Clinical and Translational Radiation Oncology, 2017
Background: This prospective study aims to determine the impact of PET/CT on radiotherapy plannin... more Background: This prospective study aims to determine the impact of PET/CT on radiotherapy planning and outcomes in patients with oesophageal cancer. Methods: All patients underwent PET/CT scanning in the radiotherapy treatment position, and received treatment planned using the PET/CT dataset. GTV was defined separately on PET/CT (GTV-PET) and CT (GTV-CT) datasets. A corresponding PTV was generated for each patient. Volumetric and spatial analysis quantified the proportion of FDG-avid disease not included in CT-based volumes. Clinical data was collected to determine locoregional control and overall survival rates. Results: 13 (24.1%) of 57 accrued patients had metastatic disease detected on PET. Median follow up was 4 years. FDG-avid disease would have been excluded from GTV-CT in 29 of 38 patients (76%). In 5 patients, FDG-avid disease would have been completely excluded from the PTV-CT. GTV-CT underestimated the cranial and caudal extent of FDG-avid tumour in 14 (36%) and 10 (26%) patients. 4-Year overall survival and locoregional failure free survival were 37% and 65%. Conclusions: PET/CT altered the delineation of tumour volumes when compared to CT alone, and should be considered standard for treatment planning. Although clinical outcomes were not improved with PET/ CT planning, it did allow the use of smaller radiotherapy volumes.
The application of alkyl and aryl substituted cyanamides in synthetic chemistry has diversified m... more The application of alkyl and aryl substituted cyanamides in synthetic chemistry has diversified multi-fold in recent years. In this review, we discuss recent advances (since 2012) in the chemistry of cyanamides and detail their application in cycloaddition chemistry, aminocyanation reactions, as well as electrophilic cyanide-transfer agents and their unique radical and coordination chemistry.
Background-Chronic anticoagulation has been demonstrated to be a risk factor for GI bleeding (GIB... more Background-Chronic anticoagulation has been demonstrated to be a risk factor for GI bleeding (GIB) in patients undergoing endoscopic procedures. Objective-The aim of this study was to determine the incidence of GIB prospectively in a large cohort of patients enrolled in the Clinical Outcomes Research Initiative (CORI) database. Design-Anticoagulated patients undergoing endoscopic procedures were interviewed by phone 30 to 45 days after the procedure to determine potential adverse events and management of warfarin therapy in the perien-doscopic period.
BACKGROUND-The relationship between diabetes, GERD symptoms and acid-related mucosal damage has n... more BACKGROUND-The relationship between diabetes, GERD symptoms and acid-related mucosal damage has not been well studied. AIMS-To better quantify risk of acid-related mucosal damage among patients with and without diabetes. METHODS-A prospective study using 10 sites from the Clinical Outcomes Research Initiative (CORI) National Endoscopy Database surveyed patients undergoing EGD by telephone within 30 days on medical history, symptoms and demographics. Varices and feeding tube indications were excluded. Acid-related damage was defined as any of these findings recorded in CORI: Barrett's esophagus; esophageal inflammation (unless non-acid-related etiology); healed ulcer, duodenal, gastric or esophageal ulcer; stricture; and mucosal abnormality with erosion or ulcer. RESULTS-Of 1569 patients, 16% had diabetes, 95% being type 2. Diabetic patients were significantly more likely to be male, older and have a higher body mass index, and less likely to report frequent heartburn and non-steroidal anti-inflammatory drug use. No significant differences were found in acid reflux and proton pump inhibitor (PPI) use between groups. In unadjusted analyses, diabetic patients had a similar risk for acid-related damage than non-diabetic patients (OR 1.09; 95% CI: 0.83, 1.42) which persisted after adjusting for gender, age, acid reflux, acid indication and PPI use (OR 1.04; 95% CI:0.79, 1.39). CONCLUSIONS-No difference in risk of acid-related mucosal damage was found, even after adjustment for potential confounders. Our data do not support the need for a lower threshold to perform endoscopy in diabetic patients.
Background: The kidneys are a principal dose-limiting organ in radiotherapy for upper abdominal c... more 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. Our current understanding of kidney dose response and tolerance is limited and this is hindering efforts to introduce advanced radiotherapy techniques for upper-abdominal cancers, such as intensity-modulated radiotherapy (IMRT). The aim of this study is to utilise radiotherapy and combined anatomical/functional imaging data to allow direct correlation of radiation dose with spatio-temporal changes in kidney function. The data can then be used to develop a more precise dose-volume response model which has the potential to optimise and individualise upper abdominal radiotherapy plans. 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 51 Cr-ethylenediamine tetra-acetic acid (EDTA) clearance; and a regional kidney perfusion measurement assessing renal uptake of 99m Tc-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.
Clinical and Translational Radiation Oncology, 2017
Background: This prospective study aims to determine the impact of PET/CT on radiotherapy plannin... more Background: This prospective study aims to determine the impact of PET/CT on radiotherapy planning and outcomes in patients with oesophageal cancer. Methods: All patients underwent PET/CT scanning in the radiotherapy treatment position, and received treatment planned using the PET/CT dataset. GTV was defined separately on PET/CT (GTV-PET) and CT (GTV-CT) datasets. A corresponding PTV was generated for each patient. Volumetric and spatial analysis quantified the proportion of FDG-avid disease not included in CT-based volumes. Clinical data was collected to determine locoregional control and overall survival rates. Results: 13 (24.1%) of 57 accrued patients had metastatic disease detected on PET. Median follow up was 4 years. FDG-avid disease would have been excluded from GTV-CT in 29 of 38 patients (76%). In 5 patients, FDG-avid disease would have been completely excluded from the PTV-CT. GTV-CT underestimated the cranial and caudal extent of FDG-avid tumour in 14 (36%) and 10 (26%) patients. 4-Year overall survival and locoregional failure free survival were 37% and 65%. Conclusions: PET/CT altered the delineation of tumour volumes when compared to CT alone, and should be considered standard for treatment planning. Although clinical outcomes were not improved with PET/ CT planning, it did allow the use of smaller radiotherapy volumes.
The application of alkyl and aryl substituted cyanamides in synthetic chemistry has diversified m... more The application of alkyl and aryl substituted cyanamides in synthetic chemistry has diversified multi-fold in recent years. In this review, we discuss recent advances (since 2012) in the chemistry of cyanamides and detail their application in cycloaddition chemistry, aminocyanation reactions, as well as electrophilic cyanide-transfer agents and their unique radical and coordination chemistry.
Background-Chronic anticoagulation has been demonstrated to be a risk factor for GI bleeding (GIB... more Background-Chronic anticoagulation has been demonstrated to be a risk factor for GI bleeding (GIB) in patients undergoing endoscopic procedures. Objective-The aim of this study was to determine the incidence of GIB prospectively in a large cohort of patients enrolled in the Clinical Outcomes Research Initiative (CORI) database. Design-Anticoagulated patients undergoing endoscopic procedures were interviewed by phone 30 to 45 days after the procedure to determine potential adverse events and management of warfarin therapy in the perien-doscopic period.
BACKGROUND-The relationship between diabetes, GERD symptoms and acid-related mucosal damage has n... more BACKGROUND-The relationship between diabetes, GERD symptoms and acid-related mucosal damage has not been well studied. AIMS-To better quantify risk of acid-related mucosal damage among patients with and without diabetes. METHODS-A prospective study using 10 sites from the Clinical Outcomes Research Initiative (CORI) National Endoscopy Database surveyed patients undergoing EGD by telephone within 30 days on medical history, symptoms and demographics. Varices and feeding tube indications were excluded. Acid-related damage was defined as any of these findings recorded in CORI: Barrett's esophagus; esophageal inflammation (unless non-acid-related etiology); healed ulcer, duodenal, gastric or esophageal ulcer; stricture; and mucosal abnormality with erosion or ulcer. RESULTS-Of 1569 patients, 16% had diabetes, 95% being type 2. Diabetic patients were significantly more likely to be male, older and have a higher body mass index, and less likely to report frequent heartburn and non-steroidal anti-inflammatory drug use. No significant differences were found in acid reflux and proton pump inhibitor (PPI) use between groups. In unadjusted analyses, diabetic patients had a similar risk for acid-related damage than non-diabetic patients (OR 1.09; 95% CI: 0.83, 1.42) which persisted after adjusting for gender, age, acid reflux, acid indication and PPI use (OR 1.04; 95% CI:0.79, 1.39). CONCLUSIONS-No difference in risk of acid-related mucosal damage was found, even after adjustment for potential confounders. Our data do not support the need for a lower threshold to perform endoscopy in diabetic patients.
Background: The kidneys are a principal dose-limiting organ in radiotherapy for upper abdominal c... more 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. Our current understanding of kidney dose response and tolerance is limited and this is hindering efforts to introduce advanced radiotherapy techniques for upper-abdominal cancers, such as intensity-modulated radiotherapy (IMRT). The aim of this study is to utilise radiotherapy and combined anatomical/functional imaging data to allow direct correlation of radiation dose with spatio-temporal changes in kidney function. The data can then be used to develop a more precise dose-volume response model which has the potential to optimise and individualise upper abdominal radiotherapy plans. 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 51 Cr-ethylenediamine tetra-acetic acid (EDTA) clearance; and a regional kidney perfusion measurement assessing renal uptake of 99m Tc-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.
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