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Dive into the research topics where Garth Nicholas is active.

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Featured researches published by Garth Nicholas.


The New England Journal of Medicine | 2013

Probability of Cancer in Pulmonary Nodules Detected on First Screening CT

Annette McWilliams; Martin C. Tammemagi; John R. Mayo; Heidi C. Roberts; Geoffrey Liu; Kam Soghrati; Kazuhiro Yasufuku; Simon Martel; Francis Laberge; Michel Gingras; Sukhinder Atkar-Khattra; Christine D. Berg; Kenneth G. Evans; Richard J. Finley; John Yee; John C. English; Paola Nasute; John R. Goffin; Serge Puksa; Lori Stewart; Scott Tsai; Michael R. Johnston; Daria Manos; Garth Nicholas; Glenwood D. Goss; Jean M. Seely; Kayvan Amjadi; Alain Tremblay; Paul Burrowes; Paul MacEachern

BACKGROUND Major issues in the implementation of screening for lung cancer by means of low-dose computed tomography (CT) are the definition of a positive result and the management of lung nodules detected on the scans. We conducted a population-based prospective study to determine factors predicting the probability that lung nodules detected on the first screening low-dose CT scans are malignant or will be found to be malignant on follow-up. METHODS We analyzed data from two cohorts of participants undergoing low-dose CT screening. The development data set included participants in the Pan-Canadian Early Detection of Lung Cancer Study (PanCan). The validation data set included participants involved in chemoprevention trials at the British Columbia Cancer Agency (BCCA), sponsored by the U.S. National Cancer Institute. The final outcomes of all nodules of any size that were detected on baseline low-dose CT scans were tracked. Parsimonious and fuller multivariable logistic-regression models were prepared to estimate the probability of lung cancer. RESULTS In the PanCan data set, 1871 persons had 7008 nodules, of which 102 were malignant, and in the BCCA data set, 1090 persons had 5021 nodules, of which 42 were malignant. Among persons with nodules, the rates of cancer in the two data sets were 5.5% and 3.7%, respectively. Predictors of cancer in the model included older age, female sex, family history of lung cancer, emphysema, larger nodule size, location of the nodule in the upper lobe, part-solid nodule type, lower nodule count, and spiculation. Our final parsimonious and full models showed excellent discrimination and calibration, with areas under the receiver-operating-characteristic curve of more than 0.90, even for nodules that were 10 mm or smaller in the validation set. CONCLUSIONS Predictive tools based on patient and nodule characteristics can be used to accurately estimate the probability that lung nodules detected on baseline screening low-dose CT scans are malignant. (Funded by the Terry Fox Research Institute and others; ClinicalTrials.gov number, NCT00751660.).


JAMA | 2017

Effect of tumor-treating fields plus maintenance temozolomide vs maintenance temozolomide alone on survival in patients with glioblastoma a randomized clinical trial

Roger Stupp; Sophie Taillibert; Andrew A. Kanner; William L. Read; David M. Steinberg; Benoit Lhermitte; Steven A. Toms; Ahmed Idbaih; Manmeet S. Ahluwalia; Karen Fink; Francesco Di Meco; Frank S. Lieberman; Jay Jiguang Zhu; Giuseppe Stragliotto; David D. Tran; Steven Brem; Andreas F. Hottinger; Eilon D. Kirson; Gitit Lavy-Shahaf; Uri Weinberg; Chae Yong Kim; Sun Ha Paek; Garth Nicholas; Jordi Burna; Hal Hirte; Michael Weller; Yoram Palti; Monika E. Hegi; Zvi Ram

Importance Tumor-treating fields (TTFields) is an antimitotic treatment modality that interferes with glioblastoma cell division and organelle assembly by delivering low-intensity alternating electric fields to the tumor. Objective To investigate whether TTFields improves progression-free and overall survival of patients with glioblastoma, a fatal disease that commonly recurs at the initial tumor site or in the central nervous system. Design, Setting, and Participants In this randomized, open-label trial, 695 patients with glioblastoma whose tumor was resected or biopsied and had completed concomitant radiochemotherapy (median time from diagnosis to randomization, 3.8 months) were enrolled at 83 centers (July 2009-2014) and followed up through December 2016. A preliminary report from this trial was published in 2015; this report describes the final analysis. Interventions Patients were randomized 2:1 to TTFields plus maintenance temozolomide chemotherapy (n = 466) or temozolomide alone (n = 229). The TTFields, consisting of low-intensity, 200 kHz frequency, alternating electric fields, was delivered (≥ 18 hours/d) via 4 transducer arrays on the shaved scalp and connected to a portable device. Temozolomide was administered to both groups (150-200 mg/m2) for 5 days per 28-day cycle (6-12 cycles). Main Outcomes and Measures Progression-free survival (tested at &agr; = .046). The secondary end point was overall survival (tested hierarchically at &agr; = .048). Analyses were performed for the intent-to-treat population. Adverse events were compared by group. Results Of the 695 randomized patients (median age, 56 years; IQR, 48-63; 473 men [68%]), 637 (92%) completed the trial. Median progression-free survival from randomization was 6.7 months in the TTFields-temozolomide group and 4.0 months in the temozolomide-alone group (HR, 0.63; 95% CI, 0.52-0.76; P < .001). Median overall survival was 20.9 months in the TTFields-temozolomide group vs 16.0 months in the temozolomide-alone group (HR, 0.63; 95% CI, 0.53-0.76; P < .001). Systemic adverse event frequency was 48% in the TTFields-temozolomide group and 44% in the temozolomide-alone group. Mild to moderate skin toxicity underneath the transducer arrays occurred in 52% of patients who received TTFields-temozolomide vs no patients who received temozolomide alone. Conclusions and Relevance In the final analysis of this randomized clinical trial of patients with glioblastoma who had received standard radiochemotherapy, the addition of TTFields to maintenance temozolomide chemotherapy vs maintenance temozolomide alone, resulted in statistically significant improvement in progression-free survival and overall survival. These results are consistent with the previous interim analysis. Trial Registration clinicaltrials.gov Identifier: NCT00916409


Journal of Thoracic Oncology | 2012

Phase I/II trial of custirsen (OGX-011), an inhibitor of clusterin, in combination with a gemcitabine and platinum regimen in patients with previously untreated advanced non-small cell lung cancer.

Janessa Laskin; Garth Nicholas; Christopher W. Lee; Barbara J. Gitlitz; Mark Vincent; Yvon Cormier; Joe Stephenson; Yee Ung; Rachel Sanborn; Bryn Pressnail; Francis Nugent; John Nemunaitis; Martin E. Gleave; Nevin Murray; Desiree Hao

Purpose: Clusterin (CLU), an antiapoptotic, stress-associated protein, confers resistance to therapy when overexpressed. This trial tested custirsen (OGX-011), an inhibitor of CLU protein production, combined with gemcitabine/platinum in patients with advanced non-small cell lung cancer (NSCLC). Patients and Methods: This was a single-arm, multicenter, phase I/II study in chemotherapy-naive stage IIIB/IV NSCLC. Custirsen was infused during a loading dose period and weekly in combination with gemcitabine (1250 mg/m2) on days 1 and 8 and with cisplatin (75 mg/m2) or carboplatin (area under the curve 5) on day 1 of each 21-day cycle. Ten patients were treated in a phase I lead-in and 71 in the phase II component. The primary efficacy endpoint was response rate, with exploratory analyses of other efficacy outcomes and biomarker relationships. Results: Eighty-one patients received custirsen and were included in the primary analysis. The median age was 61 years; 82% had stage IV disease. Overall response was 25 of 81 (31%; 95% confidence interval 21–42). The 1- and 2-year survivals were 54 and 30%, respectively. Toxicity of the combination was not appreciably different from what is reported for gemcitabine/platinum combinations. Custirsen treatment decreased serum CLU levels in 95% of patients evaluated. Patients who achieved a minimum median CLU level for the population of ⩽38 &mgr;g/ml during treatment had a median survival of 27.1 compared with 16.1 months for patients who did not (p = 0.02). Conclusion: Based on the above results, a randomized phase 3 trial to evaluate the survival benefit of custirsen in patients with NSCLC is warranted.


American Journal of Clinical Oncology | 2007

A population-based analysis of second primary cancers after irradiation for rectal cancer

Wayne S. Kendal; Garth Nicholas

Objective:To investigate the possible association between pelvic irradiation for rectal cancer and subsequent second primary cancers. Patients and Methods:A population-based analysis of 20,910 individuals with rectal cancer from the Surveillance, Epidemiology, and End Results registry, for whom follow-up times were at least 5 years, was performed. Kaplan-Meier estimates for the development of second cancers within irradiated and nonirradiated cohorts provided a comparison that accounted for censored data. Cox proportional hazards analyses were further conducted to compensate for patient and tumor-related factors. Results:A total of 656 (12%) and 2368 (16%) second primary cancers were enumerated from the irradiated and nonirradiated cohorts, respectively, with the proportion of second primary cancers within the irradiated cohort being significantly decreased (P < 0.001) on crude analysis. However, Kaplan-Meier and Cox analyses revealed no significant difference between the 2 cohorts when all second primary cancer sites were considered together (hazard ratio = 1.02; 95% confidence interval [CI], 0.92–1.12). Proportional hazards analysis for specific second primary sites revealed a decreased risk after pelvic irradiation for cancer of the prostate (hazard ratio = 0.63; 95% CI, 0.48–0.84), and an increased risk for cancers of the uterine corpus & cervix (hazard ratio = 2.5; 95% CI, 1.6–4.0). Conclusion:Second primary cancers after irradiation for rectal cancers appear relatively infrequent compared with the background incidence of spontaneous cancers, and should not factor into treatment decisions for this older population. We hypothesize that the incidence of second primary tumors within adjacent organs could represent a balance between the radiation-induction of tumors and the radiation-inhibition of spontaneously occurring tumors.


PLOS Medicine | 2017

Performance and Cost-Effectiveness of Computed Tomography Lung Cancer Screening Scenarios in a Population-Based Setting: A Microsimulation Modeling Analysis in Ontario, Canada

Kevin ten Haaf; Martin C. Tammemagi; Susan J. Bondy; Carlijn M. van der Aalst; Sumei Gu; S. Elizabeth McGregor; Garth Nicholas; Harry J. de Koning; Lawrence Paszat

Background The National Lung Screening Trial (NLST) results indicate that computed tomography (CT) lung cancer screening for current and former smokers with three annual screens can be cost-effective in a trial setting. However, the cost-effectiveness in a population-based setting with >3 screening rounds is uncertain. Therefore, the objective of this study was to estimate the cost-effectiveness of lung cancer screening in a population-based setting in Ontario, Canada, and evaluate the effects of screening eligibility criteria. Methods and Findings This study used microsimulation modeling informed by various data sources, including the Ontario Health Insurance Plan (OHIP), Ontario Cancer Registry, smoking behavior surveys, and the NLST. Persons, born between 1940 and 1969, were examined from a third-party health care payer perspective across a lifetime horizon. Starting in 2015, 576 CT screening scenarios were examined, varying by age to start and end screening, smoking eligibility criteria, and screening interval. Among the examined outcome measures were lung cancer deaths averted, life-years gained, percentage ever screened, costs (in 2015 Canadian dollars), and overdiagnosis. The results of the base-case analysis indicated that annual screening was more cost-effective than biennial screening. Scenarios with eligibility criteria that required as few as 20 pack-years were dominated by scenarios that required higher numbers of accumulated pack-years. In general, scenarios that applied stringent smoking eligibility criteria (i.e., requiring higher levels of accumulated smoking exposure) were more cost-effective than scenarios with less stringent smoking eligibility criteria, with modest differences in life-years gained. Annual screening between ages 55–75 for persons who smoked ≥40 pack-years and who currently smoke or quit ≤10 y ago yielded an incremental cost-effectiveness ratio of


Journal of Thoracic Oncology | 2014

Resource utilization and costs during the initial years of lung cancer screening with computed tomography in Canada.

Sonya Cressman; Stephen Lam; Martin C. Tammemagi; William K. Evans; Natasha B. Leighl; Dean A. Regier; Corneliu Bolbocean; Frances A. Shepherd; Ming-Sound Tsao; Daria Manos; Geoffrey Liu; Sukhinder Atkar-Khattra; Ian Cromwell; Michael R. Johnston; John R. Mayo; Annette McWilliams; Christian Couture; John C. English; John R. Goffin; David M. Hwang; Serge Puksa; Heidi Roberts; Alain Tremblay; Paul MacEachern; Paul Burrowes; Rick Bhatia; Richard J. Finley; Glenwood D. Goss; Garth Nicholas; Jean M. Seely

41,136 Canadian dollars (


Journal of Thoracic Oncology | 2017

The Cost-Effectiveness of High-Risk Lung Cancer Screening and Drivers of Program Efficiency

Sonya Cressman; Stuart Peacock; Martin C. Tammemagi; William K. Evans; N. Leighl; John R. Goffin; Alain Tremblay; Geoffrey Liu; Daria Manos; Paul MacEachern; Rick Bhatia; Serge Puksa; Garth Nicholas; Annette McWilliams; John R. Mayo; John Yee; John C. English; Reka Pataky; Emily McPherson; Sukhinder Atkar-Khattra; Michael R. Johnston; Heidi Schmidt; Frances A. Shepherd; Kam Soghrati; Kayvan Amjadi; Paul Burrowes; Christian Couture; Harmanjatinder S. Sekhon; Kazuhiro Yasufuku; Glenwood D. Goss

33,825 in May 1, 2015, United States dollars) per life-year gained (compared to annual screening between ages 60–75 for persons who smoked ≥40 pack-years and who currently smoke or quit ≤10 y ago), which was considered optimal at a cost-effectiveness threshold of


European Respiratory Journal | 2015

Plasma pro-surfactant protein B and lung function decline in smokers

Janice M. Leung; John R. Mayo; Wan C. Tan; C. Martin Tammemagi; Geoffrey Liu; Stuart Peacock; Frances A. Shepherd; John R. Goffin; Glenwood D. Goss; Garth Nicholas; Alain Tremblay; Michael R. Johnston; Simon Martel; Francis Laberge; Rick Bhatia; Heidi Roberts; Paul Burrowes; Daria Manos; Lori Stewart; Michel Gingras; Sergio Pasian; Ming-Sound Tsao; Stephen Lam; Don D. Sin

50,000 Canadian dollars (


Cancer Research | 2017

Abstract CT007: Tumor treating fields added to standard chemotherapy in newly diagnosed glioblastoma (GBM): Final results of a randomized, multi-center, phase III trial

Roger Stupp; Monika E. Hegi; Ahmed Idbaih; David M. Steinberg; Benoit Lhermitte; William Read; Steven A. Toms; Gene H. Barnett; Garth Nicholas; Chae-Yong Kim; Karen Fink; Andrea Salmaggi; Frank S. Lieberman; Jay-Jiguang Zhu; Lynne P. Taylor; Giuseppe Stragliotto; Andreas F. Hottinger; Eilon D. Kirson; Uri Weinberg; Yoram Palti; Zvi Ram

41,114 May 1, 2015, US dollars). If 50% lower or higher attributable costs were assumed, the incremental cost-effectiveness ratio of this scenario was estimated to be


Oncotarget | 2017

A phase I study of foretinib plus erlotinib in patients with previously treated advanced non-small cell lung cancer: Canadian cancer trials group IND.196

Natasha B. Leighl; Ming-Sound Tsao; Geoffrey Liu; Dongsheng Tu; Cheryl Ho; Frances A. Shepherd; Nevin Murray; John R. Goffin; Garth Nicholas; Shingo Sakashita; Zhuo Chen; Lucia Kim; Jean Powers; Lesley Seymour; Glenwood D. Goss; Penelope Ann Bradbury

38,240 (

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John R. Goffin

Juravinski Cancer Centre

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Frances A. Shepherd

Princess Margaret Cancer Centre

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Geoffrey Liu

Princess Margaret Cancer Centre

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Michael R. Johnston

Queen Elizabeth II Health Sciences Centre

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Ming-Sound Tsao

Princess Margaret Cancer Centre

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