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Selected Works

Edward Yu

Humans

Articles 1 - 10 of 10

Full-Text Articles in Medical Sciences

The Use Of Ct Density Changes At Internal Tissue Interfaces To Correlate Internal Organ Motion With An External Surrogate, Stewart Gaede, Gregory Carnes, Edward Yu, Jake Van Dyk, Jerry Battista, Ting-Yim Lee Jan 2009

The Use Of Ct Density Changes At Internal Tissue Interfaces To Correlate Internal Organ Motion With An External Surrogate, Stewart Gaede, Gregory Carnes, Edward Yu, Jake Van Dyk, Jerry Battista, Ting-Yim Lee

Edward Yu

The purpose of this paper is to describe a non-invasive method to monitor the motion of internal organs affected by respiration without using external markers or spirometry, to test the correlation with external markers, and to calculate any time shift between the datasets. Ten lung cancer patients were CT scanned with a GE LightSpeed Plus 4-Slice CT scanner operating in a ciné mode. We retrospectively reconstructed the raw CT data to obtain consecutive 0.5 s reconstructions at 0.1 s intervals to increase image sampling. We defined regions of interest containing tissue interfaces, including tumour/lung interfaces that move due to breathing …


The Effect Of Timing Of Radiotherapy After Breast-Conserving Surgery In Patients With Positive Or Close Resection Margins, Young Age, And Node-Negative Disease, With Long Term Follow-Up, Olga Vujovic, Anil Cherian, Edward Yu, A. Dar, Larry Stitt, Francisco Perera Oct 2006

The Effect Of Timing Of Radiotherapy After Breast-Conserving Surgery In Patients With Positive Or Close Resection Margins, Young Age, And Node-Negative Disease, With Long Term Follow-Up, Olga Vujovic, Anil Cherian, Edward Yu, A. Dar, Larry Stitt, Francisco Perera

Edward Yu

Purpose: The aim of this study was to determine the effect of timing of radiotherapy after conservative breast surgery on local recurrence in women with positive resection margins and young age, treated without systemic therapy. Methods and materials: A total of 568 patients with T1 and T2, N0 breast cancer were treated with breast-conserving surgery and breast irradiation, between January 1, 1985, and December 31, 1992, at the London Regional Cancer Centre. 63 patients (11.1%) had positive/close resection margins (< 2 mm) and 48 patients (8.4%) were age < or = 40 years. For patients with positive resection margins, the time intervals from breast surgery to breast irradiation used for analysis were, 0 to 8 weeks, > 8 to 12 weeks and > 12 weeks. For patients < or = 40 years, the intervals used for analysis were 0 to 8 weeks and > 8 weeks. Results: Median follow up was 11.2 years. For patients …


Comparative Planning Evaluation Of Intensity-Modulated Radiotherapy Techniques For Complex Lung Cancer Cases, Slav Yartsev, Jeff Chen, Edward Yu, Tomas Kron, George Rodrigues, Terry Coad, Kristina Trenka, Eugene Wong, Glenn Bauman, Jake Van Dyk Jan 2006

Comparative Planning Evaluation Of Intensity-Modulated Radiotherapy Techniques For Complex Lung Cancer Cases, Slav Yartsev, Jeff Chen, Edward Yu, Tomas Kron, George Rodrigues, Terry Coad, Kristina Trenka, Eugene Wong, Glenn Bauman, Jake Van Dyk

Edward Yu

Background and purpose: Lung cancer treatment can be one of the most challenging fields in radiotherapy. The aim of the present study was to compare different modalities of radiation delivery based on a balanced scoring scheme for target coverage and normal tissue avoidance. Patients and methods: Treatment plans were developed for 15 patients with stage III inoperable non-small cell lung cancer using 3D conformal technique and intensity-modulated radiotherapy (IMRT). Elective nodal irradiation was included for all cases to create the most challenging scenarios with large target volumes. A 2 cm margin was used around the gross tumour volume (GTV) to …


Does Sex Influence The Impact That Smoking, Treatment Interruption And Impaired Pulmonary Function Have On Outcomes In Limited Stage Small Cell Lung Cancer Treatment?, Gregory Videtic, Pauline Truong, Robert Ash, Edward Yu, Walter Kocha, Mark Vincent, Anna Tomiak, A Dar, Frances Whiston, Larry Stitt Jun 2005

Does Sex Influence The Impact That Smoking, Treatment Interruption And Impaired Pulmonary Function Have On Outcomes In Limited Stage Small Cell Lung Cancer Treatment?, Gregory Videtic, Pauline Truong, Robert Ash, Edward Yu, Walter Kocha, Mark Vincent, Anna Tomiak, A Dar, Frances Whiston, Larry Stitt

Edward Yu

PURPOSE: To look for survival differences between men and women with limited stage small cell lung cancer (LS-SCLC) by examining stratified variables that impair treatment efficacy. METHODS: A retrospective review of 215 LS-SCLC patients treated from 1989 to 1999 with concurrent chemotherapy-radiotherapy modelled on the 'early-start' thoracic radiotherapy arm of a National Cancer Institute of Canada randomized trial. RESULTS: Of 215 LS-SCLC patients, 126 (58.6%) were men and 89 (41.4%) were women. Smoking status during treatment for 186 patients (86.5%) was: 107 (58%) nonsmoking (NS) (76 [71%] male [M]; 31 [29%] female [F]) and 79 (42%) smoking (S) (36 M …


Planning Evaluation Of Radiotherapy For Complex Lung Cancer Cases Using Helical Tomotherapy, Tomas Kron, Grigor Grigorov, Edward Yu, Slav Yartsev, Jeff Chen, Eugene Wong, George Rodrigues, Kris Trenka, Terry Coad, Glenn Bauman, Jake Van Dyk Aug 2004

Planning Evaluation Of Radiotherapy For Complex Lung Cancer Cases Using Helical Tomotherapy, Tomas Kron, Grigor Grigorov, Edward Yu, Slav Yartsev, Jeff Chen, Eugene Wong, George Rodrigues, Kris Trenka, Terry Coad, Glenn Bauman, Jake Van Dyk

Edward Yu

Lung cancer treatment is one of the most challenging fields in radiotherapy. The aim of the present study was to investigate what role helical tomotherapy (HT), a novel approach to the delivery of highly conformal dose distributions using intensity-modulated radiation fan beams, can play in difficult cases with large target volumes typical for many of these patients. Tomotherapy plans were developed for 15 patients with stage III inoperable non-small-cell lung cancer. While not necessarily clinically indicated, elective nodal irradiation was included for all cases to create the most challenging scenarios with large target volumes. A 2 cm margin was used …


Radiation Treatment Of Lung Cancer--Patterns Of Practice In Canada, Patricia Tai, Edward Yu, Jerry Battista, Jake Van Dyk Apr 2004

Radiation Treatment Of Lung Cancer--Patterns Of Practice In Canada, Patricia Tai, Edward Yu, Jerry Battista, Jake Van Dyk

Edward Yu

BACKGROUND AND PURPOSE: To assess the patterns of practice among Canadian radiation oncologists who treat lung cancers. PATIENTS AND METHODS: A questionnaire detailing different aspects of radiation treatment of lung cancer was mailed to all radiation oncologists treating lung cancer in Canada. Seventy-two percent (74/103) of radiation oncologists who treat lung cancer from all 34 Canadian cancer centres replied to the questionnaire. RESULTS: (a) Radiotherapy regimens in Canadian cancer centres are in accordance with several major randomised studies. There is still some variation in treatment practice that may be due to unresolved controversies or limited resources. The most frequently used …


Improving The Consistency In Cervical Esophageal Target Volume Definition By Special Training, Patricia Tai, Jake Van Dyk, Jerry Battista, Edward Yu, Larry Stitt, Jon Tonita, Olusegun Agboola, James Brierley, Rashid Dar, Christopher Leighton, Shawn Malone, Barbara Strang, Pauline Truong, Gregory Videtic, C. Wong, Rebecca Wong, Youssef Youssef Jun 2002

Improving The Consistency In Cervical Esophageal Target Volume Definition By Special Training, Patricia Tai, Jake Van Dyk, Jerry Battista, Edward Yu, Larry Stitt, Jon Tonita, Olusegun Agboola, James Brierley, Rashid Dar, Christopher Leighton, Shawn Malone, Barbara Strang, Pauline Truong, Gregory Videtic, C. Wong, Rebecca Wong, Youssef Youssef

Edward Yu

PURPOSE: Three-dimensional conformal radiation therapy requires the precise definition of the target volume. Its potential benefits could be offset by the inconsistency in target definition by radiation oncologists. In a previous survey of radiation oncologists, a large degree of variation in target volume definition of cervical esophageal cancer was noted for the boost phase of radiotherapy. The present study evaluated whether special training could improve the consistency in target volume definitions. METHODS AND MATERIALS: A pre-training survey was performed to establish baseline values. This was followed by a special one-on-one training session on treatment planning based on the RTOG 94-05 …


Using Treatment Interruptions To Palliate The Toxicity From Concurrent Chemoradiation For Limited Small Cell Lung Cancer Decreases Survival And Disease Control, Gregory Videtic, Karen Fung, Anna Tomiak, Larry Stitt, A. Dar, Pauline Truong, Edward Yu, Mark Vincent, Walter Kocha Jul 2001

Using Treatment Interruptions To Palliate The Toxicity From Concurrent Chemoradiation For Limited Small Cell Lung Cancer Decreases Survival And Disease Control, Gregory Videtic, Karen Fung, Anna Tomiak, Larry Stitt, A. Dar, Pauline Truong, Edward Yu, Mark Vincent, Walter Kocha

Edward Yu

BACKGROUND AND PURPOSE: We analyzed the impact on survival outcomes of treatment interruptions due to toxicity arising during the concurrent phase of chemotherapy/radiotherapy (ChT/RT) for our limited-stage small-cell cancer (LSCLC) population over the past 10 years. MATERIALS AND METHODS: From 1989 to 1999, 215 patients received treatment for LSCLC, consisting of six cycles of alternating cyclophosphamide/doxorubicin or epirubicin/vincristine (CAV; CEV) and etoposide/cisplatin (EP). Thoracic RT was started with EP at either the second or third cycle (85% of patients). RT dose was either 40 Gy in 15 fractions over 3 weeks or 50 Gy in 25 fractions over 5 weeks, …


Radiation Treatment For Cervical Esophagus: Patterns Of Practice Study In Canada, 1996, Patricia Tai, Jake Van Dyk, Edward Yu, Jerry Battista, Matthew Schmid, Larry Stitt, Jon Tonita, Terry Coad May 2000

Radiation Treatment For Cervical Esophagus: Patterns Of Practice Study In Canada, 1996, Patricia Tai, Jake Van Dyk, Edward Yu, Jerry Battista, Matthew Schmid, Larry Stitt, Jon Tonita, Terry Coad

Edward Yu

PURPOSE: To assess the patterns of practice among Canadian radiation oncologists who treat esophageal cancers, using a trans-Canada survey, completed at the end of 1996. METHODS AND MATERIALS: One of 3 case presentations of different stages of cervical esophageal cancer was randomly assigned and sent to participating radiation oncologists by mail. Respondents were asked to fill in questionnaires regarding treatment techniques and to outline target volumes for the boost phase of radiotherapy. Radiation oncologists from 26 of 27 (96%) of all Canadian centers participated. RESULTS: High-energy X-rays (>/= 10 MV) were employed by 68% of the respondents in part …


Variability Of Target Volume Delineation In Cervical Esophageal Cancer, Patricia Tai, Jake Van Dyk, Edward Yu, Jerry Battista, Larry Stitt, Terry Coad Aug 1998

Variability Of Target Volume Delineation In Cervical Esophageal Cancer, Patricia Tai, Jake Van Dyk, Edward Yu, Jerry Battista, Larry Stitt, Terry Coad

Edward Yu

PURPOSE: Three-dimensional (3D) conformal radiation therapy (CRT) assumes and requires the precise delineation of the target volume. To assess the consistency of target volume delineation by radiation oncologists, who treat esophageal cancers, we have performed a transCanada survey. MATERIALS AND METHODS: One of three case presentations, including CT scan images, of different stages of cervical esophageal cancer was randomly chosen and sent by mail. Respondents were asked to fill in questionnaires regarding treatment techniques and to outline boost target volumes for the primary tumor on CT scans, using ICRU-50 definitions. RESULTS: Of 58 radiation oncologists who agreed to participate, 48 …