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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.e., PERCIST, Porceddu, Hopkins, NI-RADS, modified Deauville, and Cuneo) were included in this review. Each SIC is evaluated in the context of 8 desired traits of a standardized reporting system. RESULTS: Two SICs have societal endorsements (i.e., PERCIST, NI-RADS); four can be used in the evaluation of locoregional and systemic disease (i.e., PERCIST, Hopkins, NI-RADS, Cuneo), and four have specific categories for equivocal imaging results (i.e., Porceddu, NI-RADS, modified Deauville, and Cuneo). All demonstrated areas for future improvement in the context of the 8 desired traits. CONCLUSION: Multiple SICs have been developed for and demonstrated value in HNSCC post-treatment imaging; however, these systems remain underutilized. Selecting an SIC with features that best match the needs of one's practice is expected to maximize the likelihood of successful implementation.
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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. Mitochondrial imaging with 99mTc-sestamibi single-photon emission computed tomography/CT is a cost-effective means of non-invasively identifying oncocytomas and other indolent renal masses. On the other end of the spectrum, carbonic anhydrase IX agents, most notably the monoclonal antibody girentuximab - which can be labeled with positron emission tomography radionuclides such as zirconium-89 - are effective at identifying renal masses that are likely to be aggressive clear cell renal cell carcinomas. Renal mass biopsy, which has a relatively high non-diagnostic rate and does not definitively characterize many oncocytic neoplasms, nonetheless may play an important role in any algorithm targeted to renal mass risk stratification. The combination of molecular imaging and biopsy in selected patients with other advanced imaging methods, such as artificial intelligence/machine learning and the abstraction of radiomics features, offers the optimal way forward for maximization of the information to be gained from risk stratification of indeterminate renal masses. With the proper application of those methods, inappropriately aggressive therapy for benign and indolent renal masses may be curtailed.
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Neoplasias Renais , Imagem Molecular , Humanos , Neoplasias Renais/diagnóstico por imagem , Imagem Molecular/métodos , Medição de Risco , Carcinoma de Células Renais/diagnóstico por imagem , Adenoma Oxífilo/diagnóstico por imagem , Compostos Radiofarmacêuticos , Anticorpos MonoclonaisRESUMO
Endometriosis is a common cause of infertility, pelvic pain, and dysmenorrhea and there are prior case reports of lesion detection using an 18F-fluoroestradiol (FES) tracer with positron emission tomography (PET). We aimed to further investigate the use of the FES tracer in the context of PET-magnetic resonance (PET-MR) imaging. We administered FES to 6 patients and then imaged them using a Siemens mMR PET-MR scanner. Each patient was taken to surgery within 30 days after imaging, and surgical visualization served as the gold-standard for diagnosis. PET did not prove to be as sensitive as MR (50% per-patient sensitivity versus 67% per-patient and 35% versus 48% per-lesion), and did not show any additional sites over and above MR. When MR was used to localize lesions on PET after imaging, there was insufficient evidence of an association between total tracer uptake and reported pain intensity (P=0.25). FES PET-MR offers no additional value to MR for endometriosis.
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PURPOSE: Indeterminate renal masses are increasingly incidentally found on cross-sectional imaging. 99mTc-sestamibi single-photon emission computed tomography/computed tomography (SPECT/CT) scans can be used to identify oncocytomas and oncocytic renal neoplasms, including a subset of chromophobe renal cell carcinomas (chRCCs), which are viewed as false-positive. PROCEDURE: Patients imaged with renal sestamibi scans between 2014 and 2023 were reviewed. Those patients with solitary tumors that were originally classified as chRCC were included in the analysis. Imaging with SPECT/CT from the liver dome down had been carried out 75 min after the administration of 925 MBq of 99mTc-sestamibi. All available H&E and immunostained slides were re-reviewed and classified according to WHO 2022 criteria. Confirmatory immunohistochemical stains were performed in tumors considered morphologically suspicious for non-chRCC entities. RESULT: A total of 18 patients with solitary tumors were included in the final analysis. 13/18 (72.2%) tumors in this cohort remained classified as chRCC, with 4/18 (22.2%) being eosinophilic-variant chRCC. The reclassified tumors (5/18 [27.8%]) included 2/18 (11.1%) low-grade oncocytic tumor (LOT), 1/18 (5.5%) eosinophilic vacuolated tumor (EVT), and 2/18 (11.1%) unclassified low-grade oncocytic neoplasms. As such, only 2/9 (22.2%) qualitatively "hot" tumors were chRCC other than eosinophilic-variant and only 1/9 (11.1%) "cold" tumors was a histology other than chRCC. CONCLUSION: Based on current histopathologic classification methods, it is likely that the "false-positive" rate of uptake on renal sestamibi scans with chRCC has been over-stated. Further study is warranted to better refine the optimal utility of renal sestamibi scans for non-invasive risk stratification of indeterminate renal masses.
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ABSTRACT: 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. Further study is needed to best understand the effects of these medications on FDG biodistribution.
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Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Humanos , Fluordesoxiglucose F18/farmacocinética , Insulina , Peptídeos Semelhantes ao Glucagon/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peptídeo 1 Semelhante ao Glucagon , Masculino , Pessoa de Meia-Idade , FemininoRESUMO
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. Prominent among these is the family of fibroblast-activation protein-targeted agents that interact with the tumor microenvironment and may show superiority to 2-deoxy-2-[18F]fluoro-d-glucose in a subset of different tumor histologies. Additionally, carbonic anhydrase IX (CAIX) inhibitors are directed at clear cell renal cell carcinoma, which has long lacked an effective PET imaging agent. Those CAIX agents may also have utility in hypoxic tumors. Pentixafor, which binds to a transmembrane receptor, may similarly allow for visualization by PET of low-grade lymphomas, as well as being a second agent for multiple myeloma that opens theranostic possibilities. There are new adrenergic agents aimed at providing a PET-visible replacement to the single-photon-emitting radiotracer meta-[123I]iodobenzylguanidine (MIBG). Finally, in response to a major development in oncologic chemotherapy, there are new radiotracers targeted at assessing the suitability or use of immunotherapeutic agents. All of these and the existing evidence for their utility are discussed.
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ABSTRACT: Prostate cancer (PCa) is the most common noncutaneous malignancy in men. Until recent years, accurate imaging of men with newly diagnosed PCa, or recurrent or low-volume metastatic disease, was limited. Further, therapeutic options for men with advanced, metastatic, castration-resistant disease were increasingly limited as a result of increasing numbers of systemic therapies being combined in the upfront metastatic setting. The advent of urea-based, small-molecule inhibitors of prostate-specific membrane antigen (PSMA) has partially addressed those shortcomings in diagnosis and therapy of PCa. On the diagnostic side, there are multiple pivotal phase III trials with several different agents having demonstrated utility in the initial staging setting, with generally modest sensitivity but very high specificity for determining otherwise-occult pelvic nodal involvement. That latter statistic drives the utility of the scan by allowing imaging interpreters to read with very high sensitivity while maintaining a robust specificity. Other pivotal phase III trials have demonstrated high detection efficiency in patients with biochemical failure, with high positive predictive value at the lesion level, opening up possible new avenues of therapy such as metastasis-directed therapy. Beyond the diagnostic aspects of PSMA-targeted radiotracers, the same urea-based chemical scaffolds can be altered to deliver therapeutic isotopes to PCa cells that express PSMA. To date, one such agent, when combined with best standard-of-care therapy, has demonstrated an ability to improve overall survival, progression-free survival, and freedom from skeletal events relative to best standard-of-care therapy alone in men with metastatic, castration-resistant PCa who are post chemotherapy. Within the current milieu, there are a number of important future directions including the use of artificial intelligence to better leverage diagnostic findings, further medicinal chemistry refinements to the urea-based structure that may allow improved tumor targeting and decreased toxicities, and the incorporation of new radionuclides that may better balance efficacy with toxicities than those nuclides that are available.
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Antígenos de Superfície , Glutamato Carboxipeptidase II , Neoplasias da Próstata , Compostos Radiofarmacêuticos , Humanos , Masculino , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/uso terapêutico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Glutamato Carboxipeptidase II/metabolismo , Glutamato Carboxipeptidase II/antagonistas & inibidores , Antígenos de Superfície/metabolismoRESUMO
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. In combination with the rise of artificial intelligence, our ability to derive imaging biomarkers that are associated with treatment selection, response assessment, and overall patient prognostication will only improve.
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Carcinoma de Células Renais , Carcinoma de Células de Transição , Neoplasias Renais , Neoplasias da Bexiga Urinária , Neoplasias Urológicas , Humanos , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/secundário , Fluordesoxiglucose F18 , Carcinoma de Células de Transição/diagnóstico por imagem , Inteligência Artificial , Neoplasias da Bexiga Urinária/terapia , Rim , Neoplasias Urológicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Tomografia por Emissão de Pósitrons/métodos , Neoplasias Renais/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia ComputadorizadaRESUMO
This study aimed to assess the accuracy of intraprostatic tumor volume measurements on prostate-specific membrane antigen-targeted 18F-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. Methods: Twenty-five men with clinically localized, high-risk prostate cancer were imaged with 18F-DCFPyL PET/CT before radical prostatectomy. The tumor volumes and tumor-to-prostate ratios (TPRs) of dominant intraprostatic foci of uptake were determined using semiautomatic segmentation (applying SUVmax percentage [SUV%] thresholds of SUV30%-SUV70%), adaptive segmentation (using adaptive segmentation percentage [A%] thresholds of A30%-A70%), and manual contouring. The histopathologic tumor volume (TV-Histo) served as the reference standard. The significance of differences between TV-Histo and PET-based tumor volume were assessed using the paired-sample Wilcoxon signed-rank test. The Spearman correlation coefficient was used to establish the strength of the association between TV-Histo and PET-derived tumor volume. Results: Median TV-Histo was 2.03 cm3 (interquartile ratio [IQR], 1.16-3.36 cm3), and median TPR was 10.16%. The adaptive method with an A40% threshold most closely determined the tumor volume, with a median difference of +0.19 (IQR, -0.71 to +2.01) and a median relative difference of +7.6%. The paired-sample Wilcoxon test showed no significant difference in PET-derived tumor volume and TV-Histo using A40%, A50%, SUV40%, and SUV50% threshold segmentation algorithms (P > 0.05). For both threshold-based segmentation methods, use of higher thresholds (e.g., SUV60% or SUV70% and A50%-A70%) resulted in underestimation of tumor volumes, and use of lower thresholds (e.g., SUV30% or SUV40% and A30%) resulted in overestimation of tumor volumes relative to TV-Histo and TPR. Manual segmentation overestimated the tumor volume, with a median difference of +2.49 (IQR, 0.42-4.11) and a median relative difference of +130%. Conclusion: Segmentation of intraprostatic tumor volume and TPR with an adaptive segmentation approach most closely approximates TV-Histo. This information might be used to guide the primary treatment of men with clinically localized, high-risk prostate cancer.
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Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Próstata/patologia , Neoplasias da Próstata/patologia , Prostatectomia , AlgoritmosRESUMO
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-[18F]fluoroestradiol (FES) and 12-[18F]fluoro-furanyl-nor-progesterone (FFNP)] in individuals with and without endometriosis. We also aimed to determine if menstrual cycle phase and/or the presence of endometriosis affected the uptake of these radiotracers. PROCEDURES: Rhesus macaques with either clinically diagnosed endometriosis (n = 6) or no endometriosis (n = 4) underwent PET/CT scans with FES. A subset of the animals also underwent PET/CT scans with FFNP. Standard uptake values corrected for body weight (SUVs) were obtained for each radiotracer in target and background tissues (e.g., intestinal). We performed repeated measure analysis of variance tests to determine how uterine and background uptake differed with scan time, phase of the menstrual cycle, and disease state. RESULTS: Abdominopelvic PET/CT could not resolve small, individual endometriotic lesions. However, macaques with endometriosis displayed higher uterine uptake compared to those without the disorder. Radiotracer uptake differed by menstrual cycle phase with increased uterine uptake of both radiotracers in the proliferative phase of the menstrual cycle. Background intestinal uptake of FFNP increased over time after infusion, but only during the proliferative phase. CONCLUSIONS: PET/CT with FES and FFNP support the concept that ER and PR levels are altered in individuals with endometriosis. This highlights the impact of the disease on typical reproductive tract function and may provide a novel pathway for the identification of individuals with endometriosis.
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Endometriose , Progestinas , Humanos , Feminino , Animais , Macaca mulatta/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Endometriose/metabolismo , Estrogênios , Receptores de Estrogênio/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Receptores de Progesterona/metabolismo , Útero/metabolismo , EstradiolRESUMO
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 (Macaca mulatta) 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. Procedures: Macaques with either clinically diagnosed endometriosis (n = 6) or no endometriosis (n = 4) underwent abdominopelvic PET/CT scans with FES. A subset of these animals also underwent PET/CT scans with FFNP. Standard uptake values corrected for body weight (SUVbw) were obtained for each radiotracer in target and background tissues (i.e., intestinal and muscle). We performed repeated measure analysis of variance tests to determine how uterine and background uptake differed with scan time, phase of the menstrual cycle, and disease state. Results: PET/CT could not resolve small, individual endometriotic lesions. However, uterine uptake of both radiotracers was elevated in the proliferative phase compared to the secretory phase of the menstrual cycle. Intestinal uptake exhibited greater variation during the proliferative phase compared to the secretory phase. Further, intestinal uptake of FFNP increases as the scan progresses, but only during the proliferative phase. Muscle uptake did not differ with menstrual phase or radiotracer type. Lastly, macaques with endometriosis displayed higher uterine uptake of FES compared to those without endometriosis. Conclusions: PET/CT with FES and FFNP support the concept that ER and PR levels are altered in individuals with endometriosis. This highlights the impact of the disease on typical reproductive tract function and may provide a novel pathway for the identification of individuals with endometriosis.
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[18F]DCFPyL is increasingly used for prostate-specific membrane antigen (PSMA) mediated imaging of men with biochemically recurrent prostate cancer (BRPCa). In this meta-analysis, which is updated with the addition of multiple new studies, including the definitive phase III CONDOR trial, we discuss the detection efficiency of [18F]DCFPyL in BRPCa patients. PubMed was searched on 29 September 2022. Studies evaluating the diagnostic performance of [18F]DCFPyL among patients with BRPCa were included. The overall pooled detection rate with a 95% confidence interval (95% CI) was calculated among all included studies and stratified among patients with PSA ≥ 2 vs. <2 ng/mL and with PSA ≥ 0.5 vs. <0.5 ng/mL. The association of detection efficiency with pooled PSA doubling time from two studies was calculated. Seventeen manuscripts, including 2252 patients, met the inclusion criteria and were used for data extraction. A previous meta-analysis reported that the pooled detection rate was 0.81 (95% CI: 0.77-0.85), while our study showed a pooled overall detection rate of 0.73 (95% CI: 0.66-0.79). An increased proportion of positive scans were found in patients with PSA ≥ 2 vs. <2 ng/mL and PSA ≥ 0.5 vs. <0.5 ng/mL. No significant difference was found in detection efficiency between those with PSA doubling time ≥ 12 vs. <12 months. Detection efficiency is statistically related to serum PSA levels but not to PSA doubling time based on available data. The detection efficiency of [18F]DCFPyL in men with BRPCa has trended down since a previous meta-analysis, which may reflect increasingly stringent inclusion criteria for studies over time.
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Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Masculino , Humanos , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico por imagemRESUMO
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. We assessed tryptophan and glucose metabolism by performing baseline C11-labeled α-methyl tryptophan (C11-AMT) and fluorodeoxyglucose (FDG) PET imaging of tumor lesions in a prospective clinical trial of pembrolizumab in MM (clinicaltrials.gov, NCT03089606). We found higher protein expression of all TMEs and LAT1 in melanoma cells than tumor-infiltrating lymphocytes (TILs) within MM tumors (n = 68). Melanoma cell-specific TPH1 and LAT1 expressions were significantly anti-correlated with TIL presence in MM. High melanoma cell-specific LAT1 and low IDO1 expression were associated with worse overall survival (OS) in MM. Exploratory optimal cutpoint survival analysis of pretreatment 'high' vs. 'low' C11-AMT SUVmax of the hottest tumor lesion per patient revealed that the 'low' C11-AMT SUVmax was associated with longer progression-free survival in our clinical trial (n = 26). We saw no such trends with pretreatment FDG PET SUVmax. Treatment of melanoma cell lines with telotristat, a TPH1 inhibitor, increased IDO expression and kynurenine production in addition to suppression of serotonin production. High melanoma tryptophan metabolism is a poor predictor of pembrolizumab response and an adverse prognostic factor. Serotoninergic but not kynurenine pathway activation may be significant. Melanoma cells outcompete adjacent TILs, eventually depriving the latter of an essential amino acid.
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Melanoma , Triptofano , Humanos , Triptofano/metabolismo , Triptofano/farmacologia , Fluordesoxiglucose F18 , Estudos Prospectivos , Cinurenina/metabolismo , Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Glucose , Melanoma Maligno CutâneoRESUMO
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. METHOD: A total of 169 students were enrolled over a period of 3 years, 55 before (2017-2018) and 114 (2018-2020) after the introduction of the symposium. Anonymous course evaluations were collected from all students. In addition, 240 fourth-year medical students who also attended symposium lectures received satisfaction surveys in 2019 and 2020. RESULTS: All (169/169, 100%) students taking the course evaluated it. Overall evaluation scores rose from 8.3/10 to 9.0/10 post-symposia. Among student satisfaction surveys, 89/240 (37%) specifically commented on symposia; 91% (80/89) of those found symposia very or extremely informative. 29/71 (41%) of all residents were able to participate in the symposia, 20/29 in multiple years throughout residency, allowing them to fulfill the Accreditation Council for Graduate Medical Education interpersonal and communication skills core competencies and meet scholarly activity requirements. CONCLUSION: Near-peer teaching in the form of resident-taught interactive didactics grouped in symposia can have a positive outcome on medical student satisfaction.
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INTRODUCTION: Currently, there is a lack of consensus on the fixed dosage of RAI to be administered for this purpose between the main guideline frameworks set forth by the American Thyroid Association (ATA), Society of Nuclear Medicine and Molecular Imaging (SNMMI), European Association of Nuclear Medicine (EANM) and the European Thyroid Association (ETA). In this retrospective study, we will investigate the effectiveness of using a standard dose of 15 mCi ±10% of RAI in the treatment of Graves'. METHODS: A retrospective chart review was conducted for the period between 1 May 2014 and 2 September 2020, to identify patients diagnosed with hyperthyroidism due to Graves' disease. The patients were grouped based on outcome and assessed for the efficacy of the dosage of 15 mCi ±10% of RAI in a successful treatment. RESULTS: Sixty-seven patients were identified that met the inclusion criteria between 1 May 2014 and 2 September 2020. Of the 67 RAI ablations; 60 patients became hypothyroid [60/67, (89.55%)], 2 euthyroid [2/67, (2.99%)] and 5 remained hyperthyroid [5/67, (7.46%)]. CONCLUSIONS: For the treatment of Graves' disease, the use of a standard low dose of 15 mCi ±10% has a high success rate without additional measurements or calculations beyond a standard planar image and 24-h uptake %. The adoption of a standard low dose of 15 mCi of I-131 across institutional guidelines would streamline dosage questions and eliminate the need to determine the weight of the thyroid for calculations in all RAI treatments for hyperthyroidism caused by Graves' disease.
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Doença de Graves , Hipertireoidismo , Humanos , Radioisótopos do Iodo/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Doença de Graves/radioterapia , Hipertireoidismo/radioterapiaRESUMO
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 (82Rb) rubidium PET/CT or technetium-99m (99mTc) 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. We found 43 SPECT/CT and 18 PET/CT studies which fit the desired criteria. Of these, 7 SPECT/CT studies and 2 PET/CT studies demonstrated the renal mass on at least one of the two sets of CT images (rest or stress); if not visible, most commonly the tumor was either out of the field of view or had already been removed. Of these, 6 SPECT/CT and 2 PET/CT studies demonstrated a malignancy. Cardiac SPECT/CT and PET/CT images demonstrate incidental renal masses with a non-negligible frequency, and CT images should be carefully examined.
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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. The patient is right hand dominant and reported no traumatic events, inflammation, infection, or extraneous use of the left arm. The patient did report "soreness" of the extremity starting approximately 24 hours post injection which continued to the time of the study.
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Background Chest tumors are often found incidentally on cardiac scans; we aimed to describe the findings of rubidium (Rb) in incidentally discovered extracardiac tumors. Materials and Methods We reviewed a database of cardiac Rb scans performed over a period of 11 years and identified those with a previously unsuspected malignancy seen on the plane of section. We then measured maximum standard uptake value for each of the tumors, as well as background lung, liver, mediastinum, and body wall. In cases where fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) was available, we compared Rb results with FDG PET/CT. Results We identified 63 patients meeting criteria including full visualization of a tumor of at least 1.0 cm with no prior treatment. Of these patients, 17 had breast, 36 had lung, and 10 had miscellaneous other tumors. We selected patients with either breast or lung tumors for further analysis. Overall uptake was relatively stable between rest and stress but lower than FDG PET/CT; it was generally low and similar to blood pool. There was a small but statistically significant correlation between estrogen receptor positivity and Rb uptake in breast tumors. There was a stable pattern of uptake in background tissues, with liver being greater than mediastinal blood pool, which in turn was more avid than lung, which was more avid than subcutaneous body wall tissues. Lung showed a noticeable tendency toward increased uptake in dependent regions, likely reflecting low-level atelectasis. Conclusion Uptake was stable between rest and stress but low relative to FDG PET/CT; some correlations with receptors suggest it may be useful in molecular imaging.
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OBJECTIVE: The aim of this study was to determine whether quantitative methods could aid in the evaluation of post-treatment head and neck scans, particularly taking human papillomavirus status into account. METHODS: Clinical readings of positron emission tomography/computed tomography scans as well as standardized uptake value (SUV)max (and other metrics) of nodes visible on PET conducted on a total of 172 patients with head and neck squamous cell cancer were examined. Locoregional recurrence at 2 years was assessed. In total 88 of these patients had close enough follow-up to determine whether individual nodes were positive or negative, and 233 nodes on these patients were compared to surgical pathology notes or follow-up (if no path was available). RESULTS: General negative predictive value (NPV) of complete response was 93% and an equivocal response was 89%; focusing on nodal recurrence, NPV was found to be 97% and positive predictive value (PPV) 46% if equivocal reads were treated as negative and NPV 98% and PPV 16% if equivocal reads were treated as positive. Using SUVmax of the hottest node with a cutoff of 3.4 gave NPV 97% and PPV 26%; a direct re-read (using 2 observers) gave NPV 98% and PPV 32% if equivocal reads were treated as negative, and NPV 99% and PPV 18% if equivocal reads were treated as positive. Using other first-order radiomics data such as SD and skewness did not improve this. CONCLUSIONS: Quantitative data such as SUVmax does not show additional value over qualitative evaluation of response to chemoradiation in head and neck tumors.
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Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Quimiorradioterapia , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagemRESUMO
Breast imaging, with its unique patient-facing, multimodality, and multidisciplinary workflow, offers opportunities to engage medical students enrolled in a general radiology rotation and to highlight the role of the radiologist in patient care. At a time when breast radiologists face unprecedented challenges in delivering safe and efficient imaging services, however, accommodating larger numbers of medical students can overwhelm reading rooms, dilute meaningful learning experiences for the student, and place further demands on faculty. In order to meet the students' and clinician educators' needs, Neher's one-minute preceptor teaching strategy is used to create a high-yield learning environment in a short amount of time. In this model, the breast radiologist weaves together multiple impactful and varied learning experiences in only 8 to 12 total hours of structured student exposure during the 160-hour general radiology course. We describe our adaptation of this technique and the positive impact that a short breast imaging component had on our general radiology medical student rotation. This standardized curriculum is easily adaptable to a variety of learning styles. It contributes to medical students' understanding of the various facets of radiology through direct participation and exceeds education goals set forth by the Alliance of Medical Student Educators in Radiology. Students' evaluations of the general radiology rotation demonstrated a sharp uptick in the year following the adoption of the technique, and students' rotation final examination mean scores on the breast questions were higher for students who participated at least eight hours on service in the breast radiology clinic.