Development of a selective novel fluorescent substrate for sodium-dependent transporters.

Aim: To synthesize, characterize, and validate 6FGA, a fluorescent glucose modified with a Cyanine5.5 at carbon-6 position, for probing the function of sodium-dependent glucose transporters, SGLT1 and SGLT2.

Main Methods: The synthesis of fluorescent glucose analogue was achieved through "click chemistry" of Cyanine5.

The Use of Magnetic Resonance Imaging in Radiation Therapy Treatment Simulation and Planning.

Ever since its introduction as a diagnostic imaging tool the potential of magnetic resonance imaging (MRI) in radiation therapy (RT) treatment simulation and planning has been recognized. Recent technical advances have addressed many of the impediments to use of this technology and as a result have resulted in rapid and growing adoption of MRI in RT. The purpose of this article is to provide a broad review of the multiple uses of MR in the RT treatment simulation and planning process, identify several of the most used clinical scenarios in which MR is integral to the simulation and planning process, highlight existing limitations and provide multiple unmet needs thereby highlighting opportunities for the diagnostic MR imaging community to contribute and collaborate with our oncology colleagues.

Dose uncertainty due to needle-tip localization error in prostate seed implantation.

Purpose: This study quantified the dosimetric uncertainty caused by needle-tip detection errors in ultrasound images due to bevel-tip orientation differences, with respect to the location on template grid.

Material And Methods: Trans-rectal ultrasound (TRUS) system with physical template grid and 18-gauge bevel-tip brachytherapy needles were used. TRUS was set at 6.

Pattern of Radiotherapy Treatment in Low-Risk, Intermediate-Risk, and High-Risk Prostate Cancer Patients: Analysis of National Cancer Database.

Background: In this study, the utilization rates and survival outcomes of different radiotherapy techniques are compared in prostate cancer (PCa) patients stratified by risk group. Methods: We analyzed an extensive data set of N0, M0, non-surgical PCa patients diagnosed between 2004 and 2015 from the National Cancer Database (NCDB). Patients were grouped into six categories based on RT modality: an intensity-modulated radiation therapy (IMRT) group with brachytherapy (BT) boost, IMRT with/without IMRT boost, proton therapy, stereotactic body radiation therapy (SBRT), low-dose-rate brachytherapy (BT LDR), and high-dose-rate brachytherapy (BT HDR).

Abdominopelvic MR to CT registration using a synthetic CT intermediate.

Accurate coregistration of computed tomography (CT) and magnetic resonance (MR) imaging can provide clinically relevant and complementary information and can serve to facilitate multiple clinical tasks including surgical and radiation treatment planning, and generating a virtual Positron Emission Tomography (PET)/MR for the sites that do not have a PET/MR system available. Despite the long-standing interest in multimodality co-registration, a robust, routine clinical solution remains an unmet need. Part of the challenge may be the use of mutual information (MI) maximization and local phase difference (LPD) as similarity metrics, which have limited robustness, efficiency, and are difficult to optimize.

Effect of applicator removal from target volume for cervical cancer patients treated with Venezia high-dose-rate brachytherapy applicator.

Purpose: The volume of Venezia applicator with vaginal caps can be relatively large compared to target volumes. This study investigated the dosimetric and radiobiological effects of applicator volume removal for cervical cancer patients treated with Venezia (VZ) and tandem and split-ring (TSR) applicators used in the clinic.

Material And Methods: A total of 40 patients (101 plans) with stage IIA-IIIC cervical cancer were retrospectively reviewed.

Focal Prostate Stereotactic Body Radiation Therapy With Correlative Pathological and Radiographic-Based Treatment Planning.

Introduction: Advances in multiparametric MRI (mpMRI) combining anatomic and functional imaging can accurately identify foci of adenocarcinoma within the prostate, offering the possibility of partial gland therapy. We performed tandem prospective pilot trials to investigate the feasibility of focal prostate SBRT (f-SBRT) based on correlating diagnostic mpMRI and biopsies with confirmatory pathology in treatment planning.

Materials And Methods: Patients with pathologic focal Gleason 6-7 disease and a corresponding PIRADS 4-5 lesion on mpMRI underwent targeted and comprehensive biopsies using MRI/ultrasound fusion under electromagnetic sensor navigation.

Synthetic CT Generation of the Pelvis in Patients With Cervical Cancer: A Single Input Approach Using Generative Adversarial Network.

Multi-modality imaging constitutes a foundation of precision medicine, especially in oncology where reliable and rapid imaging techniques are needed in order to insure adequate diagnosis and treatment. In cervical cancer, precision oncology requires the acquisition of F-labeled 2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), magnetic resonance (MR), and computed tomography (CT) images. Thereafter, images are co-registered to derive electron density attributes required for FDG-PET attenuation correction and radiation therapy planning.

Final results of a dose escalation protocol of stereotactic body radiotherapy for poor surgical candidates with localized renal cell carcinoma.

Background And Purpose: We previously demonstrated the safety of doses up to 48 Gy in 4 fractions with stereotactic body radiotherapy (SBRT) in poor surgical candidates with localized renal cell carcinoma (RCC). In an additional expansion cohort, we aimed to assess the safety of further dose escalation to 48-60 Gy in 3 fractions.

Material And Methods: Patients were required to have localized RCC and be poor surgical candidates due to medical comorbidities.

Feasibility of improving patient's safety with in vivo dose tracking in intracavitary and interstitial HDR brachytherapy.

Purpose: The in vivo dosimetric monitoring in HDR brachytherapy is important for improving patient safety. However, there are very limited options available for clinical application. In this study, we present a new in vivo dose measurement system with a plastic scintillating detector (PSD) for GYN HDR brachytherapy.

Adjusting to the new reality: Evaluation of early practice pattern adaptations to the COVID-19 pandemic.

Objective: We aim to define national practice patterns to assess current clinical practice, anticipated delays and areas of concern that potentially could lead to deviations from the normal standard of care.

Methods: Anonymous surveys were emailed to members of the Society of Gynecologic Oncology (SGO). The spread of COVID-19 and its impact on gynecologic oncology care in terms of alterations to normal treatment patterns and anticipated challenges were assessed.

Transforming UTE-mDixon MR Abdomen-Pelvis Images Into CT by Jointly Leveraging Prior Knowledge and Partial Supervision.

Computed tomography (CT) provides information for diagnosis, PET attenuation correction (AC), and radiation treatment planning (RTP). Disadvantages of CT include poor soft tissue contrast and exposure to ionizing radiation. While MRI can overcome these disadvantages, it lacks the photon absorption information needed for PET AC and RTP.

mDixon-Based Synthetic CT Generation for PET Attenuation Correction on Abdomen and Pelvis Jointly Using Transfer Fuzzy Clustering and Active Learning-Based Classification.

We propose a new method for generating synthetic CT images from modified Dixon (mDixon) MR data. The synthetic CT is used for attenuation correction (AC) when reconstructing PET data on abdomen and pelvis. While MR does not intrinsically contain any information about photon attenuation, AC is needed in PET/MR systems in order to be quantitatively accurate and to meet qualification standards required for use in many multi-center trials.

Appropriate Methodology for EBRT and HDR Intracavitary/Interstitial Brachytherapy Dose Composite and Clinical Plan Evaluation for Patients With Cervical Cancer.

Purpose: This study assessed the appropriateness of full parameter addition (FPA) methods with respect to the 3-dimensional deformable dose composite method for evaluating combined external beam radiation therapy (EBRT) and intracavitary brachytherapy (ICBT).

Methods And Materials: A total of 22 patients who received EBRT and high-dose-rate ICBT were retrospectively evaluated. Split-ring and tandem applicators were used for all patients.

UTE-mDixon-based thorax synthetic CT generation.

Purpose: Accurate photon attenuation assessment from MR data remains an unmet challenge in the thorax due to tissue heterogeneity and the difficulty of MR lung imaging. As thoracic tissues encompass the whole physiologic range of photon absorption, large errors can occur when using, for example, a uniform, water-equivalent or a soft-tissue-only approximation. The purpose of this study was to introduce a method for voxel-wise thoracic synthetic CT (sCT) generation from MR data attenuation correction (AC) for PET/MR or for MR-only radiation treatment planning (RTP).

Comparison of multiparametric MRI-based and transrectal ultrasound-based preplans with intraoperative ultrasound-based planning for low dose rate interstitial prostate seed implantation.

Purpose: Transrectal ultrasound images are routinely acquired for low dose rate (LDR) prostate brachytherapy dosimetric preplanning (pTRUS), although diagnostic multiparametric magnetic resonance imaging (mpMRI) may serve this purpose as well. We compared the predictive abilities of TRUS vs MRI relative to intraoperative TRUS (iTRUS) to assess the role of mpMRI in brachytherapy preplanning.

Materials And Methods: Retrospective analysis was performed on 32 patients who underwent iTRUS-guided prostate LDR brachytherapy as either mono- or combination therapy.

Abdominal, multi-organ, auto-contouring method for online adaptive magnetic resonance guided radiotherapy: An intelligent, multi-level fusion approach.

Background: Manual contouring remains the most laborious task in radiation therapy planning and is a major barrier to implementing routine Magnetic Resonance Imaging (MRI) Guided Adaptive Radiation Therapy (MR-ART). To address this, we propose a new artificial intelligence-based, auto-contouring method for abdominal MR-ART modeled after human brain cognition for manual contouring.

Methods/materials: Our algorithm is based on two types of information flow, i.

Machine learning-based dual-energy CT parametric mapping.

The aim is to develop and evaluate machine learning methods for generating quantitative parametric maps of effective atomic number (Z), relative electron density (ρ ), mean excitation energy (I ), and relative stopping power (RSP) from clinical dual-energy CT data. The maps could be used for material identification and radiation dose calculation. Machine learning methods of historical centroid (HC), random forest (RF), and artificial neural networks (ANN) were used to learn the relationship between dual-energy CT input data and ideal output parametric maps calculated for phantoms from the known compositions of 13 tissue substitutes.

Reduction of seed motion using a bio-absorbable polymer coating during permanent prostate brachytherapy using a mick applicator technique.

Purpose: The addition of a braided bio-absorbable vicryl coating to the surface of radioactive seeds used for low dose rate (LDR) prostate brachytherapy is intended to reduce the incidence of seed movement and migration. Here, we present a single-institution study of the frequency and severity of seed slippage (initial seed movement) of coated seeds in comparison with uncoated seeds.

Methods: Forty-seven patients received permanent prostate brachytherapy, with either coated (n = 26) or uncoated (n = 21) seeds.

3T multiparametric MRI-guided high-dose-rate combined intracavitary and interstitial adaptive brachytherapy for the treatment of cervical cancer with a novel split-ring applicator.

Purpose: To evaluate the role of 3T-MRI-guided adaptive high-dose-rate (HDR) combined intracavitary and interstitial brachytherapy for cervical cancer using a novel intracavitary split-ring (ICSR) applicator adapter.

Methods And Materials: We retrospectively reviewed all HDR brachytherapy cases from 2013 to 2015 using an ICSR applicator. Initial optimization was performed using 3T multiparametric MRI (mpMRI) series with an applicator in place.

Evaluation of interfractional variation of organs and displacement of catheters during high-dose-rate interstitial brachytherapy for gynecologic malignancies.

Purpose: To investigate the dosimetric effects due to interfractional changes in catheter position and variation in patient's anatomy during the course of interstitial high-dose-rate (HDR) brachytherapy.

Methods And Materials: A total of 15 patients with either cervical or vaginal cancer underwent interstitial HDR brachytherapy. Interstitial catheters and fiducials were placed under fluoroscopy and intraoperative 3T MRI to confirm the desired catheter placement for adequate target volume coverage.

Outcomes and toxicities in patients treated with definitive focal therapy for primary prostate cancer: systematic review.

Aim: This systematic review summarizes the clinical data on focal therapy (FT) when used alone as definitive therapy for primary prostate cancer (PCa).

Methods: The protocol is detailed in the online PROSPERO database, registration No. CRD42014014765.

¹⁸F-FDG PET/CT for Monitoring of Treatment Response in Breast Cancer.

Changes in tumor metabolic activity have been shown to be an early indicator of treatment effectiveness for breast cancer, mainly in the neoadjuvant setting. The histopathologic response at the completion of chemotherapy has been used as the reference standard for assessment of the accuracy of (18)F-FDG PET in predicting a response during systemic treatment. Although a pathologic complete response (pCR) remains an important positive prognostic factor for an individual patient, a recent metaanalysis could validate pCR as a surrogate marker for patient outcomes only in aggressive breast cancer subtypes.