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Trinh L.,University of Alberta | Plotnikoff R.C.,University of Newcastle | Rhodes R.E.,University of Victoria | North S.,11560 University Ave | Courneya K.S.,University of Alberta
International Journal of Behavioral Nutrition and Physical Activity | Year: 2012

Background: Over half of kidney cancer survivors (KCS) are completely inactive and only a quarter are meeting physical activity (PA) guidelines. This highlights the need to identify and understand the determinants of PA in this understudied population. The purpose of this study is to determine the social cognitive correlates of PA intention and behavior in KCS using the Theory of Planned Behavior (TPB).Methods: All 1,985 KCS diagnosed between 1996 and 2010 in Alberta, Canada were mailed a self-report survey that consisted of the Godin Leisure Time Exercise Questionnaire and standard TPB items for intention, planning, perceived behavioral control (PBC), affective and instrumental attitudes, and descriptive and injunctive norms. Standard demographic and medical variables were also collected.Results: Completed surveys were received from 703 of 1,654 (43%) eligible KCS. The TPB was tested using structural equation modelling and demonstrated an adequate-to-good fit to the data [χ2 = 256.88, p < .001; TLI = 0.97; CFI = 0.98; RMSEA = 0.06, 90% CI = 0.05-0.06].There were significant pathways to PA from PBC (ß = 0.18, p = 0.02), planning (ß = 0.22, p < 0.01), and intention (ß = 0.31, p < 0.01); and to planning from intention (ß = 0.81, p < 0.01). In addition, there were significant model pathways to intention from instrumental attitude (ß = 0.28, p = 0.03), descriptive norm (ß = 0.09, p = 0.01), and PBC (ß = 0.52, p < 0.01). Overall, the TPB accounted for 69%, 63%, and 42% of the variance in intention, planning and PA, respectively.Conclusion: The TPB appears to be a useful model for explaining PA in KCS. All TPB constructs except injunctive norm and affective attitude were useful for explaining intention with PBC emerging as the largest correlate. Developing PA interventions based on the TPB may be effective in promoting PA in KCS and may lead to important improvements in health. © 2012 Trinh et al.; licensee BioMed Central Ltd.


Trinh L.,University of Alberta | Plotnikoff R.C.,University of Alberta | Plotnikoff R.C.,University of Newcastle | Rhodes R.E.,University of Victoria | And 2 more authors.
Mental Health and Physical Activity | Year: 2013

Background: Adverse health effects of sedentary behaviour on cancer risk and health outcomes in cancer survivors have been reported but few studies have examined quality of life (QoL) and no study has focused on kidney cancer survivors (KCS). The purpose of this study was to estimate the prevalence of sitting time among KCS and to determine any associations with QoL. Methods: All 1985 KCS diagnosed between 1996 and 2010 identified through a Canadian provincial Registry were mailed a survey that consisted of the modified domain-specific sitting time questionnaire, the Godin Leisure Time Exercise Questionnaire and several Functional Assessment of Cancer Therapy (FACT) QoL scales. Standard demographic and medical variables were also reported. Results: Completed surveys were received from 540 KCS. The mean hours of sitting time were 8.0 ± 4.7 for a work-day and 6.5 ± 3.8 for a non-work day. After adjustment for key covariates, analyses of covariance indicated that the only significant relationship was an unexpected positive association between sitting time on a work day and emotional well-being (p = 0.019). Moreover, the only variable to moderate these associations was age, with younger KCS under age 60 showing the expected negative associations between sitting time and physical and functional aspects of QoL. Conclusion: KCS sit for a significant amount of time on work days and non-work days, however, there were few associations with QoL. Future observational studies and randomized controlled trials are warranted to examine sitting time and health outcomes among KCS. Crown Copyright © 2012 Published by Elsevier Ltd. All rights reserved.


Yee D.,11560 University Ave | Rathee S.,Cross Cancer Institute | Robinson D.,Cross Cancer Institute | Murray B.,Cross Cancer Institute
International Journal of Radiation Oncology Biology Physics | Year: 2011

Purpose: Small-cell lung cancer is considered to be relatively chemosensitive and radiosensitive. Small-cell tumor volume changes during concurrent chemoradiotherapy have not been quantified. The purpose of this work is to quantify small-cell lung tumor volume variations in limited-stage patients undergoing chemoradiotherapy. Methods and Materials: Eligible patients had pathologically confirmed limited-stage small-cell lung cancer, underwent concurrent chemoradiotherapy, and signed study-specific consent forms. Patients underwent serial chest computed tomography (CT) scans on a CT simulator with images acquired at the same phase of patients' respiratory cycle. Computed tomography scans were obtained at the time of planning CT scan and 3 times a week during radiotherapy (RT). Gross tumor volumes (GTVs) were contoured on each CT scan. Gross tumor volumes defined on each CT scan were analyzed for volume changes relative to pre-RT scans. Results: We obtained 104 CT scans (median, 11.5 scans per patient). The median tumor dose was 50 Gy. The median pre-RT GTV was 98.9 cm 3 (range, 57.8-412.4 cm 3). The median GTV at the final serial CT scan was 10.0 cm 3 (range, 4.2-81.6 cm 3). The mean GTV relative to pre-RT volume at the end of each RT week was 53.0% for Week 1, 29.8% for Week 2, 22.9% for Week 3, 19.5% for Week 4, and 12.4% for Week 5. Conclusions: Dramatic shrinkage of small-cell lung tumors occurred in patients undergoing chemoradiotherapy in this trial. Most of the observed GTV shrinkage occurred during the first week of RT. © 2011 Elsevier Inc.


Fairchild A.,11560 University Ave | Straube W.,Imaged Guided Therapy Center | Laurie F.,Review Centre | Followill D.,University of Houston
International Journal of Radiation Oncology Biology Physics | Year: 2013

Central review of radiation therapy (RT) delivery within multicenter clinical trials was initiated in the early 1970s in the United States. Early quality assurance publications often focused on metrics related to process, logistics, and timing. Our objective was to review the available evidence supporting correlation of RT quality with clinical outcomes within cooperative group trials. A MEDLINE search was performed to identify multicenter studies that described central subjective assessment of RT protocol compliance (quality). Data abstracted included method of central review, definition of deviations, and clinical outcomes. Seventeen multicenter studies (1980-2012) were identified, plus one Patterns of Care Study. Disease sites were hematologic, head and neck, lung, breast, and pancreas. Between 0 and 97% of treatment plans received an overall grade of acceptable. In 7 trials, failure rates were significantly higher after inadequate versus adequate RT. Five of 9 and 2 of 5 trials reported significantly worse overall and progression-free survival after poor-quality RT, respectively. One reported a significant correlation, and 2 reported nonsignificant trends toward increased toxicity with noncompliant RT. Although more data are required, protocol-compliant RT may decrease failure rates and increase overall survival and likely contributes to the ability of collected data to answer the central trial question. © 2013 Elsevier Inc.


Skarsgard D.,University of Calgary | Cadman P.,Saskatoon Cancer Center | El-Gayed A.,Saskatoon Cancer Center | Pearcey R.,11560 University Ave | And 3 more authors.
Radiation Oncology | Year: 2010

Background: Fiducial markers and daily electronic portal imaging (EPI) can reduce the risk of geographic miss in prostate cancer radiotherapy. The purpose of this study was to estimate CTV to PTV margin requirements, without and with the use of this image guidance strategy.Methods: 46 patients underwent placement of 3 radio-opaque fiducial markers prior to prostate RT. Daily pre-treatment EPIs were taken, and isocenter placement errors were corrected if they were ≥ 3 mm along the left-right or superior-inferior axes, and/or ≥ 2 mm along the anterior-posterior axis. During-treatment EPIs were then obtained to estimate intra-fraction motion.Results: Without image guidance, margins of 0.57 cm, 0.79 cm and 0.77 cm, along the left-right, superior-inferior and anterior-posterior axes respectively, are required to give 95% probability of complete CTV coverage each day. With the above image guidance strategy, these margins can be reduced to 0.36 cm, 0.37 cm and 0.37 cm respectively. Correction of all isocenter placement errors, regardless of size, would permit minimal additional reduction in margins.Conclusions: Image guidance, using implanted fiducial markers and daily EPI, permits the use of narrower PTV margins without compromising coverage of the target, in the radiotherapy of prostate cancer. © 2010 Skarsgard et al; licensee BioMed Central Ltd.


Troitskaia A.,University of Alberta | Fallone B.G.,University of Alberta | Fallone B.G.,11560 University Ave | Yahya A.,University of Alberta | Yahya A.,11560 University Ave
Journal of Magnetic Resonance Imaging | Year: 2013

Purpose: To examine the behavior of lipid olefinic and diallylic resonances as a function of PRESS (point resolved spectroscopy) echo time (TE) to determine an optimal long TE value for their measurement at 3 T. Materials and Methods: Experiments were conducted on nine oils (almond, canola, cod liver, corn, linseed, peanut, sesame, sunflower, and walnut oil) and on vertebral and tibial bone marrow in vivo at 3 T. The methylene (or methyl + methylene), diallylic, and olefinic resonances were measured with PRESS with multiple TEs. Results: J-coupling evolution effects on the olefinic and diallylic peaks appeared to be minimized when TE = 200 msec. The TE = 200 msec olefinic/methylene and diallylic/methylene peak area ratios calculated for each oil correlated well with ratios deduced from oil compositions in the literature (R2 = 0.92 and 0.98 for the olefinic and diallylic protons, respectively). In addition, the relative amounts of bone marrow unsaturation of vertebral and tibial bone marrow inferred from the TE = 200 msec olefinic/(methyl + methylene) peak area ratio agreed with values estimated from the literature. Conclusion: A PRESS sequence with a long TE value of 200 msec is suitable for determining relative amounts of lipid unsaturation at 3 T. © 2012 Wiley Periodicals, Inc.


Valdez B.C.,University of Houston | Valdez B.C.,University of Texas M. D. Anderson Cancer Center | Li Y.,University of Houston | Murray D.,11560 University Ave | And 2 more authors.
Biochemical Pharmacology | Year: 2011

DNA alkylating agents alone or with ionizing radiation have been the preferred conditioning treatment in allogeneic hematopoietic stem cell transplantation (allo-HSCT). In search of less toxic alternatives, we hypothesized that combination of busulfan (Bu), fludarabine (Flu) and clofarabine (Clo) would provide superior efficacy. At low concentrations, these drugs show synergistic cytotoxicity in Bu-resistant AML KBM3/Bu2506 cells. Similar molecular responses were observed in other AML cell lines and in primary explanted AML cells. The [Clo + Flu + Bu] combination activates an intense DNA damage response through the ATM pathway, leading to cell cycle checkpoint activation and apoptosis. Phosphorylations of SMC1 and SMC3, and methylations of histones 3 and 4, are much more pronounced in cells exposed to [Clo + Flu + Bu] than [Clo + Flu], suggesting their relevance in the efficacy of the triple-drug combination. A possible mechanism for these observed synergistic effects involves the capability of [Clo + Flu] to induce histone methylations and subsequent chromatin remodeling, which may render the genomic DNA more accessible to Bu alkylation. The Bu-mediated DNA cross-linking may provide a feedback loop which perpetuates the DNA damage response initiated by [Clo + Flu] and commits the cells to apoptosis. Our results provide a conceptual mechanistic basis for exploring this triple-drug combination in pretransplant conditioning therapy for allo-HSCT.


Yahya A.,11560 University Ave | Yahya A.,University of Alberta | Tessier A.G.,11560 University Ave | Fallone B.G.,11560 University Ave | Fallone B.G.,University of Alberta
Journal of Magnetic Resonance Imaging | Year: 2011

Purpose: To demonstrate, at 9.4 T, that J-coupling interactions exhibited by lipid protons affects lipid composition determination with a point resolved spectroscopy (PRESS) sequence. Materials and Methods: Experiments were conducted on four oils (almond, corn, sesame, and sunflower), on visceral adipose tissue of a euthanized mouse, and on pure linoleic acid at 9.4 T. The 2.1, 2.3, and 2.8 ppm resonances were measured at multiple echo times (TEs) by a standard PRESS sequence and by a PRESS sequence consisting of narrow-bandwidth refocusing pulses designed to rewind the J-coupling evolution of the target peak protons in the voxel of interest. T2 corrections were performed on both groups of data for the three peaks and lipid compositions for the oils and for the mouse tissue were determined. Lipid compositions were also calculated from a short-TE standard PRESS spectrum. Results: A chemical analysis of the samples was not performed; however, the oil compositions calculated from resonance peaks acquired with the PRESS sequence designed to minimize J-coupling effects, following T2 relaxation correction, closely agreed with values in the literature, which was not the case for all of the compositions determined from the regular PRESS spectra. Conclusion: The presented work brings to attention the significance of J-coupling effects when calculating lipid compositions from localized proton spectra. Copyright © 2011 Wiley Periodicals, Inc.


Fairchild A.,11560 University Ave | Ghosh S.,11560 University Ave
Canadian Family Physician | Year: 2012

Objective: To assess practitioners' referral patterns and knowledge of palliative radiotherapy (PRT). Design: A 23-item questionnaire. Setting: Northern Alberta and parts of British Columbia, Saskatchewan, the Northwest Territories, and Nunavut. Participants: A total of 1360 health practitioners, including primary care physicians and nurse clinicians in rural, remote, or far northern regions; FP-oncologists working in community cancer centres; palliative care (PC) specialists; and medical oncologists. Main outcome measures: Survey respondents rated how much certain factors influenced their decisions to refer patients for PRT and estimated their knowledge of PRT. Descriptive and summary statistics were compiled. Results: The overall eligible response rate was 31.8% (412 of 1294); 85.4% of respondents were FPs, 65.3% were men, and 44.9% practised in rural settings. A total of 81.8% of respondents sometimes or often provided PC and 71.0% had referred patients for PRT. Main factors taken into account when referring patients were functional status (93.1%; 349 of 375), histology (75.4%; 285 of 378), and concern about side effects (75.3%; 281 of 373). Half of respondents considered wait times for PRT delivery important. Self-rated knowledge of PRT was poor for 74.0% of respondents, fair for 24.5%, and good for 1.5%. Actual knowledge scores were poor for 46.6% of respondents, fair for 36.7%, and good for 16.7%. Respondents who referred patients for PRT had been in practice longer, saw more cancer patients per month, provided PC more frequently, had higher self-rated PRT knowledge, and had better actual PRT knowledge. Conclusion: Disease- and patient-related factors outweighed concerns about wait times. Although referring practitioners are better informed than they believe themselves to be, further improvements in their knowledge could increase referrals of appropriate patients for PRT.


Makis W.,11560 University Ave | Kurzencwyg D.,McGill University | Hickeson M.,McGill University
Clinical Imaging | Year: 2013

The aim of this study was to examine whether positron emission tomography (PET)/computed tomography (CT) can detect more cases of colorectal cancer (CRC) than serum carcinoembryonic antigen (CEA), both at initial staging and during surveillance for recurrence. A retrospective review of 639 CRC patients imaged with PET/CT was performed. PET/CT was superior to serum CEA in detecting CRC, identifying 2.5 times as many CRC at initial staging compared to serum CEA and 1.5 times as many CRC recurrences. The current guideline recommendations of utilizing PET/CT only in the context of a rising serum CEA will miss more than one third of all CRC recurrences. © 2013 Elsevier Inc.

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