Radiation Medicine Commons^™

Fractionated Stereotactic Radiotherapy (Fsrt) For Symptomatic Who Grade 1 Cavernous Sinus Meningiomas: Long-Term Local Control, Clinical Response, And Toxicity Outcomes, Ryan Shah, Shray Jain, Nilanjan Haldar, Lauren A. Holt, Robert Walker, Christopher J Farrell, Md, Debanjan Haldar, James J. Evans, Gregory S. Alexander, Wenyin Shi

Department of Radiation Oncology Faculty Papers

PURPOSE: Cavernous sinus meningiomas represent a significant clinical challenge, given the high prevalence of neurological deficits and limited surgical options. Radiation therapy is often the preferred treatment. This study evaluates the effectiveness of fractionated stereotactic radiation therapy (fSRT) in achieving local control and symptomatic relief in patients with cavernous sinus meningiomas.

METHODS: This is a single-institution retrospective analysis of patients with symptomatic presumed WHO grade 1 cavernous sinus meningiomas treated with fSRT (1.8-2 Gy per fraction). Clinical data were collected by chart review. Kaplan-Meier curves were generated to assess local control. Clinical responses were evaluated for symptom improvement, stability, or …

Reirradiation Treatment Effects In The Clinic (Retec) Proposal - Proof Of Concept Based On Spinal Cord Dose Tolerance For Reirradiation With Stereotactic Body Radiotherapy, Jimm Grimm, Anand Mahadevan, Olusola Obayomi-Davies, Scott G. Soltys, Arjun Sahgal, Kristin J. Redmond, Michael T. Milano, Wolfgang A. Tomé, Kenneth Brooks, Scott Dodd, John Austin Vargo, Gopal Subedi, Jinyu Xue, Bisher Ebid, Felix Ehret, Byung-Han Andrew Rhieu, Christoph Fürweger, Rachel Grimm, Alexander Muacevic, Vitali Moiseenko, Shalom Kalnicki, Mark Mclaughlin, Lawrence R. Kleinberg, John R. Adler, Iris C. Gibbs

College of Health Professions Faculty Papers

BACKGROUND: Since the inception of spinal radiosurgery decades ago, the factors influencing spinal cord recovery have remained unclear. Elucidating these factors would aid in reirradiation planning and delivery. We describe modeling reirradiation normal tissue complication probabilities (NTCP) from compiled published data, akin to the collaborative Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) and High Dose per Fraction, Hypofractionated Treatment Effects in the Clinic (HyTEC) projects.

PURPOSE: Simple dose-time recovery factors for the spinal cord serve as a basis to propose the Reirradiation Treatment Effects in the Clinic (ReTEC) project. ReTEC aims to define human organ recovery factors …

Evaluation Of The Intempo Path Set For Cyberknife Prostate And Lung Sbrt: A Single-Institution Experience, Yingcui Jia, Lei Fu, Shari Rudoler, Eric Gressen, Yevgeniy Vinogradskiy, Qianyi Xu

Department of Radiation Oncology Faculty Papers

PURPOSE: The InTempo adaptive imaging system is an important component of the Accuray CyberKnife System, designed to enhance the system's ability to track and correct tumor motion during treatment. However, a limitation of this feature is the reduction of available nodes for treatment planning. The impact of a reduced number of nodes on the quality of InTempo-based treatment plans has not previously been evaluated. This retrospective study aims to compare the dosimetry of CyberKnife plans with and without The InTempo path set for both prostate and lung stereotactic body radiotherapy (SBRT).

METHODS: This study included twelve consecutive prostate SBRT patients …

Evaluating Artifact-Free Four-Dimensional Computer Tomography With 16 Cm Detector Array, Inhwan Yeo, Wei Nie, Jiajin Fan, Mindy Joo, Michael Correa, Qianyi Xu

Department of Radiation Oncology Faculty Papers

PURPOSE: To evaluate a 16 cm-array axial four-dimensional computer tomography (4DCT) in comparison with a 4 cm-array 4DCT in the presence of respiration irregularity.

METHOD: Ten traces of lung tumor motion from CyberKnife treatments were imported to move the lung cylinder, containing a spherical target, of a phantom. Images were acquired for the lung that moved to each of the 10-positions/phases (1) step-wisely by nominal helical scan at each movement (ground truth), (2) continuously by 4D scan with the 16 cm array, and (3) the same with the 4 cm array, involving table shift. Irregularities, consisting of baseline shift and/or …

Early Outcomes Of Mr-Guided Sbrt For Patients With Recurrent Pancreatic Adenocarcinoma, Spencer Poiset, Sophia Shah, Louis Cappelli, Rani Anné, Karen Mooney, Maria Werner-Wasik, Talya Laufer, James Posey, Daniel Lin, Atrayee Mallick, Harish Lavu, Babar Bashir, Charles Yeo, Adam Mueller

Kimmel Cancer Center Faculty Papers

BACKGROUND: Local treatment options for locally recurrent pancreatic adenocarcinoma (LR-PAC) are limited, with median survival time (MST) of 9-13 months (mos) following recurrence. MRI-guided stereotactic body radiation therapy (MRgSBRT) provides the ability to dose escalate while sparing normal tissue. Here we report on the early outcomes of MRgSBRT for LR-PAC.

METHODS: Patients with prior resection of pancreatic adenocarcinoma with local recurrence treated with MRgSBRT at a single tertiary referral center from 5-2021 to 2-2023 were identified from our prospective database. MRgSBRT was delivered to 40-50 Gy in 4-5 fractions with target and OAR delineation per institutional standards. Endpoints included local …

Novel Frameless Linac Radiosurgery Solution For Uveal Melanoma, Louis Cappelli, Mehak Khan, Sudheshna Vemula, Christina Hum, Haisong Lui, Yan Yu, Yingxuan Chen, Yechi Zhang, Muhammad Sharif, Wenyin Shi

Department of Radiation Oncology Faculty Papers

INTRODUCTION: Radiation treatment has replaced enucleation as an organ-preservation treatment for patients with uveal melanoma (UM). We developed a novel non-invasive, frameless LINAC based solution for fractionated stereotactic radiosurgery (fSRS) treatment.

METHODS: We designed and constructed the a stereotactic ocular localization box that can be attached and indexed to a stereotactic LINAC tabletop. It contains adjustable LED lights as a gaze focus point and CCD camera for monitoring of the patient's eye position. The device also has 6 infrared spheres compatible with the ExacTRAC IGRT system. Treatment plans were developed using iPLAN Dose version 4.5, with conformal dynamic arcs and …

Fiducial Markers Allow Accurate And Reproducible Delivery Of Liver Stereotactic Body Radiation Therapy, Marina Moskalenko, Bernard L. Jones, Adam Mueller, Shirley Lewis, Jay C. Shiao, Sara J. Zakem, Tyler P. Robin, Karyn A. Goodman

Department of Radiation Oncology Faculty Papers

Fiducial markers are utilized for image guided radiotherapy (IGRT) alignment during the delivery of liver stereotactic body radiosurgery (SBRT). There are limited data demonstrating the impact of matching fiducials on the accuracy of liver SBRT. This study quantifies the benefit of fiducial-based alignment and improvements in inter-observer reliability. Nineteen patients with 24 liver lesions were treated with SBRT. Target localization was performed using fiducial markers on cone-beam computed tomography (CBCT). Each CBCT procedure was retrospectively realigned to match both the liver edge and fiducial markers. The shifts were recorded by seven independent observers. Inter-observer variability was analyzed by calculating the …

Multiagent Chemotherapy And Stereotactic Body Radiation Therapy In Patients With Unresectable Pancreatic Adenocarcinoma: A Prospective Nonrandomized Controlled Trial, Colin S Hill, Lauren Rosati, Hao Wang, Hua-Ling Tsai, Jin He, Amy Hacker-Prietz, Daniel A Laheru, Lei Zheng, Shuchi Sehgal, Vincent Bernard, Dung T Le, Timothy M Pawlik, Matthew J Weiss, Amol K Narang, Joseph M Herman

Faculty, Staff and Student Publications

PURPOSE: In a prospective multicenter study, gemcitabine monotherapy followed by stereotactic body radiation therapy (SBRT) was well tolerated with outcomes comparable to chemoradiation for locally advanced pancreatic cancer (LAPC). Recent trials have reported improved survival with multiagent chemotherapy (MA-CTX) alone. This prospective trial explored whether SBRT could be safely delivered after MA-CTX. Herein, we report the long-term outcomes of adding SBRT after MA-CTX in LAPC patients and evaluate whether genetic profiles of specimens obtained before SBRT influence outcomes.

METHODS AND MATERIALS: This prospective nonrandomized controlled phase 2 trial enrolled 44 LAPC and 4 locally recurrent patients after multidisciplinary evaluation between …

Fast Generation Of Lung Sbrt Plans With A Knowledge-Based Planning Model On Ring-Mounted Halcyon Linac, Justin Visak, Aaron Webster, Mark E. Bernard, Mahesh R. Kudrimoti, Marcus E. Randall, Ronald C. Mcgarry, Damodar Pokhrel

Radiation Medicine Faculty Publications

PURPOSE: To demonstrate fast treatment planning feasibility of stereotactic body radiation therapy (SBRT) for centrally located lung tumors on Halcyon Linac via a previously validated knowledge-based planning (KBP) model to support offline adaptive radiotherapy.

MATERIALS/METHODS: Twenty previously treated non-coplanar volumetric-modulated arc therapy (VMAT) lung SBRT plans (c-Truebeam) on SBRT-dedicated C-arm Truebeam Linac were selected. Patients received 50 Gy in five fractions. c-Truebeam plans were re-optimized for Halcyon manually (m-Halcyon) and with KBP model (k-Halcyon). Both m-Halcyon and k-Halcyon plans were normalized for identical or better target coverage than clinical c-Truebeam …

Predicting The Effect Of Indirect Cell Kill In The Treatment Of Multiple Brain Metastases Via Single-Isocenter/Multitarget Volumetric Modulated Arc Therapy Stereotactic Radiosurgery, Allison N. Palmiero, Denise Fabian, Marcus E. Randall, William St. Clair, Damodar Pokhrel

Radiation Medicine Faculty Publications

PURPOSE: Due to spatial uncertainty, patient setup errors are of major concern for radiosurgery of multiple brain metastases (m-bm) when using single-isocenter/multitarget (SIMT) volumetric modulated arc therapy (VMAT) techniques. However, recent clinical outcome studies show high rates of tumor local control for SIMT-VMAT. In addition to direct cell kill (DCK), another possible explanation includes the effects of indirect cell kill (ICK) via devascularization for a single dose of 15 Gy or more and by inducing a radiation immune intratumor response. This study quantifies the role of indirect cell death in dosimetric errors as a function of spatial patient setup uncertainty …

An Analytical Expression For R50% Dependent On Ptv Surface Area And Volume: A Cranial Srs Comparison, Dharmin D. Desai, Ellis Lee Johnson, Ivan L. Cordrey

Radiation Medicine Faculty Publications

The intermediate dose spill for a stereotactic radiosurgery (SRS) plan can be quantified with the metric R50%, defined as the 50% isodose cloud volume (V_IDC50%) divided by the volume of the planning target volume (PTV). By coupling sound physical principles with the basic definition of R50%, we derive an analytical expression for R50% for a spherical PTV. Our analytical expression depends on three quantities: the surface area of PTV (SA_PTV), the volume of PTV (V_PTV), and the distance of dose drop-off to 50% (Δr). The value of ∆r was obtained from a simple set …

Targeting Accuracy Considerations For Simultaneous Tumor Treating Fields Antimitotic Therapy During Robotic Hypofractionated Radiation Therapy., Sharmi Biswas, Irina Kapitanova, Sabrina Divekar, Jimm Grimm, Ian J Butterwick, Daniel Garren, Lawrence R Kleinberg, Kristin J Redmond, Michel Lacroix, Anand Mahadevan, Kenneth M Forster

College of Health Professions Faculty Papers

Purpose: Tumor treating fields (TTFields) is a novel antimitotic treatment that was first proven effective for glioblastoma multiforme, now with trials for several extracranial indications underway. Several studies focused on concurrent TTFields therapy with radiation in the same time period, but were not given simultaneously. This study evaluates the targeting accuracy of simultaneous radiation therapy while TTFields arrays are in place and powered on, ensuring that radiation does not interfere with TTFields and TTFields does not interfere with radiation. This is one of several options to enable TTFields to begin several weeks sooner, and opens potential for synergistic effects of …

A Novel And Clinically Useful Dynamic Conformal Arc (Dca)-Based Vmat Planning Technique For Lung Sbrt, Damodar Pokhrel, Justin Visak, Lana Sanford

Radiation Medicine Faculty Publications

PURPOSE: Volumetric modulated arc therapy (VMAT) is gaining popularity for stereotactic treatment of lung lesions for medically inoperable patients. Due to multiple beamlets in delivery of highly modulated VMAT plans, there are dose delivery uncertainties associated with small-field dosimetry error and interplay effects with small lesions. We describe and compare a clinically useful dynamic conformal arc (DCA)-based VMAT (d-VMAT) technique for lung SBRT using flattening filter free (FFF) beams to minimize these effects.

MATERIALS AND METHODS: Ten solitary early-stage I-II non-small-cell lung cancer (NSCLC) patients were treated with a single dose of 30 Gy using 3-6 non-coplanar VMAT arcs (clinical …

Successful Stereotactic Radiotherapy Of Meningiomas In A Patient With Cowden Syndrome: A Case Report, Christian Fernandez, Md, Corey Savard, Christopher J Farrell, Md, Wenyin Shi

Department of Radiation Oncology Faculty Papers

Cowden's Syndrome (CS) is a rare disease with increased risk for several carcinomas. Experimental studies and limited case reports have described the negative effects of radiotherapy. A 35-yearold woman presented with newly diagnosed CS and multiple meningiomas. She underwent subtotal resection of a right petroclival meningioma to relieve brainstem compression and received adjuvant fractionated stereotactic radiotherapy 50 Gy in 25 fractions with minimal side effects. Twenty months post-operatively the patient presented with neurological deficits from progression of additional meningiomas. Craniotomy was performed and gross total resection was achieved for all sites of disease. Imaging five months after surgery demonstrated progressive …

Quality Of Life Outcomes Following Organ-Sparing Sbrt In Previously Irradiated Recurrent Head And Neck Cancer, E. Gogineni, I. Zhang, Z. Rana, M. Marrero, G. Gill, A. Sharma, A. C. Riegel, S. Teckie, M. Ghaly

Journal Articles

No abstract provided.