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Dive into the research topics where Eng-Siew Koh is active.

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Featured researches published by Eng-Siew Koh.


Cancer | 2007

Individualized estimates of second cancer risks after contemporary radiation therapy for Hodgkin lymphoma

David C. Hodgson; Eng-Siew Koh; Tu Huan Tran; Mostafa Heydarian; R. Tsang; Melania Pintilie; Tony Xu; Lei Huang; Rainer K. Sachs; David J. Brenner

Estimates of radiation‐related second cancer risk among Hodgkin lymphoma survivors are largely based on radiation therapy (RT) fields and doses no longer in use, and these estimates do not account for differences in normal tissue dose among individual patients. This study gives individualized estimates for the risks of lung and female breast cancer expected with contemporary involved‐field RT and low‐dose (20 Gy) RT for mediastinal Hodgkin lymphoma.


Radiation Oncology | 2007

A comparison of mantle versus involved-field radiotherapy for Hodgkin's lymphoma: reduction in normal tissue dose and second cancer risk

Eng-Siew Koh; Tu Huan Tran; Mostafa Heydarian; Rainer K. Sachs; R. Tsang; David J. Brenner; Melania Pintilie; Tony Xu; June Chung; Narinder Paul; David C. Hodgson

BackgroundHodgkins lymphoma (HL) survivors who undergo radiotherapy experience increased risks of second cancers (SC) and cardiac sequelae. To reduce such risks, extended-field radiotherapy (RT) for HL has largely been replaced by involved field radiotherapy (IFRT). While it has generally been assumed that IFRT will reduce SC risks, there are few data that quantify the reduction in dose to normal tissues associated with modern RT practice for patients with mediastinal HL, and no estimates of the expected reduction in SC risk.MethodsOrgan-specific dose-volume histograms (DVH) were generated for 41 patients receiving 35 Gy mantle RT, 35 Gy IFRT, or 20 Gy IFRT, and integrated organ mean doses were compared for the three protocols. Organ-specific SC risk estimates were estimated using a dosimetric risk-modeling approach, analyzing DVH data with quantitative, mechanistic models of radiation-induced cancer.ResultsDose reductions resulted in corresponding reductions in predicted excess relative risks (ERR) for SC induction. Moving from 35 Gy mantle RT to 35 Gy IFRT reduces predicted ERR for female breast and lung cancer by approximately 65%, and for male lung cancer by approximately 35%; moving from 35 Gy IFRT to 20 Gy IFRT reduces predicted ERRs approximately 40% more. The median reduction in integral dose to the whole heart with the transition to 35 Gy IFRT was 35%, with a smaller (2%) reduction in dose to proximal coronary arteries. There was no significant reduction in thyroid dose.ConclusionThe significant decreases estimated for radiation-induced SC risks associated with modern IFRT provide strong support for the use of IFRT to reduce the late effects of treatment. The approach employed here can provide new insight into the risks associated with contemporary IFRT for HL, and may facilitate the counseling of patients regarding the risks associated with this treatment.


Cancer | 2007

Fractionated stereotactic radiotherapy for acoustic neuroma: single-institution experience at The Princess Margaret Hospital.

Eng-Siew Koh; Barbara-Ann Millar; Cynthia Ménard; Howard Michaels; Mostafa Heydarian; Shenaz Ladak; Sharon McKinnon; John A. Rutka; Abhijit Guha; Gregory R. Pond; Normand Laperriere

The clinical outcome and toxicity of fractionated stereotactic radiotherapy (FSRT) was assessed for acoustic neuroma in 60 patients treated in a single institution.


Radiotherapy and Oncology | 2011

Diagnostic and staging impact of radiotherapy planning FDG-PET-CT in non-small-cell lung cancer

Peter Lin; Eng-Siew Koh; Michael Lin; Shalini K Vinod; Ivan Ho-Shon; June Yap; Seu Som

BACKGROUND AND PURPOSE To evaluate whether FDG-PET performed for radiotherapy (RT) planning can detect disease progression, compared with staging PET. MATERIALS AND METHODS Twenty-six patients with newly-diagnosed non-small-cell lung cancer underwent planning PET-CT for curative RT within 8 weeks (mean: 33±14days) of staging PET-CT. Progressive disease (PD) was defined as >25% increase in tumour size (transaxial) or volume, as delineated by SUV threshold of 2.5, or new sites (SUV>2.5). RESULTS The planning PET detected PD in 16 patients (61%), compared to four patients (15%) by CT component of PET-CT. The mean scan interval was longer in patients with progression: 40±12days, compared to 22±11days without progression. Planning PET detected PD in 13/17 (76%), 12/14 (86%) and 7/7 patients if the interval was ≥4, 5 and 6 weeks, respectively, compared with 3/9 patients if interval <4 weeks. Planning PET detected PD in primary metabolic volume in seven patients, 20 new nodal sites in 12 new nodal stations and nine patients, five extra-nodal sites in five patients. This resulted in upstaging in nine patients (35%): stage IIIA in three, IIIB in three and IV in three. CONCLUSIONS RT-planning FDG-PET can provide incremental diagnostic information and may impact on staging in a significant number of patients.


Journal of Medical Imaging and Radiation Oncology | 2009

Impact of a real-time peer review audit on patient management in a radiation oncology department.

Miriam M Boxer; Dion Forstner; Andrew Kneebone; G. Delaney; Eng-Siew Koh; M Fuller; Nasreen Kaadan

In September 2006, the Royal Australian and New Zealand College of Radiologists (RANZCR) endorsed the modified Peer Review Audit Tool (PRAT). We aimed to assess the feasibility of using this tool in a busy radiation oncology department using an electronic medical record (EMR) system, identify areas of compliance and assess the impact of the audit process on patient management. Fortnightly random clinical audit was undertaken by using the revised RANZCR PRAT in the departments of radiation oncology at Liverpool and Macarthur Cancer Therapy Centres (LCTC and MCTC). Following audit of the EMR, treatment plans were audited by peer review. Data were collected prospectively from June 2007 to June 2008. Audits were carried out on 208 patients. Behaviour criteria were well documented in the EMR, but scanning of histology and medical imaging reports did not occur in up to a third of cases. With electronic prescriptions, treatment prescription errors were rare. In total, 8 (3.8%) out of 208 patients had a change to management recommended. Variability in interpretation of PRAT ‘protocol/study’ criteria was identified. We found that real‐time audit is feasible and effective in detecting both issues with documentation in the EMR, and a small number of patients in whom a change to management is recommended. Recommendations have been made in order to continue to improve the audit process including documentation of any changes recommended and whether the recommended change occurred.


Journal of Medical Imaging and Radiation Oncology | 2012

Cost analysis of lung cancer management in South Western Sydney

Sharlyn Kang; Eng-Siew Koh; Shalini K Vinod; Bin Jalaludin

Introduction: Lung cancer is the leading cause of cancer mortality in Western nations, and associated health‐care costs are escalating. The aim of this study was to describe the current pattern of resource use and direct medical costs associated in managing lung cancer in South Western Sydney, Australia.


Clinical Oncology | 2013

Poor Outcomes after Whole Brain Radiotherapy in Patients with Brain Metastases: Results from an International Multicentre Cohort Study

Apsara Windsor; Eng-Siew Koh; S. Allen; Gabriel S. Gabriel; A.E.T. Yeo; R. Allison; Y.M. van der Linden; Michael Barton

AIMS To describe the characteristics and outcomes of cancer patients receiving Whole Brain Radiotherapy (WBRT) and delineate poor outcome groups after WBRT. MATERIALS AND METHODS From 1991 to 2007, 3459 patients receiving WBRT for brain metastases at three centres (in Australia and the Netherlands) were retrospectively reviewed. The effect of clinicodemographic factors, including age, gender, primary cancer, time to WBRT from primary cancer diagnosis and WBRT timing relative to other radiotherapy courses on overall survival, survival from WBRT commencement (WBRT-SV) and death within 6 weeks were analysed. RESULTS WBRT was the first radiotherapy course in 2161/3459 (63%) and the last in 2932/3459 (85%). The most common primary cancer sites with brain metastases were lung (n = 1800; 52%), breast (n = 568; 16%), melanoma (n = 350; 10%) and colorectal (n = 209; 6%). The median time to WBRT from primary cancer diagnosis was 34 weeks, overall survival 1.42 years (0.04-28.70) and WBRT-SV 0.33 years (0-8.60). Older age, male gender and a shorter time from the primary cancer diagnosis to WBRT predicted worse overall survival and WBRT-SV. Seventeen per cent survived less than 6 weeks. Older patients with a shorter time from the primary cancer diagnosis to WBRT and a lower WBRT episode number were more likely to die less than 6 weeks after WBRT. CONCLUSIONS Cancer patients with brain metastases have poor overall outcomes. High mortality within 6 weeks of starting WBRT suggests patient selection remains challenging.


Radiation Oncology | 2011

Evaluation of early imaging response criteria in glioblastoma multiforme

Adam Gladwish; Eng-Siew Koh; Jeremy D.P. Hoisak; Gina Lockwood; Barbara-Ann Millar; Warren P. Mason; Eugene Yu; Normand Laperriere; Cynthia Ménard

BackgroundEarly and accurate prediction of response to cancer treatment through imaging criteria is particularly important in rapidly progressive malignancies such as Glioblastoma Multiforme (GBM). We sought to assess the predictive value of structural imaging response criteria one month after concurrent chemotherapy and radiotherapy (RT) in patients with GBM.MethodsThirty patients were enrolled from 2005 to 2007 (median follow-up 22 months). Tumor volumes were delineated at the boundary of abnormal contrast enhancement on T1-weighted images prior to and 1 month after RT. Clinical Progression [CP] occurred when clinical and/or radiological events led to a change in chemotherapy management. Early Radiologic Progression [ERP] was defined as the qualitative interpretation of radiological progression one month post-RT. Patients with ERP were determined pseudoprogressors if clinically stable for ≥6 months. Receiver-operator characteristics were calculated for RECIST and MacDonald criteria, along with alternative thresholds against 1 year CP-free survival and 2 year overall survival (OS).Results13 patients (52%) were found to have ERP, of whom 5 (38.5%) were pseudoprogressors. Patients with ERP had a lower median OS (11.2 mo) than those without (not reached) (p < 0.001). True progressors fared worse than pseudoprogressors (median survival 7.2 mo vs. 19.0 mo, p < 0.001). Volume thresholds performed slightly better compared to area and diameter thresholds in ROC analysis. Responses of > 25% in volume or > 15% in area were most predictive of OS.ConclusionsWe show that while a subjective interpretation of early radiological progression from baseline is generally associated with poor outcome, true progressors cannot be distinguished from pseudoprogressors. In contrast, the magnitude of early imaging volumetric response may be a predictive and quantitative metric of favorable outcome.


Frontiers in Oncology | 2015

Screening for Psychological Distress in Adult Primary Brain Tumor Patients and Caregivers: Considerations for Cancer Care Coordination.

Wafa Trad; Eng-Siew Koh; Maysaa Daher; Alanah Bailey; Marina Kastelan; Dianne Legge; Marcia Fleet; Grahame Simpson; Elizabeth Hovey

Introduction This study aimed to assess psychological distress (PD) as scored by the Distress Thermometer (DT) in adult primary brain tumor patients and caregivers (CGs) in a clinic setting and ascertain if any high-risk subgroups for PD exist. Material and methods From May 2012 to August 2013, n = 96 patients and n = 32 CG underwent DT screening at diagnosis, and a differing cohort of n = 12 patients and n = 14 CGs at first recurrence. Groups were described by diagnosis (high grade, low grade, and benign) and English versus non English speaking. Those with DT score ≥4 met caseness criteria for referral to psycho-oncology services. One-way ANOVA tests were conducted to test for between-group differences where appropriate. Results At diagnosis and first recurrence, 37.5 and 75.0% (respectively) of patients had DT scores above the cutoff for distress. At diagnosis, 78.1% of CGs met caseness criteria for distress. All CGs at recurrence met distress criterion. Patients with high-grade glioma had significantly higher scores than those with a benign tumor. For patients at diagnosis, non English speaking participants did not report significantly higher DT scores than English speaking participants. Discussion Psychological distress is particularly elevated in CGs and in patients with high-grade glioma at diagnosis. Effective PD screening, triage, and referral by skilled care coordinators are vital to enable timely needs assessment, psychological support, and effective intervention.


Brain Injury | 2012

A multi-tiered intervention to address behavioural and cognitive changes after diagnosis of primary brain tumour: A feasibility study

Diane L. Whiting; Grahame Simpson; Eng-Siew Koh; Kylie M. Wright; Teresa Simpson; Rochelle Firth

Purpose: Untreated behavioural and cognitive changes after primary brain tumour (PBT) can result in challenging behaviours (CBs), with limited documentation on treatment approaches. This study explored the feasibility of employing a Behavioural Consultancy approach to manage CBs, targeting individuals with PBT, family and treating staff. Methods: Participants were patients and families of two hospitals and health professionals from cancer/neurological services. A single-case experimental design piloted skill-based training and environmental changes in managing socio-behavioural impairments in a person with a low grade astrocytoma. A half-day workshop to train family members (n = 7) in compensatory strategy use to manage CBs after PBT was piloted. Finally, a 1-day workshop was provided to 43 health professionals in managing CBs after PBT. For both workshops, a pre–post impact evaluation was conducted employing a purpose-designed Strategies Use Measure. Results: All three interventions demonstrated positive results. The single case showed a 71% decrease in the target behaviour (time spent talking) post-intervention. Some attrition to these gains was observed at two follow-up time points (3 and 5 months). Participants from both workshops demonstrated significant post-intervention increases in perceived knowledge of Strategy Use (family members z = 2.03, p < 0.05; health professionals z = 4.95, p < 0.00; Wilcoxon signed-rank test). Conclusions: These initial studies highlight the potential of employing an integrated multi-tiered intervention based on a Behavioural Consultancy model to manage CBs after PBT.

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Vikneswary Batumalai

University of New South Wales

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Geoff Delaney

University of New South Wales

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G. Delaney

University of New South Wales

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Miriam M Boxer

University of New South Wales

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Shalini K Vinod

University of New South Wales

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