Medical Specialties Commons^™

A Novel Compact Microwave Radiometric Sensor To Noninvasively Track Deep Tissue Thermal Profiles, Paolo F. Maccarini, Ankur Shah, Sharmila Y. Palani, Donald V. Pearce, Madhurima Vardhan, Paul R. Stauffer, Dario B. Rodrigues, Sara Salahi, Tiago R. Oliveira, Doug Reudink, Brent W. Snow

Department of Radiation Oncology Faculty Papers

Drawing from space technology to measure star temperature, we developed a noninvasive sensor to passively track thermal profiles in tissues well below the skin (>5cm). Ultra-low noise amplifiers combined with ultralow-loss switches in the 1- 2GHz band produce a high sensitivity multiband microwave radiometer. Due to the complex multilayer anatomy of human head, multiple sensing bands are needed to reconstruct the temperature of deep brain tissue. This is achieved by using a digitally controlled filter bank. To study its accuracy, the sensor was calibrated and tested in a multilayer phantom model of the human head with differential scalp and …

Optimization Of Chest Wall Hyperthermia Treatment Using A Virtual Human Chest Model, Dario B. Rodrigues, Mark D. Hurwitz, Paolo F. Maccarini, Paul R. Stauffer

Department of Radiation Oncology Faculty Papers

This work explores different coupling configurations (direct contact, air and water coupling) between a single 915 MHz waveguide applicator and human tissue in the setting of chest wall recurrence (CWR) of breast cancer. The objective is to treat chest wall tumours with microwave hyperthermia, while avoiding hot spots in critical areas such as scars and ribs. The best coupling configuration was a customized 24×29 cm water bolus developed by our team. It helps the applicator deliver an effective field size of 268 cm2 at 1 cm depth and a penetration depth of 2-3 cm. Water bolus thickness can be adjusted …

Quantifying Unnecessary Normal Tissue Complication Risks Due To Suboptimal Planning: A Secondary Study Of Rtog 0126., Kevin L. Moore, Rachel Schmidt, Vitali Moiseenko, Lindsey A. Olsen, Jun Tan, Ying Xiao, James Galvin, Stephanie Pugh, Michael J Seider, Adam P. Dicker, Walter Bosch, Jeff Michalski, Sasa Mutic

Department of Radiation Oncology Faculty Papers

PURPOSE: The purpose of this study was to quantify the frequency and clinical severity of quality deficiencies in intensity modulated radiation therapy (IMRT) planning in the Radiation Therapy Oncology Group 0126 protocol.

METHODS AND MATERIALS: A total of 219 IMRT patients from the high-dose arm (79.2 Gy) of RTOG 0126 were analyzed. To quantify plan quality, we used established knowledge-based methods for patient-specific dose-volume histogram (DVH) prediction of organs at risk and a Lyman-Kutcher-Burman (LKB) model for grade ≥2 rectal complications to convert DVHs into normal tissue complication probabilities (NTCPs). The LKB model was validated by fitting dose-response parameters relative …

Salvage Brachytherapy In Combination With Interstitial Hyperthermia For Locally Recurrent Prostate Carcinoma Following External Beam Radiation Therapy: A Prospective Phase Ii Study., Andrzej M Kukiełka, Vratislav Strnad, Paul R. Stauffer, Tomasz Dąbrowski, Marcin Hetnał, Damian Nahajowski, Tomasz Walasek, Piotr Brandys, Robert Matys

Department of Radiation Oncology Faculty Papers

Optimal treatment for patients with only local prostate cancer recurrence after external beam radiation therapy (EBRT) failure remains unclear. Possible curative treatments are radical prostatectomy, cryosurgery, and brachytherapy. Several single institution series proved that high-dose-rate brachytherapy (HDRBT) and pulsed-dose-rate brachytherapy (PDRBT) are reasonable options for this group of patients with acceptable levels of genitourinary and gastrointestinal toxicity. A standard dose prescription and scheme have not been established yet, and the literature presents a wide range of fractionation protocols. Furthermore, hyperthermia has shown the potential to enhance the efficacy of re-irradiation. Consequently, a prospective trial is urgently needed to attain clear …

Focused Ultrasound For Treatment Of Bone Tumours., Dario B. Rodrigues, Paul R. Stauffer, David Vrba, Mark Hurwitz, Md

Department of Radiation Oncology Faculty Papers

PURPOSE: Focused ultrasound (FUS) is a modality with rapidly expanding applications across the field of medicine. Treatment of bone lesions with FUS including both benign and malignant tumours has been an active area of investigation. Recently, as a result of a successful phase III trial, magnetic resonance-guided FUS is now a standardised option for treatment of painful bone metastases. This report reviews the clinical applications amenable to treatment with FUS and provides background on FUS and image guidance techniques, results of clinical studies, and future directions.

METHODS: A comprehensive literature search and review of abstracts presented at the recently completed …

Radiation Therapy After Radical Prostatectomy For Prostate Cancer: Evaluation Of Complications And Influence Of Radiation Timing On Outcomes In A Large, Population-Based Cohort., Sarah E Hegarty, Terry Hyslop, Adam Dicker Md, Phd, Timothy Showalter Md

Department of Radiation Oncology Faculty Papers

PURPOSE: To evaluate the influence of timing of salvage and adjuvant radiation therapy on outcomes after prostatectomy for prostate cancer.

METHODS: Using the Surveillance, Epidemiology, and End Results-Medicare linked database, we identified prostate cancer patients diagnosed during 1995-2007 who had one or more adverse pathological features after prostatectomy. The final cohort of 6,137 eligible patients included men who received prostatectomy alone (n = 4,509) or with adjuvant (n = 894) or salvage (n = 734) radiation therapy. Primary outcomes were genitourinary, gastrointestinal, and erectile dysfunction events and survival after treatment(s).

RESULTS: Radiation therapy after prostatectomy was associated with higher rates …

On Voxel-By-Voxel Accumulated Dose For Prostate Radiation Therapy Using Deformable Image Registration., Jialu Yu, Nicholas Hardcastle, Kyoungkeun Jeong, Edward T. Bender, Mark A. Ritter, Wolfgang A. Tomé

Department of Radiation Oncology Faculty Papers

Since delivered dose is rarely the same with planned, we calculated the delivered total dose to ten prostate radiotherapy patients treated with rectal balloons using deformable dose accumulation (DDA) and compared it with the planned dose. The patients were treated with TomoTherapy using two rectal balloon designs: five patients had the Radiadyne balloon (balloon A), and five patients had the EZ-EM balloon (balloon B). Prostate and rectal wall contours were outlined on each pre-treatment MVCT for all patients. Delivered fractional doses were calculated using the MVCT taken immediately prior to delivery. Dose grids were accumulated to the last MVCT using …

African American Men With Low-Grade Prostate Cancer Have Increased Disease Recurrence After Prostatectomy Compared With Caucasian Men., Kosj Yamoah, Curtiland Deville, Neha Vapiwala, Elaine Spangler, Charnita M. Zeigler-Johnson, Bruce Malkowicz, David I Lee, Michael Kattan, Adam P. Dicker, Timothy R. Rebbeck

Department of Radiation Oncology Faculty Papers

PURPOSE: To explore whether disparities in outcomes exist between African American (AA) and Caucasian (CS) men with low-grade prostate cancer and similar cancer of the prostate risk assessment-postsurgery (CAPRA-S) features following prostatectomy (RP).

METHODS: The overall cohort consisted of 1,265 men (234 AA and 1,031 CS) who met the National comprehensive cancer network criteria for low- to intermediate-risk prostate cancer and underwent RP between 1990 and 2012. We first evaluated whether clinical factors were associated with adverse pathologic outcomes and freedom from biochemical failure (FFbF) using the entire cohort. Next, we studied a subset of 705 men (112 AA and …