Medicine and Health Sciences Commons^™

Dosimetric Planning Study Of Respiratory-Gated Volumetric Modulated Arc Therapy For Early-Stage Lung Cancer With Stereotactic Body Radiation Therapy, Ilma Xhaferllari, Jeff Chen, Michael Macfarlane, Edward Yu, Stewart Gaede

Edward Yu

Purpose: To evaluate the dosimetric potential of respiratory-gated volumetric modulated arc therapy (VMAT) to reduce the dose to normal lung when treating early-stage non-small cell lung cancer (NSCLC) with stereotactic body radiation therapy (SBRT). Methods and materials: Twenty patients with inoperable stage I/II NSCLC with motion greater than 5 mm were retrospectively planned with 4-dimensional computed tomography–based gated and nongated VMAT. Each plan was optimized using two 225° arcs with 10-MV flattening filter– free beams with maximum dose rate of 2400 MU/min. A host script was generated and used to optimize all 40 plans to minimize dosimetric bias. The main …

Prophylactic Cranial Irradiation For Patients With Limited-Stage Small-Cell Lung Cancer With Response To Chemoradiation, Patricia Tai, Avi Assouline, Kurian Joseph, Larry Stitt, Edward Yu

Edward Yu

Background Previous clinical studies have generally reported that prophylactic cranial irradiation (PCI) was given to patients with a complete response (CR) to chemotherapy and chest radiotherapy in limited-stage small-cell lung cancer (SCLC). It is not clear if those with incomplete response (IR) would benefit from PCI. Patients and Methods The Saskatchewan experience from 1981 through 2007 was reviewed. Patients were treated with chest radiotherapy and chemotherapy with or without PCI (typical doses: 2500 cGy in 10 fractions over 2 weeks, 3000 cGy in 15 fractions over 3 weeks, or 3000 cGy in 10 fractions over 2 weeks). Results There were …

The Impact Of Post-Mastectomy Radiation Therapy On Male Breast Cancer Patients--A Case Series, Edward Yu, Hiromichi Suzuki, Jawaid Younus, Tarek Elfiki, Larry Stitt, Gary Yau, Olga Vujovic, Francisco Perera, Michael Lock, Patricia Tai

Michael Lock

OBJECTIVE: To assess the impact of radiation management on male breast cancer (MBC) at London Regional Cancer Program (LRCP).

METHODS AND MATERIALS: Men with a diagnosis of breast cancer referred to LRCP were reviewed. The seventh American Joint Committee on Cancer staging system was used. Patients treated with and without post-mastectomy radiation therapy (PMRT) were analyzed. Disease-free survival (DFS) was defined as time duration from diagnosis to first recurrence. Overall survival (OS) was defined as time duration from pathologic diagnosis to death or last follow-up with any death defined as an event. Survival estimates were obtained using Kaplan-Meier methodology.

RESULTS: …

Mesothelioma - Epidemiology And Management, Patricia Tai, Edward Yu, Avi Assouline, Kurian Joseph

Edward Yu

Mesothelioma is an uncommon tumor. It has a latency period of 20-40 years. The most important risk factor is asbestos exposure. Prognosis of mesothelioma is generally poor with high case-fatality rate, and research to improve the outcome of this disease is on-going worldwide. Due to its rarity, management by a multidisciplinary team with experience is recommended. Carefully selected patients may benefit from tri-modality (surgery, radiotherapy and chemotherapy) treatment. The management of pleural and peritoneal mesothelioma is summarized in this review. Recent advances in chemotherapy and biologic response modifiers are promising.

The Impact Of Post-Mastectomy Radiation Therapy On Male Breast Cancer Patients--A Case Series, Edward Yu, Hiromichi Suzuki, Jawaid Younus, Tarek Elfiki, Larry Stitt, Gary Yau, Olga Vujovic, Francisco Perera, Michael Lock, Patricia Tai

Edward Yu

OBJECTIVE: To assess the impact of radiation management on male breast cancer (MBC) at London Regional Cancer Program (LRCP). METHODS AND MATERIALS: Men with a diagnosis of breast cancer referred to LRCP were reviewed. The seventh American Joint Committee on Cancer staging system was used. Patients treated with and without post-mastectomy radiation therapy (PMRT) were analyzed. Disease-free survival (DFS) was defined as time duration from diagnosis to first recurrence. Overall survival (OS) was defined as time duration from pathologic diagnosis to death or last follow-up with any death defined as an event. Survival estimates were obtained using Kaplan-Meier methodology. RESULTS: …

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 …

Post-Operative Extended Volume External Beam Radiation Therapy In High Risk Esophageal Cancer Patients: A Prospective Experience, E. Yu, P. Tai, J. Younus, R. Malthaner, P. Truong, L. Stitt, G. Rodrigues, R. Ash, R. Dar, B. Yaremko, A. Tomiak, B. Dingle, M. Sanatani, M. Vincent, W. Kocha, D. Fortin, R. Inculet

Edward Yu

Background and purpose: Extended volume external beam radiation therapy (RT) following esophagectomy is controversial. This prospective study evaluates the feasibility of extended volume RT treatment in high-risk esophagectomy patients with cervical anastomosis receiving post–operative combined chemo-radiation therapy. Patients and methods: From 2001-2006, 15 patients with resected esophageal cancer were prospectively accrued to this pilot study, to evaluate the adverse effects of extended volume RT. Eligibility criteria were pathologically proven esophageal malignancy, T3-4, N0-1, disease amenable to surgical resection and esophagectomy with or without resection margin involvement. Patients with distant metastases (M1) and patients treated with previous RT were excluded. All …

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 …

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

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

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 …

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 …