Utility of pre-procedural [Tc]TcMAA SPECT/CT Multicompartment Dosimetry for Treatment Planning of Y Glass microspheres in patients with Hepatocellular Carcinoma: comparison of anatomic versus [Tc]TcMAA-based Segmentation.

Purpose: Pre-treatment [Tc]TcMAA-based radioembolization treatment planning using multicompartment dosimetry involves the definition of the tumor and normal tissue compartments and calculation of the prescribed absorbed doses. The aim was to compare the real-world utility of anatomic and [Tc]TcMAA-based segmentation of tumor and normal tissue compartments.

Materials And Methods: Included patients had HCC treated by glass [Y]yttrium microspheres, ≥ 1 tumor, ≥ 3 cm diameter and [Tc]TcMAA SPECT/CT imaging before treatment.

SNMMI Clinical Trials Network Research Series for Technologists: An Introduction to Conducting Theranostic Clinical Trials.

This article is intended to introduce nuclear medicine technologists (NMTs) to the nuances of radiopharmaceutical therapy clinical trials. Here, we outline the potential roles and responsibilities of the NMT in clinical trials and provide context on different aspects of radionuclide therapy. The regulatory process involving investigational therapeutic radiopharmaceuticals is seldom taught to NMT students, nor is it included in the entry-level nuclear medicine certification examinations.

Y SIR-Spheres Activity Measurement with New SIROS D-Vial Delivery Kit.

A new Y SIR-Spheres delivery kit (SIROS D-vial and shield) has been introduced with a different physical form from the legacy V-Vial kit. Here, we establish the dose calibrator settings and exposure-rate-to-activity conversion factor to assay Y SIR-Spheres activity in the new SIROS kit. Eight D-vials with initial Y activities from 1.

Imageable Radioembolization Microspheres for Treatment of Unresectable Hepatocellular Carcinoma: Interim Results from a First-in-Human Trial.

Purpose: To determine 6-month interim safety, effectiveness, and multimodal imageability of imageable glass microsphere yttrium-90 (Y) radioembolization for unresectable hepatocellular carcinoma (HCC) in a first-in-human trial.

Materials And Methods: Imageable microspheres (Eye90 Microspheres; ABK Biomedical, Halifax, Nova Scotia, Canada), a U.S.

Resin-Based 90 Y Tumor Dose as a Predictor of Duration of Response and Survival in Patients With Surgically Unresectable Hepatocellular Carcinoma : A Prospective Single-Arm Study.

Background: Personalized dosimetry improves overall survival (OS) in patients with hepatocellular carcinoma (HCC) treated with glass 90 Y radioembolization. This study evaluated personalized tumor dose (TD) as a predictor of OS, progression-free survival (PFS), and local duration of response (DOR) in patients with surgically unresectable HCC treated with resin 90 Y radioembolization.

Patients And Methods: This prospective, single-center, single-arm clinical trial (NCT04172714) evaluated the efficacy of scout activity of resin 90 Y versus 99m Tc-MAA for treatment planning.

An international phantom study of inter-site variability in Technetium-99m image quantification: analyses from the TARGET radioembolization study.

Background: Personalised multi-compartment dosimetry based on [Tc]Tc-MAA is a valuable tool for planning Y radioembolization treatments. The establishment and effective application of dose-effect relationships in yttrium-90 (Y) radioembolization requires [Tc]Tc-MAA SPECT quantification ideally independent of clinical site. The purpose of this multi-centre phantom study was to evaluate inter-site variability of [Tc]Tc-MAA imaging and evaluate a standardised imaging protocol.

Direct comparison and reproducibility of two segmentation methods for multicompartment dosimetry: round robin study on radioembolization treatment planning in hepatocellular carcinoma.

Purpose: Investigate reproducibility of two segmentation methods for multicompartment dosimetry, including normal tissue absorbed dose (NTAD) and tumour absorbed dose (TAD), in hepatocellular carcinoma patients treated with yttrium-90 (Y) glass microspheres.

Methods: TARGET was a retrospective investigation in 209 patients with < 10 tumours per lobe and at least one tumour ≥ 3 cm ± portal vein thrombosis. Dosimetry was compared using two distinct segmentation methods: anatomic (CT/MRI-based) and count threshold-based on pre-procedural Tc-MAA SPECT.

Voxel-based dosimetry predicting treatment response and related toxicity in HCC patients treated with resin-based Y90 radioembolization: a prospective, single-arm study.

Background: There is an increasing body of evidence indicating Y90 dose thresholds for tumor response and treatment-related toxicity. These thresholds are poorly studied in resin Y90, particularly in hepatocellular carcinoma (HCC).

Purpose: To evaluate the efficacy of prospective voxel-based dosimetry for predicting treatment response and adverse events (AEs) in patients with HCC undergoing resin-based Y90 radioembolization.

Monte Carlo-derived Tc uptake quantification with commercial planar MBI: Tumor and breast activity concentrations.

Background: Current molecular breast imaging (MBI) images are limited to qualitative evaluation, not absolute measurement, of Tc uptake in benign and malignant breast tissues.

Purpose: This work assesses the accuracy of previously-published and newly-proposed tumor and normal breast tissue Tc uptake MBI measurements using simulations of a commercial dual-headed planar MBI system under typical clinical and acquisition protocols.

Methods: Quantification techniques were tested in over 4000 simulated acquisitions of spherical and ellipsoid tumors with clinically relevant uptake conditions using a validated Monte Carlo application of the GE Discovery NM750b system.

Clinical, dosimetric, and reporting considerations for Y-90 glass microspheres in hepatocellular carcinoma: updated 2022 recommendations from an international multidisciplinary working group.

Purpose: In light of recently published clinical reports and trials, the TheraSphere Global Dosimetry Steering Committee (DSC) reconvened to review new data and to update previously published clinical and dosimetric recommendations for the treatment of hepatocellular carcinoma (HCC).

Methods: The TheraSphere Global DSC is comprised of health care providers across multiple disciplines involved in the treatment of HCC with yttrium-90 (Y-90) glass microsphere-based transarterial radioembolization (TARE). Literature published between January 2019 and September 2021 was reviewed, discussed, and adjudicated by the Delphi method.

Accuracy and Safety of Scout Dose Resin Yttrium-90 Microspheres for Radioembolization Therapy Treatment Planning: A Prospective Single-Arm Clinical Trial.

Purpose: To compare the accuracy and safety of 0.56 GBq resin yttrium-90 (Y) (scoutY) microspheres with those of technetium-99m macroaggregated albumin (MAA) in predicting the therapeutic Y (RxY) dose for patients with hepatocellular carcinoma (HCC).

Materials And Methods: This prospective single-arm clinical trial (Clinicaltrials.

Single-Photon Emission Computed Tomographic Reverse Lymphatic Mapping for Groin Vascularized Lymph Node Transplant Planning.

Background: Superficial inguinal (groin) vascularized lymph node transplantation is the most common option for the treatment of lymphedema, particularly in combination with free abdominal flap breast reconstruction. This study examines the utility of single-photon emission computed tomographic (SPECT/CT) lymphoscintigraphy for lower extremity reverse lymphatic mapping in presurgical planning for groin vascularized lymph node transplantation and appraises the physiologic lymphatic drainage to the superficial inguinal lymph nodes.

Methods: All patients who underwent bilateral lower extremity SPECT/CT reverse lymphatic mapping over a 5-year period were included.

Factors modulating Tc-MAA planar lung dosimetry for Y radioembolization.

Purpose: To investigate the accuracy and biases of predicted lung shunt fraction (LSF) and lung dose (LD) calculations via Tc-macro-aggregated albumin ( Tc-MAA) planar imaging for treatment planning of Y-microsphere radioembolization.

Methods And Materials: LSFs in 52 planning and LDs in 44 treatment procedures were retrospectively calculated, in consecutive radioembolization patients over a 2 year interval, using Tc-MAA planar and SPECT/CT imaging. For each procedure, multiple planar LSFs and LDs were calculated using different: (1) contours, (2) views, (3) liver Tc-MAA shine-through compensations, and (4) lung mass estimations.

Organ-level internal dosimetry for intra-hepatic-arterial administration of Tc-macroaggregated albumin.

Purpose: There are no published data on organ doses following intra-hepatic-arterial administration of Tc-macroaggregated-albumin (IHA Tc-MAA) routinely used in Y-radioembolization treatment planning to assess intra- and extra-hepatic depositions and calculate lung-shunt-fraction (LSF). We propose a method to model the organ doses following IHA Tc-MAA that incorporates three in vivo constituent biodistributions, the Tc-MAA that escape the liver due to LSF, and the Tc-MAA dissociation fraction (DF).

Methods: The potential in vivo biodistributions for IHA Tc-MAA are: Liver-Only MAA with all activity sequestered in the liver (LSF = 0&DF = 0), Intravenous MAA with all activity transferred intravenously as Tc-MAA (LSF = 1&DF = 0), and Intravenous Pertechnetate with all activity is transferred intravenously as Tc-pertechnetate (LSF = 0&DF = 1).

The American Brachytherapy Society consensus statement for permanent implant brachytherapy using Yttrium-90 microsphere radioembolization for liver tumors.

Purpose: To develop a multidisciplinary consensus for high quality multidisciplinary implementation of brachytherapy using Yttrium-90 (Y) microspheres transarterial radioembolization (Y TARE) for primary and metastatic cancers in the liver.

Methods And Materials: Members of the American Brachytherapy Society (ABS) and colleagues with multidisciplinary expertise in liver tumor therapy formulated guidelines for Y TARE for unresectable primary liver malignancies and unresectable metastatic cancer to the liver. The consensus is provided on the most recent literature and clinical experience.

A global evaluation of advanced dosimetry in transarterial radioembolization of hepatocellular carcinoma with Yttrium-90: the TARGET study.

Purpose: To investigate the relationships between tumor absorbed dose (TAD) or normal tissue absorbed dose (NTAD) and clinical outcomes in hepatocellular carcinoma (HCC) treated with yttrium-90 glass microspheres.

Methods: TARGET was a retrospective investigation in 13 centers across eight countries. Key inclusion criteria: liver-dominant HCC with or without portal vein thrombosis, < 10 tumors per lobe (at least one ≥ 3 cm), Child-Pugh stage A/B7, BCLC stages A-C, and no prior intra-arterial treatment.

A prospective, multicenter, open-label, single-arm clinical trial design to evaluate the safety and efficacy of Y resin microspheres for the treatment of unresectable HCC: the DOORwaY90 (Duration Of Objective Response with arterial Ytrrium-90) study.

Background: Selective internal radiation therapy (SIRT) with yttrium-90 (Y) resin microspheres is an established locoregional treatment option for unresectable hepatocellular carcinoma (HCC), which delivers a lethal dose of radiation to hepatic tumors, while sparing surrounding healthy tissue. DOORwaY90 is a prospective, multicenter, open-label, single arm study, designed to evaluate the safety and effectiveness of Y resin microspheres as first-line treatment in patients with unresectable/unablatable HCC. It is unique in that it is the first study with resin microspheres to utilize a personalized Y dosimetry approach, and independent review for treatment planning and response assessment.

Precision dosimetry in yttrium-90 radioembolization through CT imaging of radiopaque microspheres in a rabbit liver model.

Purpose: To perform precision dosimetry in yttrium-90 radioembolization through CT imaging of radiopaque microspheres in a rabbit liver model and to compare extracted dose metrics to those produced from conventional PET-based dosimetry.

Materials And Methods: A CT calibration phantom was designed containing posts with nominal microsphere concentrations of 0.5 mg/mL, 5.

A Prospective Comparative Study of Using Ultrasonography, 4D-CT and Parathyroid Dual-Phase Scintigraphy with SPECT in Patients with Primary Hyperparathyroidism.

Thirty-one consecutive patients were included in this study who were planned for parathyroidectomy due to primary hyperparathyroidism. They were studied with US, 4D-CT and dual-phase scintigraphy including SPECT/CT, and possible adenomas were identified in each imaging modality. Imaging data were quantified with US, CT and SPECT.

A Prospective Phase II Study of Safety and Efficacy of Sorafenib Followed by Y Glass Microspheres for Patients with Advanced or Metastatic Hepatocellular Carcinoma.

Purpose: The most common cause of death in advanced/metastatic hepatocellular carcinoma (HCC) is liver failure due to tumor progression. While retrospective studies and meta-analyses of systemic therapy combined with liver-directed therapy have been performed, prospective studies of safety/efficacy of antiangiogenesis followed by intra-arterial therapies are lacking. We tested our hypothesis that sorafenib followed by yttrium 90 glass microspheres (Y GMs) is safe and that survival outcomes may improve by controlling hepatic tumors.

Reassessment of the lung dose limits for radioembolization.

Radioembolization, also known as selective internal radiation therapy (SIRT), is an established treatment for the management of patients with unresectable liver tumors. Advances in liver dosimetry and new knowledge about tumor dose-response relationships have helped promote the well-tolerated use of higher prescribed doses, consequently transitioning radioembolization from palliative to curative therapy. Lung dosimetry, unfortunately, has not seen the same advances in dose calculation methodology and renewed consensus in dose limits as normal liver and tumor dosimetry.