Improving Lung Stereotactic Body Radiation Therapy Dose Conformity Using a Simple Noncoplanar Volumetric Modulated Arc Therapy Technique.

This study characterizes lung stereotactic body radiation therapy (SBRT) dose conformity for a noncoplanar volumetric modulated arc therapy (VMAT) technique. Retrospectively, 288 previously treated lung SBRT cases were replanned using a VMAT technique of 2 ipsilateral 180° arcs separated by 30° couch angles. Two objectives were used for optimization: a lower objective to achieve planning target volume (PTV) coverage and a custom normal tissue objective to steepen the dose gradient.

Evaluation and failure analysis of four commercial deep learning-based autosegmentation software for abdominal organs at risk.

Purpose: Deep learning-based segmentation of organs-at-risk (OAR) is emerging to become mainstream in clinical practice because of the superior performance over atlas and model-based autocontouring methods. While several commercial deep learning-based autosegmentation solutions are now available, the implementation of these tools is still at such a primitive stage that acceptance criteria are underdeveloped due to a lack of knowledge about the systems' segmentation tendencies and failure modes. As the starting point of the iterative process of clinical implementation, this study focuses on the outlier analysis of four commercial autocontouring tools for the abdominal OARs.

Establishment of Twinning Partnership to Improve Pediatric Radiotherapy Outcomes Globally.

Purpose: Pediatric radiotherapy is a necessary and challenging component of oncologic care for children in low- and middle-income countries (LMICs). Collaboration between institutions in LMICs and high-income countries (HICs) has been shown to be effective in improving oncologic treatment outcomes; however, literature regarding pediatric radiotherapy twinning partnerships is limited.

Methods: Emory University has a long-standing twinning collaboration with Tikur Anbessa Specialized Hospital (TASH) for certain medical specialties.

Implementation of a Novel Chart Rounds Application to Facilitate Peer Review in a Virtual Academic Environment.

Purpose: Peer review in the form of chart rounds is a critical component of quality assurance and safety in radiation therapy treatments. Radiation therapy departments have undergone significant changes that impose challenges to meaningful review, including institutional growth and increasing use of virtual environment. We discuss the implementation of a novel chart rounds (NCR) format and application adapted to modern peer review needs at a single high-volume multisite National Cancer Institute designated cancer center.

Evaluating Pareto optimal tradeoffs for hippocampal avoidance whole brain radiotherapy with knowledge-based multicriteria optimization.

The goal of this study is to investigate the Pareto optimal tradeoffs between target coverage and hippocampal sparing using knowledge-based multicriteria optimization (MCO). Ten prior clinical cases were selected that were treated with hippocampal avoidance whole brain radiotherapy (HA-WBRT) using VMAT. A new, balanced plan was generated for each case using an in-house RapidPlan model in the Eclipse V16.

Technical note: Determining the applicability of a clinical knowledge-based learning model via prospective outlier detection.

Background: Knowledge-based planning (KBP) is increasingly implemented clinically because of its demonstrated ability to improve treatment planning efficiency and reduce plan quality variations. However, cases with large dose-volume histogram (DVH) prediction uncertainties may still need manual adjustments by the planner to achieve high plan quality.

Purpose: The purpose of this study is to develop a data-driven method to detect patients with high prediction uncertainties so that intentional effort is directed to these patients.

Implementation of a Knowledge-Based Treatment Planning Model for Cardiac-Sparing Lung Radiation Therapy.

Purpose: High radiation doses to the heart have been correlated with poor overall survival in patients receiving radiation therapy for stage III non-small cell lung cancer (NSCLC). We built a knowledge-based planning (KBP) tool to limit the dose to the heart during creation of volumetric modulated arc therapy (VMAT) treatment plans for patients being treated to 60 Gy in 30 fractions for stage III NSCLC.

Methods And Materials: A previous study at our institution retrospectively delineated intracardiac volumes and optimized VMAT treatment plans to reduce dose to these substructures and to the whole heart.

Phaeochromocytoma presenting as Takotsubo cardiomyopathy.

We report a case of a 72-year-old woman who presented with ST-elevation myocardial infarction (STEMI). However, coronary angiography showed unobstructed arteries while echocardiography (ECHO) showed severe left ventricular (LV) apical hypokinesia with ejection fraction (EF) of 25-30%. Seven months later she presented with a transient ischaemic attack and a repeat ECHO showed a normal EF.

MRI-based treatment planning for liver stereotactic body radiotherapy: validation of a deep learning-based synthetic CT generation method.

Objective: The purpose of this work is to develop and validate a learning-based method to derive electron density from routine anatomical MRI for potential MRI-based SBRT treatment planning.

Methods: We proposed to integrate dense block into cycle generative adversarial network (GAN) to effectively capture the relationship between the CT and MRI for CT synthesis. A cohort of 21 patients with co-registered CT and MR pairs were used to evaluate our proposed method by the leave-one-out cross-validation.

Sparing Cardiac Substructures With Optimized Volumetric Modulated Arc Therapy and Intensity Modulated Proton Therapy in Thoracic Radiation for Locally Advanced Non-small Cell Lung Cancer.

Purpose: Increasing radiation dose to the heart is associated with worse survival in stage III non-small cell lung cancer. We sought to evaluate the ability of optimized volumetric modulated arc therapy (VMAT) and intensity modulated proton therapy (IMPT) to spare cardiac substructures. We also wanted to determine how a cardiac optimization treatment planning algorithm influences dose distribution to other thoracic organs at risk (OARs).

Accuracy of 50-g glucose challenge test to detect International Association of Diabetes and Pregnancy Study Groups criteria-defined hyperglycemia.

Objectives: To determine the accuracy of the 50-g glucose challenge test (GCT) in detecting hyperglycemia in pregnancy (HIP) across a range of glucose thresholds relative to the International Association of Diabetes and Pregnancy Study Groups diagnostic criteria, and to determine the accuracy of the 50-g GCT among patients with different risk status.

Methods: The present prospective cohort study included women aged 18-45 years at 24-31  weeks of pregnancy who presented at the Mother and Child Hospital, Akure, Nigeria, between September 1, 2015, and February 29, 2016. Patients underwent the 50-g GCT followed by the 75-g oral glucose tolerance test (OGTT).

Development of Late Toxicities in Patients with Oral Tongue Cancer Treated with Surgical Resection and Adjuvant Radiation Therapy.

Objectives: The late effects of RT are not well reported in patients with oral tongue cancer (OTC). This study reports the incidence of late effects and factors associated with the development of late effects in OTC patients.

Methods: Patients with OTC treated in our institution from 2003 to 2013 were evaluated.

Simulating the Effect of Spectroscopic MRI as a Metric for Radiation Therapy Planning in Patients with Glioblastoma.

Due to glioblastoma's infiltrative nature, an optimal radiation therapy (RT) plan requires targeting infiltration not identified by anatomical magnetic resonance imaging (MRI). Here, high-resolution, whole-brain spectroscopic MRI (sMRI) is used to describe tumor infiltration alongside anatomical MRI and simulate the degree to which it modifies RT target planning. In 11 patients with glioblastoma, data from preRT sMRI scans were processed to give high-resolution, whole-brain metabolite maps normalized by contralateral white matter.

Thyroid autoimmunity in pregnant Nigerians.

Context: Thyroid autoimmunity is a recognized disorder in pregnancy and is associated with a number of adverse pregnancy outcomes.

Aim: This study set out to determine the relationship between pregnancy and thyroid autoimmunity in Nigerian women.

Settings And Design: This was an analytical cross-sectional study carried out in a tertiary hospital in South Western Nigeria with a total study population of 108 pregnant and 52 nonpregnant women.

Focal high-dose-rate brachytherapy: a dosimetric comparison of hemigland vs. conventional whole-gland treatment.

Purpose: To determine the utility of focal high-dose-rate brachytherapy for localized prostate cancer, we investigated the impact on target coverage and dose to organs at risk (OARs) with hemigland (HG) compared with whole-gland (WG) treatment.

Methods And Materials: A total of 10 WG implants were used to generate 10 WG and 20 HG (left and right) treatment plans optimized with the inverse planning simulation annealing algorithm using Oncentra MasterPlan (Nucletron B.V.

Electronic brachytherapy for postsurgical adjuvant vaginal cuff irradiation therapy in endometrial and cervical cancer: a retrospective study.

Purpose: A new platform for brachytherapy called electronic brachytherapy (EBT) has been developed, which uses a miniature X-ray source to generate low-energy radiation. A retrospective study of adverse events and clinical outcomes in patients treated with EBT to the vaginal cuff, either as monotherapy or in combination with external beam radiation therapy (EBRT), was conducted.

Methods And Materials: Medical records were reviewed from 16 patients treated with postoperative EBT for endometrial (n=13) or cervical cancer (n=3) between February 2009 and November 2010.

High-dose-rate prostate brachytherapy consistently results in high quality dosimetry.

Purpose: We performed a dosimetry analysis to determine how well the goals for clinical target volume coverage, dose homogeneity, and normal tissue dose constraints were achieved with high-dose-rate (HDR) prostate brachytherapy.

Methods And Materials: Cumulative dose-volume histograms for 208 consecutively treated HDR prostate brachytherapy implants were analyzed. Planning was based on ultrasound-guided catheter insertion and postoperative CT imaging; the contoured clinical target volume (CTV) was the prostate, a small margin, and the proximal seminal vesicles.