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1.
J Cancer Educ ; 36(3): 646-651, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-31873855

RESUMO

The purpose of this study is to evaluate radiation oncology (RO)-specific education, confidence and knowledge of junior doctors in Australian teaching hospitals. A 38-item web-based survey was emailed to prevocational junior doctors working in Australian hospitals in New South Wales (NSW), Australian Capital Territory (ACT) and Queensland (QLD) between November 2017 and January 2018. The survey evaluated RO educational and clinical exposure of participants during medical school, and prevocational training and their confidence and knowledge of the specialty. A total of 183 respondents across 17 Australian hospital networks completed the survey. During medical school, 53.4% had RO incorporated into their formal curriculum, 19.5% had no formal lectures and 51.7% had never visited a RO department. As a junior doctor, 73.8% of respondents did not receive any formal RO education. When compared with other oncology specialties, fewer junior doctors were confident in consulting the RO team (21.0%) compared with medical oncology (42.0%), palliative care (75.2%) and haematology (40.1%). Majority of respondents (61.6%) showed limited understanding of radiation safety. On multivariate sub-group analysis, both confidence and knowledge in RO improved when RO was incorporated into the formal medical school curriculum. This survey highlights the current low confidence and poor knowledge standard amongst Australian junior doctors on RO due to inadequate teaching during medical school and prevocational training and suggests improvement through standardisation of formal RO curriculum teaching within medical school and prevocational training.


Assuntos
Radioterapia (Especialidade) , Faculdades de Medicina , Austrália , Currículo , Humanos , Corpo Clínico Hospitalar , Radioterapia (Especialidade)/educação , Inquéritos e Questionários
2.
J Cancer Educ ; 35(6): 1227-1236, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31332623

RESUMO

This study aimed to determine final year students' core oncology and radiation oncology knowledge and attitudes about the quality of teaching in medical programmes delivered in Australia and New Zealand. Does the modern medical programme provide core oncology skills in this leading global cause of mortality and morbidity? An online survey was distributed between April and June 2018 and completed by 316 final year students across all 21 medical schools with final year cohorts in Australia and New Zealand. The survey examined teaching and clinical exposure, attitudes and core knowledge for oncology and radiation oncology. Several questions from a survey done of graduates in 2001 were repeated for comparison. We found that clinical exposure to oncology and its disciplines is low. Students rated oncology and haematology the worst taught medical specialties at medical school. Students reported the most confidence identifying when surgical management of cancer may be indicated and much lower levels of confidence identifying when systemic therapy and radiation therapy may be helpful. The majority of students had no formal course content on radiation therapy and more than one third of final year students erroneously believed that external beam radiation therapy turned patients radioactive. Exposure to oncology practice and the teaching of core oncology knowledge remains low for medical students in Australia and New Zealand. Many areas of oncology teaching and knowledge have worsened for medical students in Australia and New Zealand over the past 20 years. Well-established gaps in the core oncology knowledge of medical graduates must be urgently addressed given the increasing incidence of cancer and ongoing underutilisation of radiation therapy in particular.


Assuntos
Currículo/normas , Educação de Graduação em Medicina/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Oncologia/educação , Neoplasias/terapia , Radioterapia (Especialidade)/educação , Estudantes de Medicina/psicologia , Austrália , Educação de Graduação em Medicina/métodos , Educação de Graduação em Medicina/tendências , Feminino , Humanos , Masculino , Nova Zelândia , Inquéritos e Questionários
3.
Artigo em Inglês | MEDLINE | ID: mdl-38499253

RESUMO

PURPOSE: Dose-escalated radiation therapy is associated with better biochemical control at the expense of toxicity. Stereotactic body radiation therapy (SBRT) with dose escalation to the dominant intraprostatic lesion (DIL) provides a logical approach to improve outcomes in high-risk disease while limiting toxicity. This study evaluated the toxicity and quality of life (QoL) with CyberKnife-based SBRT and simultaneous integrated boost in localized prostate cancer. METHODS AND MATERIALS: Eligible participants included newly diagnosed, biopsy-proven unfavorable intermediate- to high-risk localized prostate cancer (at least 1 of the following: Gleason ≥4+3, magnetic resonance imaging(MRI)-defined T3a N0, prostate-specific antigen ≥20) with up to 2 MRI-identified DILs. Participants received 36.25 Gy in 5 fractions on alternative days with a simultaneous boost to DIL up to 47.5 Gy as allowed by organ-at-risk constraints delivered by CyberKnife. All participants received androgen deprivation therapy. The primary outcome measure was acute grade 2+ genitourinary toxicity. Acute and late genitourinary and gastrointestinal toxicity using Radiation Therapy Oncology Group scoring, biochemical parameters, International Prostate Symptom Score, International Index of Erectile Function 5, and EQ-5D QoL outcomes were assessed. RESULTS: Between 2013 and 2023, 20 participants were enrolled with a median follow-up of 30 months. The median D95 dose to DIL was 47.43 Gy. Cumulative acute grade 2+ genitourinary and gastrointestinal toxicity were 25% and 30%, respectively. One patient developed acute grade 3 genitourinary toxicity (5%). There is no late grade 3 genitourinary or gastrointestinal toxicity to date. International Prostate Symptom Score and urinary QoL scores recovered to baseline by 6 months. Patient-reported outcomes showed no significant change in EQ-5D QoL scores at 12 weeks and 1 year. There are no cases of biochemical relapse reported to date. CONCLUSIONS: CyberKnife SBRT-delivered dose of 36.25 Gy to the prostate with a simultaneous integrated boost up to 47.5 Gy is well tolerated. Acute and late genitourinary and gastrointestinal toxicity rates are comparable to other contemporary SBRT trials and series with focal boost.

4.
Adv Mater ; 35(34): e2107023, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35025119

RESUMO

Ultrashort optical pulses are integral to probing various physical, chemical, and biological phenomena and feature in a whole host of applications, not least in data communications. Super- and subluminal pulse propagation and dispersion management (DM) are two of the greatest challenges in producing or counteracting modifications of ultrashort optical pulses when precise control over pulse characteristics is required. Progress in modern photonics toward integrated solutions and applications has intensified this need for greater control of ultrafast pulses in nanoscale dimensions. Metamaterials, with their unique ability to provide designed optical properties, offer a new avenue for temporal pulse engineering. Here an epsilon-near-zero metamaterial is employed, exhibiting strong nonlocal (spatial dispersion) effects, to temporally shape optical pulses. The authors experimentally demonstrate, over a wide bandwidth of tens of THz, the ability to switch from sub to superluminal and further to "backward" pulse propagation (±c/20) in the same metamaterial device by simply controlling the angle of illumination. Both the amplitude and phase of a 10 ps pulse can be controlled through DM in this subwavelength device. Shaping ultrashort optical pulses with metamaterials promises to be advantageous in laser physics, optical communications, imaging, and spectroscopy applications using both integrated and free-standing devices.

5.
Radiother Oncol ; 180: 109461, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36634852

RESUMO

BACKGROUND AND PURPOSE: The use of SBRT for the treatment of oligometastatic prostate cancer is increasing rapidly. While consensus guidelines are available for non-spinal bone metastases practice continues to vary widely. The aim of this study is to look at inter-observer variability in the contouring of prostate cancer non-spinal bone metastases with different imaging modalities. MATERIALS AND METHODS: 15 metastases from 13 patients treated at our centre were selected. 4 observers independently contoured clinical target volumes (CTV) on planning CT alone, planning CT with MRI fusion, planning CT with PET-CT fusion and planning CT with both MRI and PET-CT fusion combined. The mean inter-observer agreement on each modality was compared by measuring the delineated volume, generalized conformity index (CIgen), and the distance of the centre of mass (dCOM), calculated per metastasis and imaging modality. RESULTS: Mean CTV volume delineated on planning CT with MRI and PET-CT fusion combined was significantly larger compared to other imaging modalities (p = 0.0001). CIgen showed marked variation between modalities with the highest agreement between planning CT + PET-CT (mean CIgen 0.55, range 0.32-0.73) and planning CT + MRI + PET-CT (mean CIgen 0.59, range 0.34-0.73). dCOM showed small variations between imaging modalities but a significantly shorter distance found on planning CT + PET-CT when compared with planning CT + PET-CT + MRI combined (p = 0.03). CONCLUSIONS: Highest consistency in CTV delineation between observers was seen with planning CT + PET-CT and planning CT + PET-CT + MRI combined.


Assuntos
Neoplasias Ósseas , Neoplasias da Próstata , Radiocirurgia , Planejamento da Radioterapia Assistida por Computador , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/radioterapia , Imageamento por Ressonância Magnética , Metástase Neoplásica/diagnóstico por imagem , Metástase Neoplásica/radioterapia , Variações Dependentes do Observador , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Tomografia Computadorizada por Raios X , Humanos , Masculino
6.
Clin Transl Radiat Oncol ; 25: 88-93, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33145444

RESUMO

INTRODUCTION: Dose escalation to dominant intraprostatic lesions (DILs) is a novel method to increase the therapeutic ratio in localised prostate cancer. The Stereotactic Prostate Augmented Radiotherapy with Cyberknife (SPARC) trial was designed to determine the feasibility of a focal boost defined with multiparametric magnetic resonance imaging (mpMRI) using stereotactic ablative body radiotherapy (SABR). MATERIALS AND METHODS: Patients were included with newly diagnosed intermediate to high risk prostate cancer with at least one of: Gleason score 4 + 3, stage T3a, or PSA > 20 ng/ml. Visible disease on mpMRI was mandatory and up to 2 separate nodules were allowed. All patients received androgen deprivation. Patients received 36.25 Gy in 5 fractions using CyberKnife® and the DIL received a simultaneous boost to a maximum of 47.5 Gy, as allowed by OAR constraints. Genitourinary (GU) and gastrointestinal (GI) toxicity was reported using the RTOG scoring criteria. International Index of Erectile Function (IIEF) and EQ-5D global health scores were regularly captured. RESULTS: An interim safety analysis was performed on the first 8 patients, recruited between July 2013 and December 2015. Median follow up was 56 months (range 50-74). Median D95 values for the prostate PTV and boost volume were 36.55 Gy (range 35.87-36.99) and 46.62 Gy (range 44.85-48.25) respectively. Of the dose constraints, 10/80 were not achieved but all were minor dose variations. Grade 2+ acute GU and GI toxicities were 37.5% respectively while grade 2+ late GU and GI toxicities were 12.5% and 0% respectively. IIEF and quality of life scores recovered over time and all patients remain in biochemical remission. CONCLUSION: The first patients have been successfully treated with prostate SABR and focal boost on the SPARC trial, with excellent adherence to the planning protocol. Toxicity and efficacy results are promising and further recruitment is underway.

7.
Nat Commun ; 10(1): 2967, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273210

RESUMO

While free electrons in metals respond to ultrafast excitation with refractive index changes on femtosecond time scales, typical relaxation mechanisms occur over several picoseconds, governed by electron-phonon energy exchange rates. Here, we propose tailoring these intrinsic rates by engineering a non-uniform electron temperature distribution through nanostructuring, thus, introducing an additional electron temperature relaxation channel. We experimentally demonstrate a sub-300 fs switching time due to the wavelength dependence of the induced hot electron distribution in the nanostructure. The speed of switching is determined by the rate of redistribution of the inhomogeneous electron temperature and not just the rate of heat exchange between electrons and phonons. This effect depends on both the spatial overlap between control and signal fields in the metamaterial and hot-electron diffusion effects. Thus, switching rates can be controlled in nanostructured systems by designing geometrical parameters and selecting wavelengths, which determine the control and signal mode distributions.

8.
J Med Imaging Radiat Oncol ; 62(6): 828-834, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30074292

RESUMO

INTRODUCTION: Radiation therapy is a core component of curative and palliative cancer treatment; however, its indications and benefits remain poorly understood across the medical profession. METHODS: An electronic survey focussing on curriculum content, teaching and assessment in radiation oncology and plans for curriculum change was developed. The Faculty of Radiation Oncology, Royal Australian and New Zealand College of Radiology (RANZCR) distributed the survey to all 24 Australian and New Zealand medical schools. The survey was conducted from November 2017 to January 2018 following ethics approval. RESULTS: Sixteen of the 24 (67%) medical Faculties in Australia and New Zealand responded. Ninety-four percent of Faculties had no formal radiation oncology curriculum. Most Faculties (87%) dedicated <15% of the total medical course to oncology, of which the majority (63%) dedicated <10% to radiation oncology. At least 50% of Faculties did not offer formal radiation oncology teaching to all students. When offered, students' exposure to radiation oncology was often <5 days over the entire course (44%). The majority of medical schools (73%) are planning curriculum changes in the next 5 years; however, most have no intention of changing radiation oncology teaching. CONCLUSION: Radiation oncology continues to be underrepresented in medical curricula throughout Australia and New Zealand with no plans for improvement by Faculties. This study supports the need for formal advocacy for improving radiation oncology education in medical schools and will form the basis of new national recommendations for radiation oncology curriculum development.


Assuntos
Currículo , Radioterapia (Especialidade)/educação , Faculdades de Medicina , Austrália , Educação de Graduação em Medicina , Humanos , Nova Zelândia , Inquéritos e Questionários
9.
J Med Radiat Sci ; 64(4): 259-265, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28805047

RESUMO

INTRODUCTION: To investigate the efficacy and toxicity of radiation therapy (RT) after radical prostatectomy (RP) for prostate cancer at Radiation Oncology Centres, Toowoomba. METHODS: The electronic medical records of 130 consecutive patients with histologically proven prostate adenocarcinoma who underwent post-prostatectomy RT between January 2008 and December 2014 were analysed. Primary endpoint was Biochemical Recurrence (BCR) after RT. BCR was defined by PSA > 0.2 ng/mL and BCR endpoints were analysed using Kaplan-Meier methods. The impact of RT technique and the rates of acute and late toxicities are also reported. Toxicities were graded according to Radiation Therapy Oncology Group (RTOG) criteria. RESULTS: Median follow-up time after RT (regardless of technique) was 28 months. BCR occurred in 32 of the 126 patients (25%) whose prostate specific antigen (PSA) levels have been monitored post-RT. At 24 and 36 months, 85% and 75% of patients were BCR-free, respectively. Patients with a pre-RT PSA above 0.2 ng/mL had a higher probability of recurrence than patients with values below 0.2 ng/mL (P = 0.03). RT technique, pelvic nodal irradiation, androgen deprivation therapy, T staging or surgical margin did not significantly impact BCR results. No patient experienced acute toxicities greater than grade 2. Grade 1 or 2 late gastrointestinal (GI) toxicity occurred in 11% and 1 patient experienced a grade 3 event. 12% of patients developed grade 1 or 2 late genitourinary (GU) toxicity, with evidence of grade 3 severity in only 1 patient. Evidence of a trend in reduction in late GI toxicity with the use of intensity modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT) was apparent but not with late GU toxicity. CONCLUSION: At our regional centre, early RT (PSA < 0.2 ng/mL) was associated with significant improvement in BCR-free survival. Rates of toxicity mirror those of landmark trials which suggest no detriment for our regional prostate cancer patients. The use of IMRT/VMAT techniques was associated with a trend towards reduced rates of GI toxicity.


Assuntos
Adenocarcinoma/radioterapia , Neoplasias da Próstata/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Serviços de Saúde Rural/estatística & dados numéricos , Adenocarcinoma/epidemiologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Austrália , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prostatectomia , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/cirurgia
10.
Asia Pac J Clin Oncol ; 12(4): 415-420, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27453519

RESUMO

AIM: To compare patient demographics, prophylactic cranial irradiation (PCI) utilization and overall survival (OS) of patients with small cell lung cancer (SCLC) referred to a large tertiary center with those reported in large clinical trials. PATIENTS AND METHODS: A retrospective review was conducted of consecutive patients with limited stage (LS) and extensive stage (ES) SCLC diagnosed at the Princess Alexandra Hospital between January 2008 and December 2013. RESULTS: Two hundred and three patients with a mean age of 65.4 (±10.7) years were followed for a median duration of 7.6 months (range 0.5-76.5). At diagnosis, 129 (64%) patients had ES-SCLC, including 39 (19.2%) with cerebral metastases. Median OS in LS-SCLC patients receiving PCI was 18.8 months (0.9-69.4), compared with 8.2 months (0.1-34.4) in patients who did not receive PCI (P < 0.001). Median OS in the ES-SCLC cohort receiving PCI was 13.6 months (5.2-37.5) compared to 5.6 months (0.1-73.6) in patients who did not receive the therapy (P < 0.001). There was a significant improvement in intracranial disease-free survival of 7.1 months in patients with ES-SCLC who received PCI. Forty-two LS-SCLC patients (57%) did not receive PCI due to patient suitability. CONCLUSIONS: In our SCLC cohort, median OS following PCI in LS-SCLC and ES-SCLC is comparable to published data. PCI use at our institution was lower than utilization rates in large meta-analyses, predominately due to poor chemotherapy tolerance and patient suitability. This may be more representative of patients treated in clinical practice rather than those recruited into large phase III trials.


Assuntos
Neoplasias Encefálicas/prevenção & controle , Irradiação Craniana , Neoplasias Pulmonares/patologia , Carcinoma de Pequenas Células do Pulmão/prevenção & controle , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carcinoma de Pequenas Células do Pulmão/mortalidade , Carcinoma de Pequenas Células do Pulmão/secundário , Taxa de Sobrevida
11.
J Med Radiat Sci ; 63(3): 155-60, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27648279

RESUMO

INTRODUCTION: The aim of this study was to assess variation in prostate contouring 12 months following a structured interactive educational intervention (EI) and to test the hypothesis that EIs positively impact on prostate contouring accuracy and consistency long term. METHODS: A common set of computed tomography (CT) and magnetic resonance imaging (MRI) data sets were used to assess prostate contouring consistency before, immediately after and 12 months following an EI. No further EIs were provided after the initial EI. Contour variation was assessed using the volume ratio (VR), defined as the ratio of the encompassing volume to common volume. RESULTS: Of the original five radiation oncologists (ROs) at baseline, four completed all assessments, and one was unavailable at 12 months follow-up. At 12 months, mean VR deteriorated by 3.2% on CT and 1.9% on MRI compared to immediately post EI. Overall, compared to the pre-EI baseline VR, an improvement of 11.4% and 10.8% was demonstrated on CT and MRI, respectively. CONCLUSION: Good retention of applied knowledge 12 months following an EI on prostate contouring was demonstrated. This study advocates for EIs to be included as part of continuing medical education to reduce contour variation among ROs and improve knowledge retention long term.


Assuntos
Educação Médica Continuada , Interpretação de Imagem Assistida por Computador/normas , Imageamento por Ressonância Magnética/normas , Neoplasias da Próstata/diagnóstico por imagem , Radioterapia (Especialidade)/educação , Tomografia Computadorizada por Raios X/normas , Humanos , Masculino , Variações Dependentes do Observador
12.
Case Rep Oncol ; 8(2): 332-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26351442

RESUMO

INTRODUCTION: Osteoradionecrosis (ORN) of the chest wall is a rare complication after whole-breast radiotherapy (RT). Herein, we report a case of ORN involving the underlying ribs following adjuvant whole-breast RT using standard fractionation and conduct a review of the literature. CASE REPORT: A previously well 43-year-old female with right-sided, early-stage, node-negative breast cancer was treated with breast-conserving surgery. She subsequently underwent adjuvant whole-breast RT receiving 50 Gy in 25 fractions over 5 weeks using standard tangential photon fields with 6 MV photons followed by an electron boost of 10 Gy in 5 fractions according to International Commission on Radiation Units (ICRU) requirements. Eleven months after RT, the patient developed right lateral chest wall pain, with magnetic resonance imaging (MRI) demonstrating two fractures involving the underlying right fifth and sixth ribs associated with fatty marrow changes in the second to sixth ribs, thus raising the possibility of ORN. Treatments including hyperbaric oxygen, pentoxifylline and vitamin E were used with symptomatic improvements. There was demonstrable resolution on follow-up MRI at 2.5 years. CONCLUSION: The incidence of ORN utilising modern RT techniques and standard fractionation is rare. Numerous treatments are available, with variable response rates. Emerging evidence of predictive gene profiling to estimate the risk of radiation sensitivity may assist in individualising preventative strategies to mitigate the risk of ORN.

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