Time filter

Source Type

South Brisbane, Australia

Bridge P.,Queensland University of Technology | Carmichael M.-A.,Queensland University of Technology | Brady C.,Radiation Oncology Materials Center | Dry A.,Cancer Care Services Royal Brisbane Womens Hospital Herston
Journal of Medical Radiation Sciences | Year: 2013

Introduction: Undergraduate students studying the Bachelor of Radiation Therapy at Queensland University of Technology (QUT) attend clinical placements in a number of department sites across Queensland. To ensure that the curriculum prepares students for the most common treatments and current techniques in use in these departments, a curriculum matching exercise was performed. Methods: A cross-sectional census was performed on a pre-determined "Snapshot" date in 2012. This was undertaken by the clinical education staff in each department who used a standardized proforma to count the number of patients as well as prescription, equipment, and technique data for a list of tumour site categories. This information was combined into aggregate anonymized data. Results: All 12 Queensland radiation therapy clinical sites participated in the Snapshot data collection exercise to produce a comprehensive overview of clinical practice on the chosen day. A total of 59 different tumour sites were treated on the chosen day and as expected the most common treatment sites were prostate and breast, comprising 46% of patients treated. Data analysis also indicated that intensity-modulated radiotherapy (IMRT) use is relatively high with 19.6% of patients receiving IMRT treatment on the chosen day. Both IMRT and image-guided radiotherapy (IGRT) indications matched recommendations from the evidence. Conclusion: The Snapshot method proved to be a feasible and efficient method of gathering useful data to inform curriculum matching. Frequency of IMRT use in Queensland matches or possibly exceeds that indicated in the literature. It is recommended that future repetition of the study be undertaken in order to monitor trends in referral patterns and new technology implementation. © 2013 The Authors. Journal of Medical Radiation Sciences published by Wiley Publishing Asia Pty Ltd on behalf of Australian Institute of Radiography and New Zealand Institute of Medical Radiation Technology.

Lin C.,Cancer Care Services | Lin C.,University of Queensland | Tripcony L.,Cancer Care Services | Keller J.,Cancer Care Services | And 4 more authors.
Clinical Oncology | Year: 2013

Aims: To review the outcome of patients with non-melanomatous carcinoma of the skin of the head and neck with perineural infiltration (PNI) with clinical features treated with radiotherapy. Materials and methods: Between 1991 and 2004, 56 patients with non-melanomatous skin carcinoma with PNI with clinical features were identified from the institution's oncology database. All patients had radiotherapy as either definitive or adjuvant treatment. The factors that affected outcome were analysed. The primary end point was the 5 year relapse-free survival (RFS) from the time of diagnosis of PNI. Results: The overall 5 year RFS for the whole group was 48%. Squamous histology had a more unfavourable outcome than basal cell histology (5 year RFS: 39% versus 80%; P = 0.07). Tumours located in the distribution of the cranial nerves V1 and V2 had a worse outcome than tumours at other sites (5 year RFS: 33% versus 72%, P = 0.056). Those with multiple cranial nerve involvement did worse than those with single nerve involvement (27% versus 62%, P = 0.1). The pattern of relapse was predominantly local (87%), with a low rate (15%) of successful salvage. Conclusion: Radiotherapy with or without surgery is curative in about half head and neck cutaneous non-melanomatous carcinomas with clinical PNI. The frequent local failure suggests that improvements in local treatment are required. © 2013 The Royal College of Radiologists.

Hutchinson A.,Radiation Oncology Materials Center | Bridge P.,Queensland University of Technology
Journal of Radiotherapy in Practice | Year: 2014

Purpose To establish whether the use of a passive or active technique of planning target volume (PTV) definition and treatment methods for non-small cell lung cancer (NSCLC) deliver the most effective results. This literature review assesses the advantages and disadvantages in recent studies of each, while assessing the validity of the two approaches for planning and treatment. Methods A systematic review of literature focusing on the planning and treatment of radiation therapy to NSCLC tumours. Different approaches which have been published in recent articles are subjected to critical appraisal in order to determine their relative efficacy. Results Free-breathing (FB) is the optimal method to perform planning scans for patients and departments, as it involves no significant increase in cost, workload or education. Maximum intensity projection (MIP) is the fastest form of delineation, however it is noted to be less accurate than the ten-phase overlap approach for computed tomography (CT). Although gating has proven to reduce margins and facilitate sparing of organs at risk, treatment times can be longer and planning time can be as much as 15 times higher for intensity modulated radiation therapy (IMRT). This raises issues with patient comfort and stabilisation, impacting on the chance of geometric miss. Stereotactic treatments can take up to 3 hours to treat, along with increases in planning and treatment, as well as the additional hardware, software and training required. Conclusion Four-dimensional computed tomography (4DCT) is superior to 3DCT, with the passive FB approach for PTV delineation and treatment optimal. Departments should use a combination of MIP with visual confirmation ensuring coverage for stage 1 disease. Stages 2-3 should be delineated using ten-phases overlaid. Stereotactic and gated treatments for early stage disease should be used accordingly; FB-IMRT is optimal for latter stage disease. © 2014 Cambridge University Press.

Owen R.,Radiation Oncology Materials Center | Owen R.,Peter MacCallum Cancer Center | Owen R.,University of Sydney | Kron T.,Peter MacCallum Cancer Center | And 4 more authors.
Medical Dosimetry | Year: 2011

Fiducial markers (FMs) are commonly used as a correction technique for interfraction translations of the prostate. The aim of this investigation was to determine the magnitude of prostate rotations using 2 methods: FM coordinates and the anatomical border of the prostate and rectum. Daily computed tomography (CT) scans (n = 346) of 10 prostate cancer patients with 3 implanted FMs were acquired using the CT on rails. FM coordinates were used to determine rotation in the sagittal, transverse, and coronal planes, and CT contours of the prostate and rectum were used to determine rotation along the sagittal plane. An adaptive technique based on a subset of images (n = 6; planning and first 5 treatment CTs) to reduce systematic rotation errors in the sagittal plane was tested. The standard deviation (SD) of systematic rotation from FM coordinates was 7.6°, 7.7°, and 5.0° in the sagittal, transverse and coronal planes. The corresponding SD of random error was 10.2°, 15.8°, and 6.5°. Errors in the sagittal plane, determined from prostate and rectal contours, were 10.1° (systematic) and 7.7° (random). These results did not correlate with rotation computed from FM coordinates (r = -0.017; p = 0.753, n = 337). The systematic error could be reduced by 43% to 5.6° when the mean prostate position was estimated from 6 CT scans. Prostate rotation is a significant source of error that appears to be more accurately determined using the anatomical border of the prostate and rectum rather than FMs, thus highlighting the utility of CT image guidance. © 2011.

Jones S.,Radiation Oncology Materials Center | Fitzgerald R.,Princess Alexandra Hospital | Owen R.,Radiation Oncology Materials Center | Ramsay J.,Radiation Oncology Materials Center
Journal of Medical Radiation Sciences | Year: 2015

Introduction: The magnitude of intra- and inter-fractional variation in the set up of breast cancer patients treated with tangential megavoltage photon beams was investigated using an electronic portal imaging device (EPID). Methods: Daily cine-EPID images were captured during delivery of the tangential fields for ten breast cancer patients treated in the supine position. Measurements collected from each image included the central lung distance (CLD), central flash distance (CFD), superior axial measurement (SAM) and the inferior axial measurement (IAM). The variation of motion within a fraction (intra-fraction) and the variation between fractions (inter-fraction) was analysed to quantify set up variation and motion due to respiration. Results: Altogether 3775 EPID images were collected from 10 patients. The effect of respiratory motion during treatment was <0.1 cm standard deviation (SD) in the anterior-posterior (AP) direction. The inter-fraction movement caused by variations in daily set up was larger at 0.28 cm SD in the AP direction. Superior-inferior (SI) variation was more difficult to summarise and proved unreliable as the measurements were taken to an ambiguous point on the images. It was difficult to discern true SI movement from that implicated by AP movement. Conclusion: There is minimal intra-fractional chest wall motion due to respiration during treatment. Inter-fractional variation was larger, however, on average it remained within departmental tolerance (0.5 cm) for set up variations. This review of our current breast technique provides confidence in the feasibility of utilising advanced treatment techniques (field-in-field, intensity modulated radiotherapy or volumetric modulated arc therapy) following a review of the current imaging protocol. © 2014 The Authors.

Discover hidden collaborations