Ken Schneider
Cancer Care Ontario
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Featured researches published by Ken Schneider.
The New England Journal of Medicine | 2010
Timothy J. Whelan; Jean-Philippe Pignol; Mark N. Levine; Jim A. Julian; Robert MacKenzie; Sameer Parpia; Wendy Shelley; Laval Grimard; Julie Bowen; Francisco Perera; Anthony Fyles; Ken Schneider; Sunil P.P. Gulavita; Carolyn R. Freeman
BACKGROUND The optimal fractionation schedule for whole-breast irradiation after breast-conserving surgery is unknown. METHODS We conducted a study to determine whether a hypofractionated 3-week schedule of whole-breast irradiation is as effective as a 5-week schedule. Women with invasive breast cancer who had undergone breast-conserving surgery and in whom resection margins were clear and axillary lymph nodes were negative were randomly assigned to receive whole-breast irradiation either at a standard dose of 50.0 Gy in 25 fractions over a period of 35 days (the control group) or at a dose of 42.5 Gy in 16 fractions over a period of 22 days (the hypofractionated-radiation group). RESULTS The risk of local recurrence at 10 years was 6.7% among the 612 women assigned to standard irradiation as compared with 6.2% among the 622 women assigned to the hypofractionated regimen (absolute difference, 0.5 percentage points; 95% confidence interval [CI], -2.5 to 3.5). At 10 years, 71.3% of women in the control group as compared with 69.8% of the women in the hypofractionated-radiation group had a good or excellent cosmetic outcome (absolute difference, 1.5 percentage points; 95% CI, -6.9 to 9.8). CONCLUSIONS Ten years after treatment, accelerated, hypofractionated whole-breast irradiation was not inferior to standard radiation treatment in women who had undergone breast-conserving surgery for invasive breast cancer with clear surgical margins and negative axillary nodes. (ClinicalTrials.gov number, NCT00156052.)
Journal of Clinical Epidemiology | 2001
Patti A. Groome; Brian O'Sullivan; Jonathan C. Irish; Deanna Rothwell; Karleen Schulze M. Math; Randy J. Bissett; Peter R. Dixon; Libni J. Eapen; Sunil P.P. Gulavita; J. Alex Hammond; D. Ian Hodson; Robert G. Mackenzie; Ken Schneider; Padraig Warde; William J. Mackillop
We compared the management and outcome of glottic cancer in Ontario, Canada to that in the Surveillance, Epidemiology and End Results (SEER) Program areas in the United States to determine whether the greater use of primary radiotherapy with surgery reserved for salvage in Ontario was associated with similar survival and better larynx retention rates than the U.S. approach where primary surgery is used more often. Electronic, clinical and hospital data were linked to cancer registry data and supplemented by chart review where necessary. Initial treatment and survival in patients diagnosed in the SEER areas from 1988 through 1994 were compared to patients from Ontario diagnosed from 1982 through 1995. Actuarial laryngectomy rates were compared for patients over 65 at diagnosis in the two regions. Analyses were conducted over all cases and stratified by disease stage. In localized disease (T1 or T2), conservative treatment was the most common initial treatment in both regions, although total laryngectomy was used more often in SEER than Ontario (6.2% vs. 0.2%, respectively, P <.001). In advanced disease (T3 or T4), total laryngectomy was more commonly used as initial treatment in SEER (62.9% vs. 21.0% in Ontario, P < or =.001). Over all cases, the relative survival rate was 80% in Ontario at 5 years compared to 78% in SEER (P =.33). In localized disease, the relative survival rates were 4 to 5% higher in Ontario from the second year on, while in advanced disease 2 to 3% higher rates in SEER did not approach statistical significance. Actuarial laryngectomy rates at 3 years differed between the two regions, with a 4% higher rate in SEER (P =.01). In localized disease, 12.6% of Ontario patients had a laryngectomy by 3 years postdiagnosis compared to 17.9% in SEER (P =.05). In advanced disease, the rates were 63.3% and 79.2%, respectively (P =.07). There are large differences in the management of glottic cancer between the SEER areas of the U.S. and Ontario and no evidence that a policy emphasizing radiotherapy with surgery reserved for salvage is associated with worse survival. Ultimate laryngectomy rates are lower in Ontario for localized disease and may be lower for advanced disease. Conservation treatment should be used for localized disease while the treatment decision in advanced disease may be especially sensitive to patient values for voice retention versus initial cure.
Journal of Clinical Oncology | 2003
Patti A. Groome; Brian O’Sullivan; Jonathan C. Irish; Deanna Rothwell; Karleen Schulze; Padraig Warde; Ken Schneider; Robert MacKenzie; D. Ian Hodson; J. Alex Hammond; Sunil P.P. Gulavita; Libni Eapen; Peter Dixon; Randy J. Bissett; William J. Mackillop
PURPOSE We compared the management and outcome of supraglottic cancer in Ontario, Canada, with that in the Surveillance, Epidemiology, and End Results (SEER) Program areas in the United States. METHODS Electronic, clinical, and hospital data were linked to cancer registry data and supplemented by chart review where necessary. Stage-stratified analyses compared initial treatment and survival in the SEER areas (n = 1,643) with a random sample from Ontario (n = 265). We also compared laryngectomy rates at 3 years in those patients 65 years and older at diagnosis. RESULTS Radical surgery was more commonly used in SEER, with absolute differences increasing with increasing stage: I/II, 17%; III, 36%; and IV, 45%. The 5-year survival rates were 74% in Ontario and 56% in SEER for stage I/II disease (P =.01), 55.7% in Ontario and 46.8% in SEER for stage III disease (P =.40), and 28.5% in Ontario and 29.1% in SEER for stage IV disease (P =.28). Cancer-specific survival results mirrored the overall survival results with the exception of stage IV disease, for which 34.6% of Ontario patients survived their cancer compared with 38.1% in SEER (P =.10). This stage IV difference was more pronounced when we further controlled for possible cause of death errors by restricting the comparison to patients with a single primary cancer (P =.01). Three-year actuarial laryngectomy rates differed. In stage I/II, these rates were 3% in Ontario compared with 35% in SEER (P < 10(-3)). In stage III disease, the rates were 30% and 54%, respectively (P =.03), and in stage IV disease they were 33% and 64% (P =.002). CONCLUSION There are large differences in the management of supraglottic cancer between the SEER areas of the United States and Ontario. Long-term larynx retention was higher in Ontario, where radiotherapy is widely regarded as the treatment of choice and surgery is reserved for salvage. In stages I to III, survival was similar in the two regions despite the differences in treatment policy. In stage IV, there may be a small survival advantage in the U.S. SEER areas related to the higher use of primary surgery.
Cancer | 2001
Lisa Barbera; Patti A. Groome; William J. Mackillop; Karleen Schulze; Brian O'Sullivan; Jonathan C. Irish; Padraig Warde; Ken Schneider; Robert G. Mackenzie; D. Ian Hodson; J. Alex Hammond; Sunil P.P. Gulavita; Libni Eapen; Peter Dixon; Randy J. Bissett
The objectives of this study were 1) to describe patterns of use of computed tomography (CT) in laryngeal carcinoma, and 2) to characterize the contribution of CT to the T classification of laryngeal carcinoma.
Journal of Clinical Epidemiology | 2002
Patti A. Groome; Karleen Schulze; Morten Boysen; Stephen F. Hall; William J. Mackillop; Brian O'Sullivan; J. Irish; Padraig Warde; Ken Schneider; Robert G. Mackenzie; D. Ian Hodson; J. Alex Hammond; Sunil P.P. Gulavita; Libni J. Eapen; P.F. Dixon; Randy J. Bissett
The combination of T, N, and M classifications into stage groupings is meant to facilitate a number of activities including: the estimation of prognosis and the comparison of therapeutic interventions among similar groups of cases. We tested the UICC/AJCC fifth edition stage grouping and six other TNM-based groupings proposed for head and neck cancer for their ability to meet these expectations in laryngeal cancer using data from Ontario, Canada, and the area of Southern Norway surrounding Oslo. We defined four criteria to assess each grouping scheme: (1) the subgroups defined by T, N, and M comprising a given group within a grouping scheme have similar survival rates (hazard consistency); (2) the survival rates differ among the groups (hazard discrimination); (3) the prediction of cure is high (outcome prediction); and (4) the distribution of patients among the groups is balanced. We previously identified or derived a measure for each criterion, and the findings were summarized using a scoring system. The range of scores was from 0 (best) to 7 (worst). The data sets were population-based, with 861 cases from Ontario and 642 cases from Southern Norway. Clinical stage assignment was used and the outcome of interest was cause-specific survival. Summary scores across the seven schemes had similar ranges: 0.9 to 5.1 in Ontario and 1.8 to 5.7 in Southern Norway, but the ranking varied. Summing the scores across the two datasets, the TANIS-7 scheme (Head & Neck 1993;15:497-503) ranked first, and was ranked high in both datasets (first and second, respectively). The UICC/AJCC scheme ranked sixth out of seven schemes, and its ranking was fifth and seventh, respectively. UICC/AJCC stage groupings were defined without empirical investigation. When tested, this scheme did not perform best. Our results suggest that the usefulness of the TNM system could be enhanced by optimizing the design of stage groupings through empirical investigation.
Clinical Oncology | 2011
Patti A. Groome; Brian O’Sullivan; William J. Mackillop; Jonathan C. Irish; Karleen Schulze; L.D. Jackson; Randy J. Bissett; P.F. Dixon; Libni J. Eapen; Sunil P.P. Gulavita; J.A. Hammond; D.I. Hodson; Robert G. Mackenzie; Ken Schneider; Padraig Warde
AIMS We conducted a population-based study of practice patterns and outcome across the regional cancer centres providing care to patients with laryngeal cancer in the Province of Ontario, Canada. MATERIALS AND METHODS : This was a retrospective cohort study of 1547 patients with cancers of the glottic or supraglottic larynx diagnosed between 1982 and 1995. Data were collected via chart review, including: patient and disease characteristics, treatment, waiting times and treatment volumes. Vital status was obtained from the Ontario Cancer Registry. Variations across the nine regional cancer centres are described and their effect on outcome explored. All analyses were stratified by stage I and II separately from stage III and IV. RESULTS Treatments differed across centres (P<0.0001); for instance, in the stage I and II group, use of a daily dose of >2.54Gy varied from 0 to 87.6% and in the stage III and IV group, total laryngectomy rates varied from a low of 6% to a high of 53%. The percentage of patients waiting more than 6 weeks from diagnosis to first treatment varied from 17 to 49% (P<0.0001). Multivariate analysis revealed cause-specific survival differences that were not explained by control for case mix, treatment or waiting times. Differences ranged from an 82% risk reduction in one centre compared with the reference (stage I and II group, P=0.008) to a 153% increase in risk (stage III and IV group, P=0.02). Centre case volumes were not associated with cause-specific survival. CONCLUSIONS This study quantifies the degree of variation that can occur in the treatment and outcome of people with cancer. We cannot properly assess whether care delivery is of high quality until we have a better understanding of the factors that drive such variations.
Clinical Oncology | 2003
L.D. Jackson; Patti A. Groome; Karleen Schulze; Brian O'Sullivan; J. Irish; P.F. Dixon; Libni J. Eapen; S.P Gulavita; J.A. Hammond; D.I. Hodson; Robert G. Mackenzie; R.J Bissett; Ken Schneider; Padraig Warde; William J. Mackillop
AIMS To describe the variation in the delivery of radiation therapy to patients with T1N0 glottic cancer who were diagnosed in Ontario, Canada, between 1982 and 1995. MATERIALS AND METHODS The patient population consisted of a random sample of 461 patients treated with curative intent from the nine cancer centres that administer radiation therapy in the province. Abstracted variables included prescribed dose (Gy) and fractionation (f), beam energy and arrangement, set-up, field size, beam modifiers, positioning and treatment interruptions. RESULTS Thirteen prescribed dose-fractionation schemes (> or = four cases each) were identified, including 50.0-53.0 Gy/20 f (54.5%), 55.0-61.0 Gy/25 f (30.3%), and 60.0-66.0 Gy/30-33 f (7.7%). All regimens used one fraction per day, 5 days per week. An isocentric set-up was used (94.3%), with megavoltage (MV) beam energies of Cobalt-60 (87.9%), 6 MV (6.1%) and 4 MV (6.1%). A lateral parallel-opposed pair of beams was the predominant technique (76.4%) versus an anterior oblique pair (17.2%) or angle-down pair (caudally directed fields to achieve shoulder clearance, 5.7%). Wedging (96.3%) and bolus (11.8%) were used as beam-modifying devices. Predominant field-width dimensions were 5.0-6.0 cm (43.4%) and 6.5-7.0 cm (43.1%), and field length dimensions were 5.0-6.0 cm (49.5%) and 6.5-7.0 cm (35.0%). Head, neck or chin immobilisation was used in 86.9% of the cases, with 94.6% of these being custom-made. We found that radiotherapy practice was stable over time, except for a trend of increasing field size and increasing use of immobilisation. In contrast, we found practice variations among the provinces cancer centres. On the basis of our findings, we defined a predominant technical practice consisting of Cobalt-60 (reflecting machine availability during the period of the study), an isocentric set-up, a lateral parallel-opposed pair technique with wedging, and supine-head neutral positioning with custom immobilisation. Forty-two per cent of the cases had one or more components of treatment that differed from this definition. CONCLUSIONS Description of practice variation can provoke discussion about unrecognised differences in practice policies, perhaps identifying the need for better evidence, treatment guidelines, or both.
International Journal of Radiation Oncology Biology Physics | 2017
Julie Rouette; Eric Gutierrez; Jennifer O'Donnell; Lindsay Elizabeth Reddeman; Margaret Hart; Sophie Foxcroft; Gunita Mitera; Padraig Warde; Michael D. Brundage; Gregory J. Czarnota; Medhat El-Mallah; Conrad Falkson; Fei-Fei Liu; Sunil P.P. Gulavita; William McMillan; Jason R. Pantarotto; Ramana Rachakonda; Nancy Read; Ken Schneider; Sarwat Shehata; Christiaan Stevens; Jonathan Tsao; John Waldron; Woodrow Wells; J. Wright; Michael B. Sharpe; Elizabeth Lockhart; Michael Brundage; Amanda Caissie; Helmut Hollenhorst
PURPOSE To describe the outcomes of peer review across all 14 cancer centers in Ontario. METHODS AND MATERIALS We identified all peer-reviewed, curative treatment plans delivered in Ontario within a 3-month study period from 2013 to 2014 using a provincial cancer treatment database and collected additional data on the peer-review outcomes. RESULTS Considerable variation was found in the proportion of peer-reviewed plans across the centers (average 70.2%, range 40.8%-99.2%). During the study period, 5561 curative plans underwent peer review. Of those, 184 plans (3.3%) had changes recommended. Of the 184 plans, the changes were major (defined as requiring repeat planning or having a major effect on planning or clinical outcomes, or both) in 40.2% and minor in 47.8%. For the remaining 12.0%, data were missing. The proportions of recommended changes varied among disease sites (0.0%-7.0%). The disease sites with the most recommended changes to treatment plans after peer review and with the greatest potential for benefit were the esophagus (7.0%), uterus (6.7%), upper limb (6.3%), cervix and lower limb (both 6.0%), head and neck and bilateral lung (both 5.9%), right supraclavicular lymph nodes (5.7%), rectum (5.3%), and spine (5.0%). Although the heart is an organ at risk in left-sided breast treatment plans, the proportions of recommended changes did not significantly differ between the left breast treatment plans (3.0%, 95% confidence interval 2.0%-4.5%) and right breast treatment plans (2.4%, 95% confidence interval 1.5%-3.8%). The recommended changes were more frequently made when peer review occurred before radiation therapy (3.8%) than during treatment (1.4%-2.8%; P=.0048). The proportion of plans with recommended changes was not significantly associated with patient volume (P=.23), peer-review performance (P=.36), or center academic status (P=.75). CONCLUSIONS Peer review of treatment plans directly affects the quality of care by identifying important clinical and planning changes. Provincial strategies are underway to optimize its conduct in radiation oncology.
International Journal of Radiation Oncology Biology Physics | 2006
Patti A. Groome; Brian O’Sullivan; William J. Mackillop; Lynda D. Jackson; Karleen Schulze; Jonathan C. Irish; Padraig Warde; Ken Schneider; Robert G. Mackenzie; D. Ian Hodson; J. Alex Hammond; Sunil P.P. Gulavita; Libni J. Eapen; P.F. Dixon; Randy J. Bissett
Clinical Oncology | 2006
Patti A. Groome; Karleen Schulze; S. Keller; William J. Mackillop; Brian O'Sullivan; J. Irish; Randy J. Bissett; P.F. Dixon; Libni J. Eapen; Sunil P.P. Gulavita; J.A. Hammond; D.I. Hodson; Robert G. Mackenzie; Ken Schneider; Padraig Warde