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Dive into the research topics where Douglas A. Stewart is active.

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Featured researches published by Douglas A. Stewart.


The New England Journal of Medicine | 2012

ABVD Alone versus Radiation-Based Therapy in Limited-Stage Hodgkin's Lymphoma

Ralph M. Meyer; Mary Gospodarowicz; Joseph M. Connors; R. Pearcey; Woodrow Wells; Jane N. Winter; Sandra J. Horning; A. Rashid Dar; Chaim Shustik; Douglas A. Stewart; Michael Crump; Marina Djurfeldt; Bingshu E. Chen; Lois E. Shepherd

BACKGROUND Chemotherapy plus radiation treatment is effective in controlling stage IA or IIA nonbulky Hodgkins lymphoma in 90% of patients but is associated with late treatment-related deaths. Chemotherapy alone may improve survival because it is associated with fewer late deaths. METHODS We randomly assigned 405 patients with previously untreated stage IA or IIA nonbulky Hodgkins lymphoma to treatment with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) alone or to treatment with subtotal nodal radiation therapy, with or without ABVD therapy. Patients in the ABVD-only group, both those with a favorable risk profile and those with an unfavorable risk profile, received four to six cycles of ABVD. Among those assigned to subtotal nodal radiation therapy, patients who had a favorable risk profile received subtotal nodal radiation therapy alone and patients with an unfavorable risk profile received two cycles of ABVD plus subtotal nodal radiation therapy. The primary end point was 12-year overall survival. RESULTS The median length of follow-up was 11.3 years. At 12 years, the rate of overall survival was 94% among those receiving ABVD alone, as compared with 87% among those receiving subtotal nodal radiation therapy (hazard ratio for death with ABVD alone, 0.50; 95% confidence interval [CI], 0.25 to 0.99; P=0.04); the rates of freedom from disease progression were 87% and 92% in the two groups, respectively (hazard ratio for disease progression, 1.91; 95% CI, 0.99 to 3.69; P=0.05); and the rates of event-free survival were 85% and 80%, respectively (hazard ratio for event, 0.88; 95% CI, 0.54 to 1.43; P=0.60). Among the patients randomly assigned to ABVD alone, 6 patients died from Hodgkins lymphoma or an early treatment complication and 6 died from another cause; among those receiving radiation therapy, 4 deaths were related to Hodgkins lymphoma or early toxic effects from the treatment and 20 were related to another cause. CONCLUSIONS Among patients with Hodgkins lymphoma, ABVD therapy alone, as compared with treatment that included subtotal nodal radiation therapy, was associated with a higher rate of overall survival owing to a lower rate of death from other causes. (Funded by the Canadian Cancer Society and the National Cancer Institute; HD.6 ClinicalTrials.gov number, NCT00002561.).


Journal of Clinical Oncology | 2003

Intensive Methotrexate and Cytarabine Followed by High-Dose Chemotherapy With Autologous Stem-Cell Rescue in Patients With Newly Diagnosed Primary CNS Lymphoma: An Intent-to-Treat Analysis

Lauren E. Abrey; Craig H. Moskowitz; Warren P. Mason; Michael Crump; Douglas A. Stewart; Peter Forsyth; Nina Paleologos; Denise D. Correa; Nicole D. Anderson; Dawn Caron; Andrew D. Zelenetz; Stephen D. Nimer; Lisa M. DeAngelis

PURPOSE To assess the safety and efficacy of intensive methotrexate-based chemotherapy followed by high-dose chemotherapy (HDT) with autologous stem-cell rescue in patients with newly diagnosed primary CNS lymphoma (PCNSL). PATIENTS AND METHODS Twenty-eight patients received induction chemotherapy using high-dose systemic methotrexate (3.5 g/m2) and cytarabine (3 g/m2 daily for 2 days). Fourteen patients with chemosensitive disease evident on neuroimaging then received high-dose therapy using carmustine, etoposide, cytarabine, and melphalan with autologous stem-cell rescue. RESULTS The objective response rate to the induction-phase chemotherapy was 57%, and median overall survival is not yet assessable, with a median follow-up time of 28 months. The overall median event-free survival time is 5.6 months for all patients and 9.3 months for 14 patients who underwent transplantation. Six of these 14 patients (43%) remained disease-free at last follow-up. Treatment was well tolerated; there was one transplantation-related death. Prospective neuropsychologic evaluations have revealed no evidence of treatment-related neurotoxicity. CONCLUSION This treatment approach is feasible in patients with newly diagnosed PCNSL without evidence of significant related neurotoxicity. Although the transplantation results are similar to those achieved in patients with aggressive or poor-prognosis systemic lymphoma, the low response rate to induction chemotherapy and the significant number of patients who experienced relapse soon after HDT suggest that more aggressive induction chemotherapy may be warranted.


Blood | 2009

Influence of cytogenetics in patients with relapsed or refractory multiple myeloma treated with lenalidomide plus dexamethasone: adverse effect of deletion 17p13

Donna E. Reece; Kevin W. Song; Tommy Fu; Birgitte Roland; Hong Chang; Douglas E. Horsman; Adnan Mansoor; Christine Chen; Esther Masih-Khan; Young Trieu; Helene Bruyere; Douglas A. Stewart; Nizar J. Bahlis

Although the combination of lenalidomide and dexamethasone is effective therapy for patients with relapsed/refractory multiple myeloma, the influence of high-risk cytogenetic abnormalities on outcomes is unknown. This subanalysis of a large, open-label study investigated the effects of the most common unfavorable cytogenetic abnormalities detected by fluorescence in situ hybridization, del(13q), t(4;14), and del(17p13), in 130 evaluable patients treated with this regimen. Whereas patients with either del(13q) or t(4;14) experienced a median time to progression and overall survival comparable with those without these cytogenetic abnormalities, patients with del(17p13) had a significantly worse outcome, with a median time to progression of 2.22 months (hazard ratio, 2.82; P < .001) and median overall survival of 4.67 months (hazard ratio, 3.23; P < .001). Improved therapeutic strategies are required for this subgroup of patients. This study was registered at www.ClinicalTrials.gov as #NCT00179647.


The New England Journal of Medicine | 2013

Autologous Transplantation as Consolidation for Aggressive Non-Hodgkin's Lymphoma

Patrick J. Stiff; Joseph M. Unger; James R. Cook; Louis S. Constine; Stephen Couban; Douglas A. Stewart; Thomas C. Shea; Pierluigi Porcu; Jane N. Winter; Brad S. Kahl; Thomas P. Miller; Raymond R. Tubbs; Deborah Marcellus; Jonathan W. Friedberg; Kevin Barton; Glenn Mills; Michael LeBlanc; Lisa M. Rimsza; Stephen J. Forman; Richard I. Fisher

BACKGROUND The efficacy of autologous stem-cell transplantation during the first remission in patients with diffuse, aggressive non-Hodgkins lymphoma classified as high-intermediate risk or high risk on the International Prognostic Index remains controversial and is untested in the rituximab era. METHODS We treated 397 patients who had disease with an age-adjusted classification of high risk or high-intermediate risk with five cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or CHOP plus rituximab. Patients with a response were randomly assigned to receive three additional cycles of induction chemotherapy (control group) or one additional cycle of induction chemotherapy followed by autologous stem-cell transplantation (transplantation group). The primary efficacy end points were 2-year progression-free survival and overall survival. RESULTS Of 370 induction-eligible patients, 253 were randomly assigned to the transplantation group (125) or the control group (128). Forty-six patients in the transplantation group and 68 in the control group had disease progression or died, with 2-year progression-free survival rates of 69 and 55%, respectively (hazard ratio in the control group vs. the transplantation group, 1.72; 95% confidence interval [CI], 1.18 to 2.51; P=0.005). Thirty-seven patients in the transplantation group and 47 in the control group died, with 2-year overall survival rates of 74 and 71%, respectively (hazard ratio, 1.26; 95% CI, 0.82 to 1.94; P=0.30). Exploratory analyses showed a differential treatment effect according to risk level for both progression-free survival (P=0.04 for interaction) and overall survival (P=0.01 for interaction). Among high-risk patients, the 2-year overall survival rate was 82% in the transplantation group and 64% in the control group. CONCLUSIONS Early autologous stem-cell transplantation improved progression-free survival among patients with high-intermediate-risk or high-risk disease who had a response to induction therapy. Overall survival after transplantation was not improved, probably because of the effectiveness of salvage transplantation. (Funded by the National Cancer Institute, Department of Health and Human Services, and others; SWOG-9704 ClinicalTrials.gov number, NCT00004031.).


Blood | 2012

A phase 1 study of obinutuzumab induction followed by 2 years of maintenance in patients with relapsed CD20-positive B-cell malignancies

Laurie H. Sehn; Sarit Assouline; Douglas A. Stewart; Joy Mangel; Randy D. Gascoyne; Gregg Fine; Susan Frances-Lasserre; David Carlile; Michael Crump

This phase 1 study evaluated the safety, tolerability, pharmacokinetics, and antitumor activity of obinutuzumab (GA101), a glycoengineered type II anti-CD20 monoclonal antibody administered as induction followed by 2 years of maintenance. Cohorts of 3 to 6 patients received obinutuzumab (200-2000 mg) intravenously weekly for 4 weeks. Patients with a complete or partial response (or stable disease and clinical benefit) continued to receive obinutuzumab every 3 months, for a maximum of 8 doses. Twenty-two patients with relapsed CD20-positive non-Hodgkin lymphoma or chronic lymphocytic leukemia with an indication for treatment and no therapy of higher priority were enrolled. Patients received a median of 4 prior regimens; 86% had received at least 1 rituximab-containing regimen. No dose-limiting or unexpected AEs were observed. Infusion-related reactions were most common (all grades, 73%; grade 3/4, 18%), followed by infection (32%), pyrexia (23%), neutropenia (23%), headache (18%), and nausea (18%). At end of induction, 5 (23%) patients achieved partial responses and 12 (54%) had stable disease. Eight patients received maintenance; best overall response was 32% (6 partial responses/1 complete response). Obinutuzumab induction and maintenance therapy was well tolerated with promising efficacy in this heterogeneous, highly pretreated population and warrants further investigation. This study was registered at www.clinicaltrials.gov (identifier NCT00576758).


Biology of Blood and Marrow Transplantation | 2008

High Busulfan Exposure Is Associated with Worse Outcomes in a Daily i.v. Busulfan and Fludarabine Allogeneic Transplant Regimen

Michelle Geddes; S. Bill Kangarloo; Farrukh Naveed; Diana Quinlan; M. Ahsan Chaudhry; Douglas A. Stewart; M. Lynn Savoie; Nizar J. Bahlis; Christopher B. Brown; Jan Storek; Borje S. Andersson; James A. Russell

Low plasma busulfan (Bu) area under the concentration-time curve (AUC) is associated with graft failure and relapsed leukemias, and high AUC with toxicities when Bu is used orally or i.v. 4 times daily combined with cyclophosphamide in myeloablative hematopoietic stem cell transplantation (SCT) conditioning regimens. We report Bu AUC and its association with clinical outcomes in 130 patients with hematologic malignancies given a once-daily i.v. Bu (3.2 mg/kg days -5 to -2) and fludarabine (Flu, 50 mg/m(2) days -6 to -2) regimen. Total-body irradiation (TBI) 200 cGy x 2 was added for 51 patients with acute leukemias. Plasma AUC varied 3.6-fold (2184-7794 microM.min, median 4699 microM.min). Patients with an AUC >6000 microM.min had lower overall survival (OS) than those with AUC < or =6000 microM.min at 12 months (38% versus 74%) and 36 months (23% versus 68%, P < .001). This effect was apparent in patients with standard-risk and high-risk disease, and persisted when potential confounders were considered (hazard ratio 3.2, 95% confidence interval 1.7-6.3). Nonrelapse mortality (NRM) at 100 days (6% versus 19%) and progression free survival (PFS; 58% versus 16%) at 3 years were better with AUC < or =6000 microM.min. These data support a role for therapeutic dose monitoring and dose adjustment with daily i.v. busulfan.


Supportive Care in Cancer | 2004

Association between exercise and quality of life in multiple myeloma cancer survivors

Lee W. Jones; Kerry S. Courneya; Jeffrey K. Vallance; Aliya B. Ladha; Michael J. Mant; Andrew R. Belch; Douglas A. Stewart; Tony Reiman

Goals of the workThe goal of this study was to examine the association between exercise and quality of life (QOL) in multiple myeloma cancer survivors.Patients and methodsUsing a retrospective design, 156 multiple myeloma cancer survivors were mailed a questionnaire that assessed self-reported exercise behavior over three periods (prediagnosis, active treatment, and off-treatment) and QOL.Main resultsThe response rate was 56% (88/156). Descriptive analyses indicated that 6.8% and 20.4% of survivors met national exercise guidelines during active and off-treatment periods, respectively. Exercise during active treatment and off-treatment were positively associated with overall QOL and all subdomains of QOL (all P<0.05) except physical wellbeing.ConclusionsA low percentage of multiple myeloma cancer survivors are exercising regularly either during active or off-treatment periods. Survivors who report more exercise during these periods also report higher QOL. These findings suggest that a randomized controlled trial is warranted.


Biology of Blood and Marrow Transplantation | 2008

Outcomes following HSCT Using Fludarabine, Busulfan, and Thymoglobulin: A Matched Comparison to Allogeneic Transplants Conditioned with Busulfan and Cyclophosphamide

Christopher Bredeson; Mei-Jie Zhang; Manza-A. Agovi; Andrea Bacigalupo; Nizar J. Bahlis; Karen K. Ballen; Chris W. Brown; M. Ahsan Chaudhry; Mary M. Horowitz; Seira Kurian; Diana Quinlan; Catherine E. Muehlenbien; James A. Russell; Lynn Savoie; J. Douglas Rizzo; Douglas A. Stewart

We have reported a lower incidence of acute graft-versus-host disease (aGVHD) with a novel conditioning regimen using low-dose rabbit antithymocyte globulin (ATG; Thymoglobulin [TG]) with fludarabine and intravenous busulfan (FluBuTG). To assess further this single-center experience, we performed a retrospective matched-pair analysis comparing outcomes of adult patients transplanted using the FluBuTG conditioning regimen with matched controls from patients reported to the CIBMTR receiving a first allogeneic hematopoietic stem cell transplant (HCT) after standard oral busulfan and cyclophosphamide (BuCy). One hundred twenty cases and 215 matched controls were available for comparison. Patients receiving FluBuTG had significantly less treatment related mortality (TRM; 12% versus 34%, P < .001) and grades II-IV aGVHD (15% versus 34%, P < .001) compared to BuCy patients. The risk of relapse was higher in the FluBuTG patients (42% versus 20%, P < .001). The risks of chronic GVHD (cGVHD) and disease free survival (DFS) were similar in the cases and controls. These results suggest that the novel regimen FluBuTG decreases the risk of aGVHD and TRM after HLA-identical sibling HSCT, but is associated with an increased risk of relapse, resulting in similar DFS. Whether these conditioning regimens may be more suitable for specific patient populations based on relapse risk requires testing in prospective randomized trials.


Biology of Blood and Marrow Transplantation | 2009

Pharmacokinetics and Pharmacodynamics of Plerixafor in Patients with Non-Hodgkin Lymphoma and Multiple Myeloma

Douglas A. Stewart; Clayton A. Smith; Ron MacFarland; Gary Calandra

Phase I pharmacokinetic (PK) and pharmacodynamic (PD) studies in healthy volunteers demonstrated that plerixafor (AMD3100), a CXCR4 antagonist, administered either alone or with granulocyte colony-stimulating factor (G-CSF), resulted in dose-dependent mobilization of CD34(+) cells in the peripheral blood. The purpose of this study was to evaluate the safety and the PK and PD of plerixafor with G-CSF in patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM). This was a phase II, open-label, single-arm study conducted in 2 centers in Canada. Patients aged 18 to 70 years with NHL or MM eligible for autologous transplantation were eligible. A total of 22 patients (8 with NHL and 14 with MM) were enrolled in the study. The patients were given G-CSF (10 microg/kg/day subcutaneously [s.c.]) for 4 days in the morning and plerixafor 240 microg/kg s.c. on the evening before each day of apheresis. Apheresis was initiated 10 to 11 hours after each evening dose of plerixafor and after the morning dose of G-CSF. This regimen was repeated for up to 5 days or until > or = 5 x 10(6) CD34(+) cells/kg were collected. The objectives were to determine the safety and efficacy of plerixafor in patients with NHL and MM, and the PK and PD of a single 240-microg/kg dose of plerixafor administered after 4 days of G-CSF mobilization in these patients. The median absolute peripheral blood CD34(+) cell count increased from 24.0 cells/microL before plerixafor administration to 75.0 cells/microL before the first apheresis (10 to 11 hours after treatment with plerixafor). The median number of CD34(+) cells collected in a median of 1 day was 5.7 x 10(6) cells/kg in the patients with NHL and 12.0 x 10(6) cells/kg in those with MM. All patients underwent transplantation with prompt and durable engraftment. The PK profile of plerixafor was characterized in 13 patients (5 with NHL and 8 with MM). Overall, the PK parameters were comparable in the patients with NHL and those with MM. Plerixafor was rapidly absorbed after s.c. administration with no observable lag time, with peak plasma concentrations occurring 0.5 hour after administration in most patients. Plerixafor was rapidly cleared, with a median terminal half-life of 4.6 hours. The median maximum increase in the number of circulating cells from baseline was 4.2-fold (range, 3.0- to 5.5-fold), with the maximum fold increase occurring approximately 10 hours after plerixafor injection for all patients. The plerixafor PK and PD profiles in the study patients were consistent with those in healthy volunteers and support the current dosing regimen and timing of apheresis. Plerixafor was safe and effective in mobilizing CD34(+) cells for transplantation.


Journal of Clinical Oncology | 2013

Autologous and Allogeneic Stem-Cell Transplantation for Transformed Follicular Lymphoma: A Report of the Canadian Blood and Marrow Transplant Group

Diego Villa; Michael Crump; Tony Panzarella; Kerry J. Savage; Cynthia L. Toze; Douglas A. Stewart; David MacDonald; Rena Buckstein; Christina R. Lee; Mohsen Alzahrani; Morel Rubinger; Ronan Foley; Anargyros Xenocostas; Mitchell Sabloff; Alexandra Muccilli; Neil Chua; Felix Couture; Jean-François Larouche; Sandra Cohen; Joseph M. Connors; Kimberley Ambler; Abdulwahab J. Al-Tourah; Khaled M. Ramadan; John Kuruvilla

PURPOSE To determine whether autologous (auto) or allogeneic (allo) stem-cell transplantation (SCT) improves outcome in patients with transformed follicular lymphoma compared with rituximab-containing chemotherapy alone. PATIENTS AND METHODS This was a multicenter cohort study of patients with follicular lymphoma and subsequent biopsy-proven aggressive histology transformation. Patient, treatment, and outcome data were collected from each transplantation center and combined for analysis. A separate control group was composed of patients with transformation treated with rituximab-containing chemotherapy but not SCT. The primary end point was overall survival (OS) after transformation. RESULTS One hundred seventy-two patients were identified: 22 (13%) treated with alloSCT, 97 (56%) with autoSCT, and 53 (31%) with rituximab-containing chemotherapy. Five-year OS after transformation was 46% for patients treated with alloSCT, 65% with autoSCT, and 61% with rituximab-containing chemotherapy (P = .24). Five-year progression-free survival (PFS) after transformation was 46% for those treated with alloSCT, 55% with autoSCT, and 40% with rituximab-containing chemotherapy (P = .12). In multivariate analysis, patients treated with autoSCT had improved OS compared with those who received rituximab-containing chemotherapy (hazard ratio [HR], 0.13; 95% CI, 0.05 to 0.34; P < .001). On the other hand, there was no OS difference between those treated with alloSCT and rituximab-containing chemotherapy (HR, 0.44; 95% CI, 0.16 to 1.24; P = .12). OS and PFS after SCT were similar between those treated with autoSCT and alloSCT. Five-year transplantation-related mortality was 23% for those treated with alloSCT and 5% for autoSCT. CONCLUSION Patients undergoing autoSCT had better outcomes than those treated with rituximab-containing chemotherapy alone. AlloSCT did not improve outcome compared with rituximab-containing chemotherapy and was associated with clinically significant toxicity.

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James A. Russell

University of British Columbia

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Peter Duggan

Memorial University of Newfoundland

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