A comparison between radiation therapists and medical specialists in the use of kilovoltage cone-beam computed tomography scans for potential lung cancer radiotherapy target verification and adaptation
Watt S.C.,Liverpool and Macarthur Cancer Therapy CentresNSW |
Watt S.C.,University of Sydney |
Watt S.C.,Ingham Institute for Applied Medical Research |
Vinod S.K.,Liverpool and Macarthur Cancer Therapy CentresNSW |
And 14 more authors.
Medical Dosimetry | Year: 2016
Target volume matching using cone-beam computed tomography (CBCT) is the preferred treatment verification method for lung cancer in many centers. However, radiation therapists (RTs) are trained in bony matching and not soft tissue matching. The purpose of this study was to determine whether RTs were equivalent to radiation oncologists (ROs) and radiologists (RDs) in alignment of the treatment CBCT with the gross tumor volume (GTV) defined at planning and in delineating the GTV on the treatment CBCT, as may be necessary for adaptive radiotherapy. In this study, 10 RTs, 1 RO, and 1 RD performed a manual tumor alignment and correction of the planning GTV to a treatment CBCT to generate an isocenter correction distance for 15 patient data sets. Participants also contoured the GTV on the same data sets. The isocenter correction distance and the contoured GTVs from the RTs were compared with the RD and RO. The mean difference in isocenter correction distances was 0.40 cm between the RO and RD, 0.51 cm between the RTs, and RO and 0.42 cm between the RTs and RD. The 95% CIs were smaller than the equivalence limit of 0.5 cm, indicating that the RTs were equivalent to the RO and RD. For GTV delineation comparisons, the RTs were not found to be equivalent to the RD or RO. The alignment of the planning defined GTV and treatment CBCT using soft tissue matching by the RTs has been shown to be equivalent to those by the RO and RD. However, tumor delineation by the RTs on the treatment CBCT was not equivalent to that of the RO and RD. Thus, it may be appropriate for RTs to undertake soft tissue alignment based on CBCT; however, further investigation may be necessary before RTs undertake delineation for adaptive radiotherapy purposes. © 2016 American Association of Medical Dosimetrists.
Thom S.R.,University of Maryland Baltimore County |
Bennett M.,Prince of Wales HospitalNSW |
Banham N.D.,Fiona Stanley Hospital |
Chin W.,University of California at Los Angeles |
And 19 more authors.
Journal of Applied Physiology | Year: 2015
Decompression sickness (DCS) is a systemic disorder, assumed due to gas bubbles, but additional factors are likely to play a role. Circulating microparticles (MPs)-vesicular structures with diameters of 0.1-1.0 =m-have been implicated, but data in human divers have been lacking. We hypothesized that the number of blood-borne, Annexin V-positive MPs and neutrophil activation, assessed as surface MPO staining, would differ between self-contained underwater breathing-apparatus divers suffering from DCS vs. asymptomatic divers. Blood was analyzed from 280 divers who had been exposed to maximum depths from 7 to 105 meters; 185 were control/asymptomatic divers, and 90 were diagnosed with DCS. Elevations of MPs and neutrophil activation occurred in all divers but normalized within 24 h in those who were asymptomatic. MPs, bearing the following proteins: CD66b, CD41, CD31, CD142, CD235, and von Willebrand factor, were between 2.4- and 11.7-fold higher in blood from divers with DCS vs. asymptomatic divers, matched for time of sample acquisition, maximum diving depth, and breathing gas. Multiple logistic regression analysis documented significant associations (P = 0.001) between DCS and MPs and for neutrophil MPO staining. Effect estimates were not altered by gender, body mass index, use of nonsteroidal antiinflammatory agents, or emergency oxygen treatment and were modestly influenced by divers' age, choice of breathing gas during diving, maximum diving depth, and whether repetitive diving had been performed. There were no significant associations between DCS and number of MPs without surface proteins listed above. We conclude that MP production and neutrophil activation exhibit strong associations with DCS. © 2015 the American Physiological Society.
Kang Y.-J.,Prince of Wales Clinical School |
Kang Y.-J.,Cancer Research Division |
Kang Y.-J.,University of Sydney |
O'Connell D.L.,Cancer Research Division |
And 15 more authors.
Cancer Epidemiology | Year: 2015
Prior work estimating optimal treatment utilisation rates for cervical cancer has focused on radiotherapy or chemotherapy, using proportions of patients with clinical indications for specific treatment strategies which were obtained from the published literature. Objectives: To estimate optimal uptake rates for surgery, radiotherapy, chemotherapy and chemo-radiotherapy for cervical cancer treatment in Australia and Canada, and to quantify the differences in the optimal and the observed treatment utilisation rates in a large cancer facility from each country. Methods: A decision tree was constructed to reflect treatments according to guidelines and current practice (in 1999-2008) in each setting. Detailed patterns of care data from a large cancer facility in each country were obtained, and the observed stage distribution and proportions of patients with each clinical indication were used as inputs. Results: The estimated overall optimal treatment rates for cervical cancer in Australia and Canada differed, largely due to the difference in the stage distribution at diagnosis in the two settings; 72% vs 54% with FIGO IA-IIA disease, respectively. The estimated optimal rates for surgery, radiotherapy, chemotherapy and chemo-radiotherapy in Australia were 63% (95% credible interval: 61-64%), 52% (53-56%), 36% (35-38%) and 36% (35-38%), respectively. The corresponding rates in Canada were 38% (36-39%), 68% (68-71%), 51% (49-52%) and 50% (49-51%), respectively. The absolute differences between the optimal and the observed rates were similar between the two settings; the absolute differences for chemotherapy and chemo-radiotherapy uptake were more pronounced (9-15% less than optimal) than those for surgery and radiotherapy uptake (within 5% of optimal). Conclusions: This is the first study to use detailed patterns of care data in multiple settings to compare optimal and observed rates for all cervical cancer treatment modalities. We found optimal treatment rates were largely dependent on the overall stage distribution. In Australia and Canada, observed surgery rates, as measured in the two large cancer facilities, were similar to the estimated optimal rates, whereas radiotherapy, chemotherapy and chemo-radiotherapy appeared to be under-utilised. © 2015 Elsevier Ltd.
Buckley C.,Queensland Childrens Medical Research Institute |
Buckley C.,University of Queensland |
Trembizki E.,Queensland Childrens Medical Research Institute |
Trembizki E.,University of Queensland |
And 16 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2016
Objectives: The objective of this study was to develop a real-time PCR method for specific detection of the gonococcal GyrA amino acid 91 locus directly in clinical samples so as to predict Neisseria gonorrhoeae ciprofloxacin susceptibility. Methods: The real-time PCR assay, GyrA91-PCR, was designed using two probes, one for detection of the WT S91 sequence and the other for detection of the S91F alteration. The performance of the assay was initially assessed using characterized N. gonorrhoeae isolates (n = 70), a panel of commensal Neisseria and Moraxella species (n = 55 isolates) and clinical samples providing negative results by a commercial N. gonorrhoeae nucleic acid amplification test (NAAT) method (n = 171). The GyrA91-PCR was then applied directly to N. gonorrhoeae NAAT-positive clinical samples (n = 210) from the year 2014 for which corresponding N. gonorrhoeae isolates with susceptibility results were also available. Results: The GyrA91-PCR accurately characterized the GyrA 91 locus of all 70 N. gonorrhoeae isolates (sensitivity = 100%, 95% CI = 94.9%-100%), whereas all non-gonococcal isolates and N. gonorrhoeae NAAT-negative clinical samples gave negative results by the GyrA91-PCR (specificity = 100%, 95% CI = 98.4%-100%). When applied to the 210 N. gonorrhoeae NAAT-positive clinical samples, the GyrA91-PCR successfully characterized 195 samples (92.9%, 95% CI = 88.5%-95.9%). When compared with the corresponding bacterial culture results, positivity by the GyrA91-PCR WT probe correctly predicted N. gonorrhoeae susceptibility to ciprofloxacin in 161 of 162 (99.4%, 95% CI = 96.6%-99.9%) samples. Conclusions: The use of a PCR assay for detection of mutation in gyrA applied directly to clinical samples can predict ciprofloxacin susceptibility in N. gonorrhoeae. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.
Padmanabhan S.,Prince of Wales HospitalNSW |
Wagstaff A.,Prince of Wales HospitalNSW |
Tung V.,Prince of Wales HospitalNSW |
Tung V.,University of New South Wales |
And 4 more authors.
Diabetes Research and Clinical Practice | Year: 2014
We recorded gestational weight gain (GWG) and change in body mass index (BMI) at 28 weeks gestation in 343 vs. 339 women with and without gestational diabetes (GDM). GDM was associated with a greater increment in BMI, but not with increased GWG in kilograms. © 2014.