônica/complicações , Humanos , Masculino , Pessoa de Meia-Idade
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