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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 …


Monte Carlo Simulations Of Dna Damage From Incorporated Cold Iodine Following Photoelectrically Induced Auger Electron Cascades, V. Moiseenko, S. Karnas, E. Yu, J. Battista Dec 2001

Monte Carlo Simulations Of Dna Damage From Incorporated Cold Iodine Following Photoelectrically Induced Auger Electron Cascades, V. Moiseenko, S. Karnas, E. Yu, J. Battista

Edward Yu

Radiation-induced damage in nucleosomal DNA from Auger electron cascades due to incorporated cold IUdR has been modelled through Monte Carlo simulations. Probabilities of DNA double strand break (DSB) production following a vacancy in the K, L, M and N shells of iodine are estimated. DSB complexity from the base damage accompanying a break was also estimated. Multiple DSB events were analysed for correlated breaks due to nucleosome periodicity. The probability of an Auger cascade causing at least one DSB strongly depended on the shell in which the initial vacancy was produced. This probability was approximately 0.35 for K and L …


Prophylactic Cranial Irradiation Revisited: Cost-Effectiveness And Quality Of Life In Small-Cell Lung Cancer, T. Tai, Edward Yu, Peter Dickof, Glen Beck, Jon Tonita, Tete Ago, David Skarsgard, Marlene Schmidt, Matthew Schmid, John Liem Dec 2001

Prophylactic Cranial Irradiation Revisited: Cost-Effectiveness And Quality Of Life In Small-Cell Lung Cancer, T. Tai, Edward Yu, Peter Dickof, Glen Beck, Jon Tonita, Tete Ago, David Skarsgard, Marlene Schmidt, Matthew Schmid, John Liem

Edward Yu

PURPOSE: To investigate the therapeutic usefulness and cost-effectiveness of prophylactic cranial irradiation (PCI) in patients with limited-stage small-cell lung cancer (SCLC) who had achieved a complete remission. METHODS: A retrospective chart review was undertaken of all patients diagnosed in Saskatchewan with SCLC between 1987 and 1998 inclusive. Patients who achieved a complete remission were divided into two groups, depending on whether they underwent PCI (PCI+ and PCI-, respectively). The quality-of-life-adjusted survival was estimated by the Q-TWiST method (quality time without symptoms and toxicity). The mean incremental costs per month of incremental OS were calculated in a cost-effectiveness analysis. RESULTS: Among …


Computed Tomography To Assess Pulmonary Injury Associated With Concurrent Chemo-Radiotherapy For Inoperable Non-Small Cell Lung Cancer, Galit Aviram, Edward Yu, Patricia Tai, Michael Lefcoe Nov 2001

Computed Tomography To Assess Pulmonary Injury Associated With Concurrent Chemo-Radiotherapy For Inoperable Non-Small Cell Lung Cancer, Galit Aviram, Edward Yu, Patricia Tai, Michael Lefcoe

Edward Yu

OBJECTIVE: To characterize serial computed tomography (CT) findings of pulmonary injury after a uniform regimen of concurrent chemo-radiotherapy in inoperable non-small cell lung cancer, and to compare the radiation-induced lung toxicity with other concurrent chemo-radiation regimens. METHODS: Twenty-four patients with advanced non-small cell lung cancer received 2 induction cycles of cisplatin and vinblastine, followed by 2 further cycles of cisplatin and vinblastine, concurrent with 60 Gy radiation at 2 Gy per fraction. Radiation-induced lung injury in the acute and chronic phases was assessed by serial CT scans and compared with preradiation baseline scans. Acute radiation pneumonitis was evaluated using the …


Monte Carlo Simulations And Measurement Of Dna Damage From X-Ray-Triggered Auger Cascades In Iododeoxyuridine (Iudr), S. Karnas, V. Moiseenko, E. Yu, P. Truong, J. Battista Aug 2001

Monte Carlo Simulations And Measurement Of Dna Damage From X-Ray-Triggered Auger Cascades In Iododeoxyuridine (Iudr), S. Karnas, V. Moiseenko, E. Yu, P. Truong, J. Battista

Edward Yu

We investigated the DNA damage from Auger electrons emitted from incorporated stable iodine (127I), following photoelectric absorption of external x-rays. The effectiveness of the Auger electrons in producing DNA double-strand breaks (DSB) was determined theoretically, using Monte Carlo simulations of the radiation physics and chemistry, and was shown to be in reasonable agreement with DNA damage measured using the comet assay. The DSB yields were measured in CHO cells for 60Co (as a non-Auger-promoting radiation) and for tungsten-filtered 100 kVp x-rays capable of producing Auger electron emission. The theoretical study showed that on average, 2.5 Auger electrons were emitted for …


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, …


Practice Guideline On Prophylactic Cranial Irradiation In Small-Cell Lung Cancer, Jaro Kotalik, Edward Yu, Barbara Markman, William Evans May 2001

Practice Guideline On Prophylactic Cranial Irradiation In Small-Cell Lung Cancer, Jaro Kotalik, Edward Yu, Barbara Markman, William Evans

Edward Yu

Purpose: To develop an evidence-based clinical practice guideline that would address the following questions: (a) What is the role of prophylactic cranial irradiation (PCI) in patients with limited or extensive stage small-cell lung cancer (SCLC) who have achieved complete remission in response to induction therapy (chemotherapy or chemoradiotherapy)? (b) What dose and fractionation schedules of PCI are optimal? (c) Does the use of PCI in patients with SCLC in complete remission affect quality of life? Survival, disease-free survival, quality of life, and adverse effects were the outcomes of interest. Methods and materials: A systematic review of the published literature was …


Merkel Cell Carcinoma Of The Skin, Patricia Tai, Edward Yu, Jon Tonita, James Gilchrist Sep 2000

Merkel Cell Carcinoma Of The Skin, Patricia Tai, Edward Yu, Jon Tonita, James Gilchrist

Edward Yu

Background: Neuroendocrine/Merkel cell carcinoma (MCC) of the skin is an uncommon tumour. Currently, there are only limited data available on the natural history, prognostic factors, and patient management of MCC. Objective: To review our experience and build the largest database from the literature. Methods: Twenty-eight cases from the London Regional Cancer Center were combined with 633 cases obtained from the literature searched in English, French, German, and Chinese for the years 1966 to 1998. The database included age, sex, initial disease status at presentation to the clinic, site of primary, any coexisting disease, any previous irradiation, sizes of primary/nodal/distant metas-tases, …


Chemotherapy In Neuroendocrine/Merkel Cell Carcinoma Of The Skin: Case Series And Review Of 204 Cases, Patricia Tai, Edward Yu, Eric Winquist, Alex Hammond, Larry Stitt, Jan Tonita, Jim Gilchrist May 2000

Chemotherapy In Neuroendocrine/Merkel Cell Carcinoma Of The Skin: Case Series And Review Of 204 Cases, Patricia Tai, Edward Yu, Eric Winquist, Alex Hammond, Larry Stitt, Jan Tonita, Jim Gilchrist

Edward Yu

Purpose: To study the use of chemotherapy for Merkel cell carcinoma (MCC) of the skin. Patients and methods: Twenty-five cases of MCC were treated at the London Regional Cancer Center between 1987 and 1997. Thirteen cases treated with chemotherapy were reviewed with 191 cases from the literature. Results: At presentation, 24 patients had localized skin lesions (stage I) and one had locoregional involvement (stage II). Among the nine cases with recurrent nodal disease, six had chemotherapy as a component of salvage treatment. They were all free of disease at a median of 19 months (range, 12 to 37 months). In …


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 …


Functional Infrared Imaging Of The Breast, J. Keyserlingk, P. Ahlgren, E. Yu, N. Belliveau, M. Yassa Apr 2000

Functional Infrared Imaging Of The Breast, J. Keyserlingk, P. Ahlgren, E. Yu, N. Belliveau, M. Yassa

Edward Yu

In order to re-assess the potential contribution of infrared (IR) imaging as a first-line component of a multi-imaging strategy using currently available technology, we first review the history of its introduction and clinical application, including the results of the Breast Cancer Detection Demonstration Projects (BCDDP). We then discuss experiments with a new high-resolution, computerized IR station and software program acquired by the Ville Marie Breast Center to assess IR imaging's ability to complement clinical examination and mammography in the early detection of breast cancer. Our goal is to show that high-resolution IR imaging provides additional safe, practical, and objective information …


Altered Fractionation Of Radical Radiation Therapy In The Management Of Unresectable Non-Small Cell Lung Cancer, E. Yu, K. Lochrin, P. Dixon, Y. Ung, A. Gagliardi, W. K. Evans Dec 1999

Altered Fractionation Of Radical Radiation Therapy In The Management Of Unresectable Non-Small Cell Lung Cancer, E. Yu, K. Lochrin, P. Dixon, Y. Ung, A. Gagliardi, W. K. Evans

Edward Yu

No abstract provided.


Optimal Photon Energies For Iudr K-Edge Radiosensitization With Filtered X-Ray And Radioisotope Sources, S. Karnas, E. Yu, R. Mcgarry, J. Battista Sep 1999

Optimal Photon Energies For Iudr K-Edge Radiosensitization With Filtered X-Ray And Radioisotope Sources, S. Karnas, E. Yu, R. Mcgarry, J. Battista

Edward Yu

The purpose of this work is to determine the most physically effective radiation energy for K-edge absorption of x- or gamma-rays by iododeoxyuridine (IUdR) on Chinese hamster ovary (CHO) cells. Brachytherapy sources (Sm-145, I-125, Yb-169 and Am-241) and x-ray beams (30 kVp, 100 kVp and 100 kVp with gold, gadolinium, lead or tungsten filtration) were investigated for their preferential absorption qualities by IUdR sensitized DNA. The 30 kVp, 100 kVp and 100 kVp with tungsten filtration were then used to irradiate CHO cells, with or without IUdR incorporation (i.e. 10(-5) M of IUdR for 3 days). Radiation absorption calculations were …


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 …


Infrared Imaging Of The Breast: Initial Reappraisal Using High-Resolution Digital Technology In 100 Successive Cases Of Stage I And Ii Breast Cancer, J. Keyserlingk, P. Ahlgren, E. Yu, N. Belliveau Jun 1998

Infrared Imaging Of The Breast: Initial Reappraisal Using High-Resolution Digital Technology In 100 Successive Cases Of Stage I And Ii Breast Cancer, J. Keyserlingk, P. Ahlgren, E. Yu, N. Belliveau

Edward Yu

There is a general consensus that earlier detection of breast cancer should result in improved survival. Current breast imaging relies primarily on mammography. Despite better equipement and regulation, variability in interpretation and tissue density still affect accuracy. A number of adjuvant imaging techniques are currently being used, including doppler ultrasound and gadolinium-enhanced MRI, which can detect cancer-induced neovascularity. In order to assess the potential contribution of currently available high-resolution digital infrared technology capable of recognizing minute regional vascular flow related temperature variation, we retrospecitively reviewed the relative ability of our preoperative clinical exam, mammography, and infrared imaging to detect 100 …


Does Delay In Breast Irradiation Following Conservative Breast Surgery In Node-Negative Breast Cancer Patients Have An Impact On Risk Of Recurrence?, Olga Vujovic, Francisco Perera, A. Dar, Larry Stitt, Edward Yu, Sachi Voruganti, Pauline Truong Feb 1998

Does Delay In Breast Irradiation Following Conservative Breast Surgery In Node-Negative Breast Cancer Patients Have An Impact On Risk Of Recurrence?, Olga Vujovic, Francisco Perera, A. Dar, Larry Stitt, Edward Yu, Sachi Voruganti, Pauline Truong

Edward Yu

PURPOSE: This retrospective review was conducted to determine if delay in the start of radiotherapy after definitive breast surgery had any detrimental effect on local recurrence or disease-free survival in node-negative breast cancer patients. METHODS AND MATERIALS: A total of 568 patients with T1-T2, N0 breast cancer were treated with breast-conserving surgery and breast irradiation, without adjuvant systemic therapy between January 1, 1985 and December 31, 1992, at the London Regional Cancer Centre. Adjuvant breast irradiation consisted either of 50 Gy in 25 fractions or 40 Gy in 15 or 16 fractions, followed by a boost of 10 Gy or …


Superior Vena Cava Obstruction In Small-Cell Lung Cancer, Roscoe Chan, A. Dar, Edward Yu, Larry Stitt, Francis Whiston, Pauline Truong, Mark Vincent, Walter Kocha May 1997

Superior Vena Cava Obstruction In Small-Cell Lung Cancer, Roscoe Chan, A. Dar, Edward Yu, Larry Stitt, Francis Whiston, Pauline Truong, Mark Vincent, Walter Kocha

Edward Yu

PURPOSE: To identify prognostic or treatment factors influencing the response of superior vena cava obstruction (SVCO), time to SVCO recurrence, and overall survival of SCLC patients with SVCO at presentation; and to assess the role of retreatment in patients with SVCO at recurrent or persistent disease. METHODS AND MATERIALS: Between January 1983 and November 1993, 76 consecutive patients who had small-cell lung cancer (SCLC) with SVCO were treated in our institution. Analysis was done according to the disease status at diagnosis of SVCO. The first analysis concerned a group of 50 patients who had SVCO at initial presentation. The second …


Impact Of Radiation Therapy Fraction Size On Local Control Of Early Glottic Carcinoma, Edward Yu, George Shenouda, Marie Beaudet, Martin Black Jan 1997

Impact Of Radiation Therapy Fraction Size On Local Control Of Early Glottic Carcinoma, Edward Yu, George Shenouda, Marie Beaudet, Martin Black

Edward Yu

Purpose: Different radiotherapy fractionation schedules were used over a 10-year period to treat patients with early squamous cell carcinoma of the vocal cords at McGill University. A retrospective analysis was performed to study the effect of fraction size on local control in this group of patients. Methods and materials: A total of 126 previously untreated patients with T1 invasive squamous cell carcinoma of the true vocal cords were irradiated between January 1978 and December 1988 in the Department of Radiation Oncology at McGill University. All patients received megavoltage irradiation, 94 patients received daily fractions > 2 Gy (64 patients received 50 …


Vitamin D And Parotid Gland Function In The Rat, C. Peterfy, A. Tenenhouse, E. Yu Mar 1988

Vitamin D And Parotid Gland Function In The Rat, C. Peterfy, A. Tenenhouse, E. Yu

Edward Yu

1. We previously reported that parotid gland secretion is decreased in rats deprived of vitamin D (Glijer, Peterfy & Tenenhouse, 1985). In the present study we examine whether this effect is a direct result of the absence of vitamin D or due to the secondary systemic effects of vitamin D deficiency. 2. Offspring of rats maintained on a calcium-supplemented (1.2%), vitamin-D-deficient diet were weaned onto the same diet and examined after 8 weeks. Using this method it was possible to maintain serum calcium and parathyroid hormone concentrations within normal limits. Serum 25-hydroxyvitamin D (25(OH)D3) was not detectable, but 1,25-dihydroxyvitamin D …


The Role Of Biogenic Amines In The Regulation Of Exocrine Gland Function: A Possible Mechanism For The Pathogenesis Of Cystic Fibrosis, A. Tenenhouse, E. Yu Dec 1983

The Role Of Biogenic Amines In The Regulation Of Exocrine Gland Function: A Possible Mechanism For The Pathogenesis Of Cystic Fibrosis, A. Tenenhouse, E. Yu

Edward Yu

No abstract provided.


Uptake, Storage And Secretion Of 5-Hydroxytryptamine And Its Amino Acid Precursor By Dispersed Rat Pancreas Acinar Cells, Ligia Stern, A. Tenenhouse, E. Yu Jun 1983

Uptake, Storage And Secretion Of 5-Hydroxytryptamine And Its Amino Acid Precursor By Dispersed Rat Pancreas Acinar Cells, Ligia Stern, A. Tenenhouse, E. Yu

Edward Yu

Rat pancreas acinar cells contain 5-hydroxytryptamine (5-HT; 10.86 +/- 2.52 ng/i.u. amylase), all of which can be accounted for by the 5-HT recovered from the zymogen granule fraction of these cells (10.70 +/- 3.06 ng/i.u. amylase). When incubated with [14C]5-HT dispersed acinar cells take up the amine and concentrate it in zymogen granules. These cells will also take up [14C]5-HTP (5-hydroxytryptophan), decarboxylate it and store the [14C]5-HT so produced in zymogen granules. 5-HTP itself is not taken up by the granules. 5-HT is incorporated into zymogen granules early in their formation; no amine is accumulated by mature zymogen granules and …