Comparison of standardized uptake value and standardized uptake lean body mass metrics in F-fluorodeoxyglucose positron emission tomography for assessing transformation in chronic lymphocytic leukemia and follicular lymphoma.

Background: The maximum standardized uptake value normalized to body weight (BW) (SUVmax) is a commonly used metric in F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging for assessing tumor aggressiveness and response to therapy. However, SUVmax is sensitive to changes in BW, potentially leading to inaccuracies in patients with cancer cachexia or obesity. The maximum standardized uptake value normalized to lean body mass (SULmax) has been proposed as a more reliable alternative, particularly in contexts where BW fluctuations are significant.

Theranostics 2.0: Target-driven, artificial intelligence-enabled cancer therapy across tumor types.

To date, prospective, pivotal clinical trials in the theranostic space have focused on specific disease states. Those include leveraging positron emission tomography (PET) findings to optimize the second-line use of Lu-DOTATATE in patients with metastatic and progressive neuroendocrine tumors or the use of prostate-specific membrane antigen (PSMA) PET findings to select patients with metastatic castration-resistant prostate cancer for treatment with Lu-PSMA-617. However, we are entering an era where a broader understanding of the expression patterns of a wide variety of targets is beginning to be understood.

Treatment Response Evaluation in Prostate Cancer Using PSMA PET/CT.

In recent years, there has been a headlong rush into the use of prostate-specific membrane antigen (PSMA)-targeted PET for the staging and restaging of men with prostate cancer (PC). To date, there have been regulatory approvals for PSMA PET for purposes of initial staging, recurrence, and establishing eligibility for PSMA-targeted radiopharmaceutical therapy. Conventional imaging modalities, including bone scan and CT, are inadequate for identifying sites of PC in a variety of clinical scenarios.

A Look to the Future: Potential Theranostic Applications in Head and Neck Tumors.

Theranostics, the practice of using a diagnostic radiopharmaceutical to guide radiotherapy with a chemically identical (or nearly identical) therapeutic radiopharmaceutical, is an exciting new field under development within the auspices of nuclear medicine. We aim to provide a narrative review of the areas of theranostics use and development which are occurring specifically in the head and neck, with attention to the therapeutic use of existing diagnostically used radiotracers such as agents that target prostate-specific membrane antigen (PSMA) and somatostatin receptors (e.g.

Lack of effect of renal function on uptake of 99m Tc-sestamibi in renal masses.

Objective: The appropriate clinical management of indeterminate small renal masses can be improved based on accurate risk stratification. This study aimed to investigate the impact of renal function on the uptake of technetium-99m ( 99m Tc)-sestamibi, a widely available imaging agent that can be utilized to identify oncocytomas and other benign/indolent renal masses.

Methods: A retrospective cohort study was conducted, involving 100 consecutive patients who underwent 99m Tc-sestamibi single-photon emission computed tomography/computed tomography.

Radiographic Response Assessments and Standardized Imaging Interpretation Criteria in Head and Neck Cancer on FDG PET/CT: A Narrative Review.

Introduction: There is growing interest in the development and application of standardized imaging criteria (SIC), to minimize variability and improve the reproducibility of image interpretation in head and neck squamous cell carcinoma (HNSCC).

Methods: "Squamous cell carcinoma" AND "standardized interpretation criteria" OR "radiographic response assessment" were searched using PubMed and Google Scholar for articles published between 2009 and 2024, returning 56 publications. After abstract review, 18 were selected for further evaluation, and 6 different SICs (i.

Molecular imaging for non-invasive risk stratification of renal masses.

Anatomic imaging with contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) has long been the mainstay of renal mass characterization. However, those modalities are often unable to adequately characterize indeterminate, solid, enhancing renal masses - with some exceptions, such as the development of the clear-cell likelihood score on multi-parametric MRI. As such, molecular imaging approaches have gained traction as an alternative to anatomic imaging.

Metastatic Adenoid Cystic Carcinoma of the Bartholin Gland.

Adenoid cystic carcinoma (ACC) of the Bartholin gland is an exceedingly rare neoplasm. A 56-year-old woman with remote ACC resection (plus neoadjuvant chemoradiation and adjuvant chemotherapy) presented to an outside institution with shortness of breath. CT showed bilateral pulmonary nodules and mediastinal lymphadenopathy.

FDG PET in a Patient on a GLP-1 Agonist/Insulin Secretagogue.

With the increase in use of GLP-1 receptor agonists such as semaglutide (Ozempic, Wegovy, Rybelsus) in the population, nuclear medicine physicians should be aware of the possibility of nondiagnostic FDG PET scans due to these medications, which work partly by increasing insulin secretion. We demonstrate a case where a patient's use of such a medication presumptively led to muscular and myocardial uptake, complicating scan interpretation considerably. Clinicians should be aware of the presence of these drugs and their potential effect on biodistribution in FDG PET.

The cutting edge: Promising oncology radiotracers in clinical development.

Molecular imaging moves forward with the development of new imaging agents, and among these are new radiotracers for nuclear medicine applications, particularly positron emission tomography (PET). A number of new targets are becoming accessible for use in oncologic applications. In this review, major new radiotracers in clinical development are discussed.

PET/Computed Tomography Transformation of Oncology: Kidney and Urinary Tract Cancers.

Renal cell carcinoma (RCC) and urothelial carcinoma (UC) are two of the most common genitourinary malignancies. 2-deoxy-2-[18F]fluoro-d-glucose (18F-FDG) can play an important role in the evaluation of patients with RCC and UC. In addition to the clinical utility of 18F-FDG PET to evaluate for metastatic RCC or UC, the shift in molecular imaging to focus on specific ligand-receptor interactions should provide novel diagnostic and therapeutic opportunities in genitourinary malignancies.

Uterine Uptake of Estrogen and Progestogen-Based Radiotracers in Rhesus Macaques with Endometriosis.

Purpose: Endometriosis is an estrogen-dependent disorder of menstruating primates where tissues similar to the inner lining of the uterus exist "ectopically" outside of the uterus. The ectopic endometrium, like the endometrium within the uterus, expresses estrogen receptors (ER) and progesterone receptors (PR) and undergoes hormone-dependent cell proliferation and bleeding each menstrual cycle. The goal of this study was to conduct abdominopelvic positron emission tomography (PET) scans with computed tomography (CT) imaging of rhesus macaques (Macaca mulatta) using radiotracers that target ER and PR [16α-[F]fluoroestradiol (FES) and 12-[F]fluoro-furanyl-nor-progesterone (FFNP)] in individuals with and without endometriosis.

Comparison of Multiple Segmentation Methods for Volumetric Delineation of Primary Prostate Cancer with Prostate-Specific Membrane Antigen-Targeted F-DCFPyL PET/CT.

This study aimed to assess the accuracy of intraprostatic tumor volume measurements on prostate-specific membrane antigen-targeted F-DCFPyL PET/CT made with various segmentation methods. An accurate understanding of tumor volumes versus segmentation techniques is critical for therapy planning, such as radiation dose volume determination and response assessment. Twenty-five men with clinically localized, high-risk prostate cancer were imaged with F-DCFPyL PET/CT before radical prostatectomy.

Prostate-Specific Membrane Antigen-Ligand Therapy: What the Radiologist Needs to Know.

The discovery and clinical development of radiolabeled small-molecule ligands targeting prostate-specific membrane antigen (PSMA) has had a profound influence on the field of nuclear medicine. Such agents have been successfully deployed for both imaging and therapeutic applications. In particular, PSMA radioligand therapy (PRLT) has been shown to be a life-prolonging therapy for men with metastatic, castration-resistant prostate cancer and has also brought nuclear medicine physicians and nuclear radiologists into the forefront of direct patient care.

Uterine uptake of estrogen and progestogen-based radiotracers in rhesus macaques with endometriosis.

Purpose: Few investigations have examined the uptake of radiotracers that target the prominent sex-steroid receptors in the uterus across the menstrual cycle and with disease state. We aimed to determine if uptake of the radiotracers that target estrogen and progesterone receptors (ER and PR) differ with the presence of endometriosis and/or across the menstrual cycle. We performed PET and computed tomography (CT) imaging procedures on rhesus macaques () using 16α-[18F]fluoroestradiol (FES) and 21-[18F]fluoro-furanyl-nor-progesterone (FFNP) in individuals with and without endometriosis in the proliferative and secretory phases of the menstrual cycle.

Increased tryptophan, but not increased glucose metabolism, predict resistance of pembrolizumab in stage III/IV melanoma.

Clinical trials of combined IDO/PD1 blockade in metastatic melanoma (MM) failed to show additional clinical benefit compared to PD1-alone inhibition. We reasoned that a tryptophan-metabolizing pathway other than the kynurenine one is essential. We immunohistochemically stained tissues along the nevus-to-MM progression pathway for tryptophan-metabolizing enzymes (TMEs; TPH1, TPH2, TDO2, IDO1) and the tryptophan transporter, LAT1.

Near-Peer Teaching in Radiology Symposia: A Success Story in Residents as Teachers.

Introduction: Peer learning and near-peer teaching have been described in many specialties, less so in Radiology. We present near-peer teaching whereby residents present a series of didactic sessions at the course outset in the form of "symposia" and perform a scholarly activity in the form of teaching. We aim to demonstrate how near-peer teaching in symposia front-loaded within an introductory radiology course can improve medical student satisfaction.

Incidental renal masses on SPECT/CT and PET/CT.

While the presence of incidental breast and lung masses on cardiac scans is well known, renal masses are often incidentally discovered as well on cardiac examinations, some of which are malignant. We searched the electronic medical record system over the past 18 years, since the system was installed, for patients with a cardiac rubidium-82 (Rb) rubidium PET/CT or technetium-99m (Tc) sestamibi SPECT/CT performed within 1 year of a renal-protocol CT or MR. Each PET/CT or SPECT/CT was examined for presence of a renal lesion on the attenuation-correction CT images.

Incidental findings on a Tc99m-SESTAMIBI parathyroid scan post COVID-19 vaccination.

We present a case of abnormal findings on a Tc99m-Sestamibi parathyroid scan, post COVID-19 vaccination. The patient is a 48-year-old female presenting for evaluation of hyperparathyroidism who received the mRNA-1273 Moderna (ModernaTX, Inc.) vaccine seven days prior to the scan.