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Featured researches published by Shilo Lefresne.


International Journal of Radiation Oncology Biology Physics | 2013

Impact of Quality Assurance Rounds in a Canadian Radiation Therapy Department

Shilo Lefresne; Ivo A. Olivotto; Howard Joe; Paul Blood; Robert Olson

PURPOSE Quality assurance (QA) programs aim to identify inconsistencies that may compromise patient care. Radiation treatment planning is a well-documented source of variation in radiation oncology, leading many organizations to recommend the implementation of QA rounds in which radiation therapy plans are peer reviewed. This study evaluates the outcome of QA rounds that have been conducted by a radiation therapy department since 2004. METHODS AND MATERIALS Prospectively documented records of QA rounds, from 2004 to 2010, were obtained. During rounds, randomly selected radiation therapy plans were peer reviewed and assigned a grade of A (adequate), B (minor suggestions of change to a plan for a future patient), or C (significant change required before the next fraction). The proportion of plans that received each recommendation was calculated, and the relationship between recommendations for each plan, tumor site, and mean years of experience of the radiation oncologist (RO) were explored. Chart reviews were performed for each plan that received a C. RESULTS During the study period, 1247 plans were evaluated; 6% received a B and 1% received a C. The mean RO years of experience were lower for plans graded C versus those graded A (P=.02). The tumor sites with the highest proportion of plans graded B or C were gastrointestinal (14%), lung (13%), and lymphoma (8%). The most common reasons for plans to receive a grade of C were inadequate target volume coverage (36%), suboptimal dose or fractionation (27%), errors in patient setup (27%), and overtreatment of normal tissue (9%). CONCLUSIONS This study demonstrated that QA rounds are feasible and an important element of a radiation therapy departments QA program. Through peer review, plans that deviate from a departments expected standard can be identified and corrected. Additional benefits include identifying patterns of practice that may contribute to inconsistencies in treatment planning and the continuing education of staff members who attend.


Cuaj-canadian Urological Association Journal | 2012

Genitourinary malignancy presenting as an ocular metastasis: A case report and review of the literature

Shilo Lefresne; Alysa Fairchild; Royce Johnson; Jean Deschenes; Laurie Russell; John Pederson

Metastases to the eye or orbit as the initial presentation of genitourinary malignancy are unusual and can be a diagnostic challenge. We report an 81-year-old man who presented with pain and proptosis in an eye that had been blind for 50 years. Radiologic investigations identified a mass involving the left globe and orbit. Histology of the enucleation specimen was consistent with a metastatic poorly differentiated carcinoma suggestive of a prostate primary. With the constellation of obstructive urinary symptoms, an abnormal digital rectal examination, elevated prostate-specific antigen and a positive bone scan, androgen deprivation therapy was initiated for metastatic prostate cancer. After an initial response to treatment, the patients disease progressed in a manner atypical for prostate cancer. After describing our case, we review the literature on ocular and orbital metastases and their relation to genitourinary malignancies.


Journal of Rural Health | 2017

Impact of Travel Distance and Urban‐Rural Status on the Multidisciplinary Management of Rectal Cancer

Jonathan M. Loree; Khodadad Rasool Javaheri; Shilo Lefresne; Caroline Speers; Jenny Y. Ruan; Jennifer T. Chang; Carl J. Brown; Hagen F. Kennecke; Robert Olson; Winson Y. Cheung

OBJECTIVES Optimal treatment of rectal cancer (RC) requires multidisciplinary care. We examined whether distance to treatment center or community size impacts access to multimodality care and population-based outcomes in RC. METHODS Patients diagnosed with stage II/III RC from 1999 to 2009 and treated at 1 of 6 regional cancer centers in British Columbia were reviewed. Distance to treatment center was determined for each patient. Communities were classified as rural, small, medium, and large population centers. Logistic and Cox regression models assessed associations of distance and community size with treatment received as well as cancer-specific (CSS) and overall survival (OS). RESULTS Of 3,158 patients, 93.6% underwent surgery, 86.3% received radiotherapy, and 51.3% were treated with adjuvant chemotherapy (AC). Median time from diagnosis to oncologic consultation was longer for those >100 km from a treatment center or residing in medium/rural communities. Logistic regression demonstrated no correlation between distance or community size and receipt of treatment modality. Univariate analysis showed similar CSS (P = .18, .88) and OS (P = .36, .47) based on community size and distance, respectively. In multivariate analysis, distance >100 km had inferior CSS (Hazard Ratio [HR] 1.39, 95% CI: 1.03-1.88; P = .031). There was no consistent trend between decreasing community size and outcomes; however, living in a small center was associated with improved OS (HR 0.58, 95% CI: 0.38-0.88; P = .011) and CSS (HR 0.42, 95% CI: 0.25-0.70; P = .001). CONCLUSIONS In this population-based study, there were no urban-rural differences in access to multidisciplinary care, but increased distance may be associated with worse cancer-specific outcomes.


International Journal of Radiation Oncology Biology Physics | 2015

Delayed Workforce Entry and High Emigration Rates for Recent Canadian Radiation Oncology Graduates

Shaun K. Loewen; Ross Halperin; Shilo Lefresne; Theresa Trotter; Teri Stuckless; Michael Brundage

PURPOSE To determine the employment status and location of recent Canadian radiation oncology (RO) graduates and to identify current workforce entry trends. METHODS AND MATERIALS A fill-in-the-blank spreadsheet was distributed to all RO program directors in December 2013 and June 2014, requesting the employment status and location of their graduates over the last 3 years. Visa trainee graduates were excluded. RESULTS Response rate from program directors was 100% for both survey administrations. Of 101 graduates identified, 99 (98%) had known employment status and location. In the December survey, 5 2013 graduates (16%), 17 2012 graduates (59%), and 18 2011 graduates (75%) had permanent staff employment. Six months later, 5 2014 graduates (29%), 15 2013 graduates (48%), 24 2012 graduates (83%), and 21 2011 graduates (88%) had secured staff positions. Fellowships and temporary locums were common for those without staff employment. The proportion of graduates with staff positions abroad increased from 22% to 26% 6 months later. CONCLUSIONS Workforce entry for most RO graduates was delayed but showed steady improvement with longer time after graduation. High emigration rates for jobs abroad signify domestic employment challenges for newly certified, Canadian-trained radiation oncologists. Coordination on a national level is required to address and regulate radiation oncologist supply and demand disequilibrium in Canada.


Advances in radiation oncology | 2017

Estimating prognosis at the time of repeat whole brain radiation therapy for multiple brain metastases: The reirradiation score

N. Logie; R.B. Jimenez; Natalie Pulenzas; Kelly Linden; Denise Ciafone; Sunita Ghosh; Yuhui Xu; Shilo Lefresne; Erin Wong; Christina H. Son; Helen A. Shih; William W. Wong; Scott Tyldesley; Kristopher Dennis; Edward Chow; Alysa Fairchild

Purpose Whole brain radiation therapy (WBRT) remains the standard of care for patients with multiple brain metastases, but more than half of treated patients will develop intracranial progression. Because there is no clear consensus on the optimal therapeutic approach, a prognostic index would be helpful to guide treatment options at progression. We explored whether the recursive partitioning analysis (RPA) score prior to repeat WBRT is predictive of survival. Methods and materials This multi-institutional pooled analysis included patients with 2 or more brain metastases from any solid primary tumor that was treated with 2 courses of WBRT. Information on demographics, disease characteristics, and intervals between courses was collected. RPA class was abstracted or retrospectively assigned, and descriptive statistics calculated. Median survival (MS) was determined using the Kaplan-Meier method and compared using log rank tests. Univariate and multivariate analyses were performed via Cox regression analysis. Results For 205 patients, the median age was 55 years (range, 25-83 years), 68% were female, 40.5% had non-small cell lung cancer, and 31.2% had small cell lung cancer. Prior to the second WBRT, 4.9% of patients were RPA class 1, 36.6% were RPA2, and 58.5% were RPA3, with an MS of 7.5 months (95% confidence interval [CI], 4.7-10.3), 5.2 months (95% CI, 3.7-6.7 months), and 2.9 months (95% CI, 2.2-2.9 months), respectively (P = .001). On univariate and multivariate analyses, a Karnofsky Performance Status of <80, extracranial metastases, interval between courses <9 months, small cell lung cancer histology, and uncontrolled primary significantly correlated with shorter MS. By assigning a score of 1 to each of these factors, a new prognostic index was created, the reirradiation (ReRT) score. Survival on the basis of ReRT score grouping ranged from 2.2 to 7.2 months and demonstrated significant differences in MS. Conclusions In the largest reported cohort to receive repeat WBRT, application of the RPA score was not predictive of MS. The new ReRT score is a simple tool based on readily available clinical information.


International Journal of Radiation Oncology Biology Physics | 2018

Programmatic Comparison and Dissemination of an Audit of Single-fraction Radiation Therapy Prescribing Practices for Bone Metastases is Associated with a Meaningful and Lasting Change in Practice on a Population Level

Robert Olson; Matthew W. C. Chan; Neelam Minhas; Gurkirat Kandola; Manpreet S. Tiwana; Shilo Lefresne; Ross Halperin; Devin Schellenberg; Elaine Wai; Nissar Ahmed; Scott Tyldesley

PURPOSE There is ample evidence that single-fraction radiation therapy (SFRT) is as efficacious as more costly and morbid multifraction regimens. We previously demonstrated that an audit-based intervention increased the use of SFRT in all regional cancer centers the following year. However, other investigators have demonstrated that interventions were only associated with a transient 1-year change in prescribing practices. We sought to determine whether our intervention resulted in a more lasting impact. METHODS AND MATERIALS In 2012, we performed an audit of the prescribing practices of individual physicians, which was then presented to leaders and oncologists as an intervention to increase SFRT. We compared the use of SFRT between 2007 to 2011 (preintervention) and 2013 to 2016 (postintervention) in all 31,192 patients treated in our provincial program. RESULTS The use of SFRT increased from 49.2% to 58.9% postintervention (P < .001). Rates from 2007 to 2011 were 51%, 51%, 48%, 49%, and 48%, respectively, whereas the postintervention rates from 2013 to 2016 were 60%, 62%, 59%, and 56%, respectively. Postintervention, half of the centers prescribed SFRT in a relatively narrow range (55%-58%). However, across all centers, there was still a broad range, with the lowest and highest users at 35% and 81%, respectively, although the lowest-using center still showed a significant increase (26% to 35%; P < .001). CONCLUSIONS Our audit and education-based intervention resulted in a lasting and meaningful 10% change in practice. Our provincial rate is similar to that of a previously recommended benchmark rate of 60%, but we continue to see significant variation by center, suggesting further room for improvement in provincial standardization. With emerging evidence in support of ablative radiation therapy for select populations of patients with bone metastases, future benchmark rates of SFRT should be readdressed. However, our data suggest that programmatic comparison and dissemination of SFRT prescribing practices can achieve a population-based SFRT utilization rate near 60%.


Lung Cancer | 2017

Prospective analysis of patient reported symptoms and quality of life in patients with incurable lung cancer treated in a rapid access clinic

Shilo Lefresne; Robert Olson; Rosemary Cashman; Paula Kostuik; Wei Ning Jiang; Karen Levy; Michael R. McKenzie; Ann Hulstyn; Mitchell Liu; Jonn Wu; Eric Berthelet

INTRODUCTION The Vancouver Rapid Access (VARA) clinic was designed to provide palliative radiotherapy and holistic care to patients with incurable lung cancer. Analysis of the pilot phase demonstrated improved radiotherapy wait-times and access to supportive services compared to standard practice. This study aims to prospectively assess the impact of the clinic on patient reported symptoms and quality of life. MATERIALS AND METHODS Patient assessments are completed at baseline and by a telephone follow up four-weeks later using Likert scales adapted from the Edmonton Symptom Assessment System (scale 0-10) and European Organization for Research and Treatment of Cancer questionnaires (scale 1-4). Patient reported outcomes at follow-up are compared to baseline using wilcoxon signed-rank test for categorical variables and paired sample t-test for continuous variables. RESULTS Baseline data was collected on 125 patients, 109 received palliative radiotherapy (87%). At the 4 week follow up, 22 patients had died. Seventy-one of the remaining 103 patients completed the follow-up questionnaire, resulting in a 69% response rate among survivors. The mean patient reported overall health score, improved from 4.8 to 6.1 (p<0.01). All respiratory symptoms except chest pain (p=0.06) were associated with a statistically significant improvement after the clinic, whereas all respiratory symptoms improved post radiotherapy. Mean bone pain scores decreased from 5.5 to 2.7 (p<0.01). Assessment of symptoms secondary to brain metastases is limited by small patient numbers. CONCLUSION The VARA clinic provides timely access to palliative radiotherapy and supportive services resulting in improved patient reported outcomes. Despite a high symptom and disease burden, patients report improved overall health and palliation of respiratory symptoms and bony pain. The studies completed on the VARA clinic to date, continue to support its value in our center.


Journal of Clinical Oncology | 2016

Patterns of radiation therapy technology use in the treatment of bone metastases.

Matthew H. Chan; Robert Olson; Shilo Lefresne; Michael R. McKenzie

211 Background: In recent years, there has been a transition from two-dimensional radiation therapy (2DRT) planning towards more advanced techniques such as three-dimensional conformal radiation therapy (3D-CRT), volumetric modulated arc therapy (VMAT), and stereotactic body radiation therapy (SBRT). Our study aim was to analyze these trends in the treatment of bone metastases. METHODS All patients aged 18 and older who had received palliative intent RT for bone metastases between 2009-2014 and referred to any 1 of 6 regional cancer centers in British Columbia, Canada were reviewed. Summary statistics were used to describe radiation technique patterns. Logistic regression modeling was used to assess the influence of demographic, clinical, and health services variables on receipt of types of RT. RESULTS We identified 8,059 patients and 15,832 courses of RT; overall, 97.9% of courses were achieved by 2DRT and 2.1% by 3D-CRT, VMAT, or SBRT. Despite the low overall use of advanced techniques, its use was significantly higher in all subsequent years compared to 2009 (p < 0.05 for all years). The median age for patients treated with 2DRT was 67.0 (19-99) versus 66.0 years (19-93) for advanced techniques. There did not appear to be a statistically significant difference in age at the time of treatment start (OR 0.99; 95% CI 0.981-1.00, p < 0.05). Compared to lung cancers, thyroid (OR 9.9; 95% CI 5.197-18.724, p < 0.001) and kidney cancers (OR 3.9; 95% CI 2.508-5.911, p < 0.001) were significantly more likely to be treated with advanced techniques, while breast (OR 0.90; 95% CI 0.621-1.306, p = 0.58) and prostate cancers (OR 0.93; 95% CI 0.613-1.410, p = 0.73) were not any more likely. Compared to the Vancouver center, all other treatment centers in the province were utilizing advanced techniques less frequently. Patients were also more likely to complete RT with 2DRT than with advanced techniques (98.3% versus 95.8%, p < 0.05). CONCLUSIONS The vast majority of treatment of bone metastases is still done by 2DRT in British Columbia. Despite these overall statistics though, a trend towards increasing use of more advanced techniques was observed.


Supportive Care in Cancer | 2015

The Vancouver rapid access clinic for palliative lung radiation, providing more than just rapid access

Shilo Lefresne; Eric Berthelet; Rosemary Cashman; Karen Levy; Mitchel Liu; Hannah Carolan; Michael McKenzie; Paula Kostuik; Robert Olson


International Journal of Radiation Oncology Biology Physics | 2014

Management of Stage II and III Rectal Cancer: Is There a Rural-Urban Difference?

Shilo Lefresne; Winson Y. Cheung; J. Hay; Carl J. Brown; Caroline Speers; Robert Olson

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Robert Olson

University of British Columbia

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Carl J. Brown

University of British Columbia

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Erin Wong

Sunnybrook Health Sciences Centre

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