Radiographics : a review publication of the Radiological Society of North America, IncNiloufar Rafiei Alavi, Arti Gupta, Maryam Rahmani, Sindu Alexander, Ali Afsari, Mahbod Jafarvand Giglou, Shyam M Srinivas, Vahid Yaghmai
PURPOSE: Biliary atresia (BA) often requires liver transplantation despite Kasai portoenterostomy (KPE). The prognostic role of hepatobiliary scintigraphy remains unclear. METHODS: Twenty-three infants undergoing KPE between 2017 and 2024 were retrospectively analyzed. Patients without 6-h bowel activity on technetium-99 m PMT hepatobiliary scintigraphy underwent 24-h delayed imaging. The primary endpoint was jaundice clearance (total bilirubin < 2 mg/dL within 3 months). Ancillary analyses included an internally validated receiver operating characteristic (ROC) cutoff and correlation of the 24-h porta hepatis-to-hepatic surface (PH/HS) ratio with 1-year bilirubin, native liver survival (NLS), and portal plate bile duct diameter. RESULTS: Sixteen infants achieved jaundice clearance, and their 24-h PH/HS ratio was higher (1.20 vs. 1.11, p = 0.049). ROC analysis identified an exploratory cutoff of 1.15 (apparent area under the curve [AUC], 0.768; internally validated AUC, 0.670). Excluding patients transplanted within 1 year, the PH/HS ratio correlated inversely with 1-year bilirubin (r = - 0.720). NLS did not differ significantly between groups, and the association with portal plate bile duct diameter was weak. CONCLUSIONS: The 24-h PH/HS ratio was associated with post-KPE jaundice clearance. However, these findings remain preliminary and hypothesis-generating. As a noninvasive preoperative parameter beyond routine laboratory testing, the PH/HS ratio warrants prospective multicenter validation.
Journal of medical economicsPatrik Zamecnik, Jürgen Feuerstein, Michael Berghahn, Jelle Barentsz
BACKGROUND AND OBJECTIVE: Accurate nodal staging in intermediate- to high-risk prostate cancer (PCa) is crucial for treatment decisions. While extended pelvic lymph node dissection (ePLND) is the standard, it is invasive and has a low diagnostic yield. A 2019 analysis suggested that non-invasive imaging such as PSMA-PET/CT and ferumoxtran-enhanced macrophage-MRI (m-MRI) is cost-effective, but at the possible expense of a small QALY loss compared to ePLND, based on limited evidence. Recent Phase 3 trials have provided new data, prompting a reevaluation. Therefore, the aim of this article is to update a model with recent trial data to assess the cost-effectiveness of m-MRI and PSMA-PET/CT versus ePLND in Germany. MATERIAL AND METHODS: We adapted a Markov model to simulate lifetime outcomes for men with intermediate- to high-risk PCa from a German insurer's perspective, with costs updated to 2025 level. Diagnostic accuracy data were derived from recent multicenter trials. Costs and QALYs were calculated using a 3% discount rate. Sensitivity analyses tested uncertainties. A practical interactive online-tool is provided for clinical decision-making and research purposes, which can incorporate various input data (https://macrophage-mri.app). RESULTS: Both imaging options were dominant over ePLND (€37,855; 18.11 QALYs). PSMA-PET/CT was €7,869 cheaper and gained 0.800 QALYs; m-MRI was €9,985 cheaper and gained 0.990 QALYs. m-MRI was superior, saving €2,116 and gaining 0.19 QALYs over PSMA-PET/CT. The probabilistic analysis showed that m-MRI was optimal over 95% of the time at an €80,000/QALY threshold; the probability of PSMA-PET/CT being optimal was less than 5%. CONCLUSIONS: An imaging-first approach outperforms routine ePLND, with m-MRI as a cost-effective option. PSMA-PET/CT's low sensitivity limits its usefulness, though it is still cheaper than ePLND. These results support including m-MRI in guidelines for initial staging.
NeurologySung-Woo Kim, Myung Jun Lee, Jin Woo Kim, Jang Yoo, Han-Kyeol Kim, Jin Yong Hong, Mark Yoffe Liberman, Min Seok Baek
BACKGROUND AND OBJECTIVES: Parkinson disease (PD) is a progressive neurodegenerative disease in which gait impairment is a common and disabling clinical feature. We aimed to characterize the independent and mediated contributions of striatal dopamine transporter (DAT) availability and gray matter (GM) volume to quantitative gait impairment in de novo PD. METHODS: In this prospective study, we consecutively recruited patients with de novo PD fulfilling the UK Brain Bank clinical criteria and healthy controls (HCs) without focal neurologic symptoms and parkinsonism at Wonju Severance Christian Hospital. All participants underwent GAITRite-based gait analysis, and patients further underwent brain MRI for GM volumetry, 18F-FP-CIT PET for striatal DAT availability, and motor and cognitive assessments. After exploratory gait-related correlation analyses, causal mediation analyses tested whether the effects of neuroimaging biomarkers on gait parameters were mediated by cognition or motor symptom severity. RESULTS: A total of 122 patients with de novo PD (mean age, 69.66 years; 45.90% female) and 177 HCs (mean age, 72.07 years; 51.41% female) were enrolled. Compared with HCs, patients with PD showed slower velocity, shorter step/stride lengths, reduced swing and single-support time, increased double-support time, and greater dispersion across multiple gait domains. Limbic-related GM volumes were associated with step/stride lengths and temporal phase composition, and these associations were substantially mediated by global cognition (representative ACMEs [95% CIs] for stride length: posterior cingulate cortex, 1.9559 [0.5606-4.2238]; hippocampus, 3.6722 [1.0707-8.2118]; thalamus, 2.8794 [0.0408-7.2535]; amygdala, 4.9696 [1.8241-10.3405]; proportions mediated, 19%-50%). Lower putaminal DAT availability was associated with greater stance time and double-support time variability, whereas lower caudate DAT availability was associated with longer swing and single-support time and altered phase parameters. These associations were not significantly mediated by bradykinesia/rigidity scores; direct effects remained significant (ADEs [95% CIs]: caudate-swing time, -0.0237 [-0.0428 to -0.0086]; putamen-double-support time variability, -2.0249 [-3.1445 to -0.8835]). DISCUSSION: These findings support a dual-pathway model of gait regulation in patients with de novo PD, where striatal dopaminergic denervation directly affects gait rhythmicity, whereas limbic system atrophy affects gait through direct and cognition-mediated pathways. This medication-naïve cohort may limit generalizability to the broader PD spectrum.
Inorganic chemistryMou Chakraborty, Kevin K Lee, Abbie Hasson, Thines Kanagasundaram, Amanda Fears, Aohan Hu, Justin J Wilson, Daniel L J Thorek
Radiotheranostic agents combine targeted therapeutics and diagnostic imaging, offering more efficient and personalized treatment strategies. Positron emission tomography provides high sensitivity and quantitative accuracy; however, its integration with α-particle radiotherapy remains limited by the lack of chelators capable of stabilizing radionuclides with widely different ionic radii. 89Zr and 225Ac are promising radionuclides for PET imaging and targeted α-therapy, respectively, but require robust and versatile chelation strategies. Herein, we report stable coordination using the 18-membered macrocyclic dual size-selective chelator py2-macrodipa with [89Zr]Zr4+and [225Ac]Ac3+ ions. The chelator demonstrated efficient radiolabeling with both 89Zr and 225Ac, exhibiting 89Zr labeling efficiency comparable to the state-of-the-art chelator DFO at micromolar concentrations. The [89Zr][Zr(py2-macrodipa)]2+ complex showed high stability in human serum and in vivo, with minimal uptake in nonspecific tissues such as bone and other organs. Similarly, the [225Ac][Ac(py2-macrodipa)]+ complex displayed robust in vitro and in vivo stability along with a biodistribution clearance profile similar to its 89Zr analogue. In addition, a squaramide ethyl ester-conjugated bifunctional chelator (py2-macrodipa-sq) was synthesized for antibody conjugation and assessed using the PD-1 targeting antibody Opdivo. Both 89Zr- and 225Ac-labeled opdivo-py2-macrodipa-sq conjugates were obtained with >98% radiochemical purity and demonstrated high stability in vitro and in vivo. Although the therapeutic construct exhibited higher activity levels in blood and other organs than the diagnostic analogue, both cleared over time with similar distribution patterns and low bone uptake. These findings establish py2-macrodipa and its bifunctional derivative, py2-macrodipa-sq, as potential chelation platforms for the development of matched 89Zr/225Ac radiotheranostic agents, demonstrating stable and comparable in vivo behavior.
Clinical nuclear medicineMohammad Hadi Samadi, Pegah Sahafi, Ali Emadi Toghabeh, Hassan Kamali, Atena Aghaee
We report a rare case of a 40-year-old woman with longstanding craniofacial fibrous dysplasia involving the right maxilla, orbital cavity, and fronto-parietal bones. The patient underwent partial maxillary debulking 7 years ago for cosmetic reasons and orbital decompression 3 years ago, and is currently on long-term antiresorptive therapy. Bone scintigraphy with 99mTc-MDP showed multiple sites of increased osteoblastic activity. 99mTc-FAPI SPECT/CT also revealed focal uptake in craniofacial and other lesions, indicating active fibroblast proliferation. This is the first reported case of 99mTc-FAPI uptake in fibrous dysplasia, suggesting its value in evaluating fibrotic bone lesions.
BACKGROUND AND OBJECTIVES: Putamen dopamine depletion characterizes Parkinson disease (PD). Intraneuronal processes determining dopamine stores have not been systematically examined. This study explored relative contributions of dopamine synthesis, storage, and metabolism to control-PD differences. METHODS: We updated an intramural tabulation from 2002 to 2024 of postmortem putamen tissue contents of reactants, including the autotoxic dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL), from patients with PD and controls. Based on computational models applying first-order kinetics and equilibrium equations, we then compared estimated rates of dopamine synthesis through tyrosine hydroxylase (TH), L-aromatic-amino-acid decarboxylase, vesicular active uptake and passive leakage, exocytotic release and reuptake, and other intraneuronal processes. Results from the modeling were compared with those from in vivo 18F-DOPA PET. RESULTS: Postmortem data were analyzed from 13 patients with PD (median age 77 years, range 73-85 years) and 20 controls (median age 77 years, range 35-91 years). There was approximately a 98% decrease in putamen tissue dopamine in PD, and the concentration ratio of DOPAL/dopamine (DA) was approximately 9 times that of control. Applying the simplest kinetic model, vesicular sequestration was estimated to be decreased by 98.5% (0.073 vs 4.91 nmol/minute). Approximately 3-fold greater in vivo "washout" of putamen 18F-DOPA-derived radioactivity compared with controls also indicated attenuated vesicular storage in PD. According to the complete model, control-PD differences in intraneuronal reaction rates were in descending order of vesicular uptake ≈ vesicular leakage > exocytotic release ≈ neuronal reuptake > L-aromatic-amino-acid decarboxylase activity ≈ TH activity > other reactions. DISCUSSION: Convergent quantitative evidence points to a substantial vesicular storage defect in residual dopaminergic terminals in PD. This finding challenges the sufficiency of nigrostriatal dopaminergic denervation alone to account for the biochemical phenotype of PD and highlights vesicular dopamine handling as a critical determinant of putamen dopamine deficiency. The reaction rate estimates were drawn from published point values rather than fitted to an experimental data set, and so conventional goodness-of-fit regression statistics were not conducted. Because of the assumption of steady-state conditions for calculating reaction rates based on equilibrium equations, the model does not address the dynamics of disease pathogenesis over years but does provide a platform for further extension to disease progression. BRIEF SUMMARY: We estimated rates of reactions involved with the synthesis, storage, release, reuptake, and metabolism of dopamine in the putamen in PD and found that the main intraneuronal functional abnormality separating PD from controls was attenuated vesicular sequestration, implicating decreased vesicular uptake through the vesicular monoamine transporter and increased vesicular leakiness as key determinants of putamen dopamine deficiency in PD.
ACS applied bio materialsMarta Pomraenke, Julia Greiser, Olga Perkas, Lukas M Zehner, Valentin D Wegner, Nikolaus Gassler, Alexander S Mosig, Kerstin Huebner, Regine Schneider-Stock, N…
Animal models are utilized in the investigation of a variety of research questions in nuclear medicine. Radiopharmaceutics are usually tested in mouse, rat or chick chorioallantoic membrane (CAM) models and visualisation of their biodistribution is performed using dedicated small-animal PET/CT scanners. However, the limited availability of such scanners represents a significant bottleneck in preclinical imaging. To address this limitation, we explored an alternative animal model compatible with clinical imaging systems. The ostrich chorioallantoic membrane (CAM) was utilized as a platform for tumor xenografts, enabling imaging with a standard human PET/CT scanner. Growth conditions for tumor formation were established using human glioblastoma (U87) and breast cancer (MDA-MB-231) cell lines. Tumor visualization was achieved using 18F-fluorodeoxyglucose (18F-FDG), a widely used clinical PET tracer, and its pharmacodynamic behavior was assessed. Our findings demonstrate that the ostrich CAM tumor model is a feasible and efficient system for the rapid evaluation of diagnostic tracers. Importantly, tracer uptake and kinetics can be reliably assessed using a clinical PET/CT scanner. This approach highlights the potential of the ostrich embryonic model as a versatile and accessible preclinical platform for nuclear medicine research.
American journal of physiology. Endocrinology and metabolismLijuan Sun, Hui Jen Goh, Xinyan Bi, Priya Govindharajulu, Mya Thway Tint, Karen Mei-Ling Tan, Hong Pan, Bright Starling Emerald, Melvin Khee-Shing Leow
The relationship between circulating amino acids (AAs), particularly branched-chain amino acids (BCAAs), and brown adipose tissue (BAT) recruitment and their subsequent fate during thermogenesis remains poorly defined. We investigated the longitudinal changes and predictive role of serum AAs metabolism in 25 participants with overweight or obesity following a 12-wk BAT-activating intervention (curcumin supplementation and/or cold exposure). Participants were stratified into BAT responders (n = 8) and nonresponders (n = 17) via fusion 18-fluorine fluorodeoxyglucose positron emission tomography-magnetic resonance (18F-FDG PET/MR) imaging. BAT responders exhibited a significant systemic clearance of several AAs, including phenylalanine, glutamine, asparagine, and glycine, whereas nonresponders showed a significant increase in valine and total BCAAs. Multiple linear regression analysis identified baseline levels of total BCAAs (β = 0.81, P = 0.007) and glucogenic AAs (β = 0.65, P < 0.001) as independent positive predictors of BAT activity. Furthermore, the magnitude of BAT activation was inversely associated with the longitudinal change in these AAs, suggesting that activated BAT serves as a significant site for systemic AA clearance. We conclude that circulating branched-chain and glucogenic AAs are closely associated with the capacity for BAT recruitment and activation. The resulting enhanced metabolic demand transforms the activated BAT into an effective site for systemic AA clearance and improved metabolic homeostasis.NEW & NOTEWORTHY Elevated circulating branched-chain amino acids (BCAAs) are established biomarkers of metabolic dysfunction, but the regulatory role of human brown adipose tissue (BAT) remains unclear. We demonstrate that high baseline BCAA and glucogenic amino acid levels independently predict the capacity of BAT recruitment. Furthermore, successful BAT activation is associated with the systemic clearance of these metabolites. These findings suggest that BAT serves as a key regulator of amino acid homeostasis and represents a potential therapeutic target for addressing metabolic disorders in adults.
Metabolic disruption in the prefrontal cortex is closely associated with functional decline in cerebral small vessel disease (CSVD), especially among older adults. This study aimed to investigate both the separate and combined effects of aging and CSVD on prefrontal cortex metabolism. A total of 191 participants who underwent 18F-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging scanning were divided into four groups: middle-aged healthy control (HC) (n = 60), middle-aged CSVD patients (n = 52), older HC (n = 35) and older CSVD patients (n = 44). Age was categorized as middle-aged (40-59 years) and older (60-80 years), and enrolled CSVD cases were strictly diagnosed as white matter hyperintensities (WMH)-defined CSVD following standardized criteria. Main and interaction effects of aging and CSVD on prefrontal cortex metabolism were analyzed across three levels: local region, connectivity, and network, with multiple comparison correction applied. Significant interactions between aging and CSVD were identified in the relative mean standardized uptake value of the prefrontal cortex, as well as in global (clustering coefficient) and nodal properties (nodal clustering coefficient, nodal efficiency, and nodal local efficiency). Additionally, significant main effects of age and CSVD were observed on the prefrontal cortex' average standardized uptake value, whereas main effects of age were found on both global and nodal properties of the prefrontal metabolic network. These findings demonstrate altered prefrontal metabolic profiles associated with aging and WMH-defined CSVD. These observed metabolic patterns offer preliminary insights, and may guide future studies integrating comprehensive clinical assessments and longitudinal follow-up.
Current problems in cancerMargaret Locke, Charit Taneja, Mehdi Djekidel, Nagashree Seetharamu
BACKGROUND: Treatment decisions in advanced or metastatic differentiated thyroid cancer require comprehensive clinical, genomic, and imaging evaluations. FDG-PET and radioactive iodine (RAI) scans image different biological clones of tumor subsets and are frequently complementary. We describe our institutional experience utilizing an innovative single time-point paired scan protocol for comprehensive disease assessment and management. METHODS: We reviewed all patients over age 18 who underwent single time-point paired Thyrogen-stimulated FDG-PET and RAI scans for thyroid cancer staging or restaging at our institution between January 1, 2021 and December 31, 2024. RESULTS: 53 paired scans for 51 unique patients were included. 58.8% were female. Mean age was 61 years (range 19- 84). 80.3% of patients had papillary carcinoma, 5 had follicular carcinoma, 2 had Hurthle cell, and 2 had mixed histology. Most patients (29, 56.8%) had local disease, 21.6% had locoregional recurrence and 21.6% had distant metastasis. 34 patients had previously received RAI and 5 had received tyrosine-kinase inhibitor. Of 53 paired scans, 12 showed disease on both scans, 11 were negative on both scans, 20 showed FDG-avidity not seen on RAI scan, 9 showed RAI-avidity not seen on FDG-PET, and one showed mixed disease on both FDG-PET and RAI scans. DISCUSSION: The combination of FDG-PET and RAI scans offers several advantages, including prognostication as imaging biomarkers, enhanced detection of disease not visible on RAI scan alone due to biological heterogeneity of lesions, guidance for novel RAI resensitization strategies and RAI augmentation schemes. CONCLUSIONS: Single time-point paired FDG-PET and RAI scans offer critical and often complementary information to guide differentiated thyroid cancer management, especially in patients with locally advanced disease, distant metastases or RAI-refractory disease.
Artificial intelligence in medicineMinghao Mao, Yuxuan Qi, Jingya Zhang, Bin Zhang, Jiajun Wang
Joint PET/CT imaging combines functional and anatomical information, making multimodal tumor segmentation essential in clinical oncology. However, segmentation performance is often hindered by inter-modal feature entanglement and the lack of reliable uncertainty estimates. To tackle these issues, we propose an Anatomy-Consistent Segmentation Network (ACSN) based on feature disentanglement. In this network, the multimodal inputs are first processed with a dual-branch adversarial Feature Disentanglement Module (FDM) to extract the shared anatomical features of PET and CT. These features are then fed into a Feature Fusion Module (FFM) to extract tumor-specific representations via two Multi-receptive field Segmentation Backbones (MSB) (for CT and PET, respectively) and to extract fused features (from PET and CT) based on their uncertainties. In each MSB, a Feature Space Adjustment (FSA) module is developed to better align anatomical and tumor-related features. To better fuse multi-modal features and to mitigate the mis-calibration risk of traditional uncertainty calibration approaches, a Layer-wise Uncertainty Calibrator (LUC) is developed to progressively calibrate multi-scale features across the network, enabling finer-grained modeling of epistemic uncertainty and guiding more reliable multimodal fusion. The final tumor prediction is trustworthily produced by integrating calibrated evidence from PET, CT, and their fused representation under the guidance of Dempster-Shafer theory (DST). Experiments on the AutoPET and Hecktor datasets show that ACSN achieves competitive segmentation performance under the adopted 2D axial slice-wise evaluation protocol and provides calibrated uncertainty estimates that are associated with segmentation errors. These results suggest that ACSN may provide auxiliary information for uncertainty-aware PET/CT tumor segmentation and quality control. Our code will be available at https://github.com/narutodd/ACSN.
Clinical nuclear medicineGuang-Uei Hung, Lu-Hau Deng, Yueh-Tsung Lee
An 85-year-old woman with a history of left breast cancer underwent 18 F-FDG PET/CT for oncologic surveillance. Imaging demonstrated an incidental 7.5-cm intensely FDG-avid mass (SUVmax: 13.0) in the left lower abdominal wall, suspicious for metastatic disease. Incisional biopsy revealed fibrosis with multiple suture granulomas and foreign-body giant cell reaction, without malignancy. The patient had undergone transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction more than 10 years earlier, with subsequent ventral hernia mesh repairs. This case illustrates an important FDG-PET/CT pitfall of suture granuloma at remote reconstructive donor sites, which can mimic malignancy, persisting even decades after surgery.
Clinical nuclear medicineJuan Su, Haiyan Gao, Wei Zhang, Yan Deng
We report the 18 F-FDG PET/CT findings of IgG4-related autoimmune hepatitis mimicking hepatic malignancy in a 52-year-old man. The patient presented with intermittent fever, abdominal pain, and significantly elevated tumor markers. Initial evaluation with contrast-enhanced CT suggested hepatic malignancy. 18 F-FDG PET/CT demonstrated heterogeneous hepatic FDG uptake and multiregional hypermetabolic lymphadenopathy. Diagnosis was confirmed by cervical lymph node biopsy and a favorable clinical response to glucocorticoid therapy.
Clinical radiologyS Canham, S R Khan, M Naik, T D Barwick
Gynaecological malignancies are increasing in incidence in the UK, primarily driven by a rise in cases of endometrial cancer. The most common in order of prevalence thereafter are ovarian, cervical, vulval and vaginal cancers. Imaging is fundamental to their diagnosis, staging, response assessment and surveillance; and has significant implications in management by guiding local, regional or systemic treatment strategies. Advanced nuclear medicine imaging modalities, in particular [18F]-fluoro-2-deoxy-D-glucose (FDG) positron-emission tomography (PET)/computed tomography (CT), have an evolving role in combining anatomical and functional data, resulting in superior sensitivity and specificity for detection of sites of disease compared to conventional techniques. Sentinel node lymphoscintigraphy using [99mTc]-labelled nanocolloids is also integral to management pathways in selected cases, notably in patients with cervical and vulval cancer, to detect microscopic nodal disease and potentially avoid more extensive procedures which carry morbidity. This article provides a contemporary, evidence-based, overview of nuclear medicine imaging practice in gynaecological malignancy, separated by primary tumour location. It makes reference to current international guidelines and highlights key studies evidencing their utility, in addition to describing strengths and limitations compared to alternative modalities. Future advances on the horizon are also discussed, including novel radiopharmaceuticals and technological developments.
Clinical nuclear medicineAnthony Jeffrey, Christina Brown, Luke Coyle, Elizabeth Bernard
We report a case of marked biatrial 18 F-FDG uptake on PET/CT coinciding with the onset of symptomatic atrial flutter in a 77-year-old man with relapsed diffuse large B-cell lymphoma receiving ibrutinib. Serial imaging demonstrated normal atrial uptake before arrhythmia, marked uptake during atrial flutter, and complete normalisation following successful radiofrequency ablation. Atrial tachyarrhythmia represents an important and reversible cause of increased atrial FDG uptake and should prompt clinical and electrocardiographic correlation to avoid misinterpretation as cardiac disease involvement.
Primary extraskeletal Ewing sarcoma in the soft tissue of the neck is rare. A 29-year-old woman underwent 18F-FDG PET/CT and 68Ga-DOTATATE PET/CT for a mass in her neck. The patient complained of pain in the right side of the neck for 6 months. Both scans showed increased imaging agent uptake in the neck mass, which was subsequently diagnosed as extraskeletal Ewing sarcoma.
A 33-year-old woman presented with intermittent fever for 1 month, accompanied by pancytopenia and multiple enlarged lymph nodes in the bilateral neck, axillary and para-iliac regions on ultrasound. With informed consent, the patient was enrolled in a clinical trial comparing 18F-FDG and 68Ga-Pentixafor PET/CT for lymph node lesions. In contrast to the negative 18F-FDG PET/CT findings, 68Ga-Pentixafor PET/CT showed high tracer uptake in these lymph nodes. Subsequent cervical lymph node excision biopsy revealed reactive lymphoid hyperplasia; combined with elevated anti-ds-DNA, anti-SS-A, and anti-RNP titers, lupus lymphadenitis was diagnosed. After antisystemic lupus erythematosus therapy, the lymph nodes regressed significantly.
Clinical nuclear medicineChandra T R Singareddy, Annie K Baa, Shreyas R Kankara, Maria F Bukelo
Somatostatin receptor (SSTR) imaging is the preferred modality for staging well-differentiated neuroendocrine tumors (NETs) and detecting unknown primary NETs. If SSTR imaging is negative, 18F-FDG PET/CT may be done to rule out tumor heterogeneity. We report a case of a 36-year-old woman with a well-differentiated grade I NET, who initially presented with severe right hypochondriac pain and vomiting. Standard diagnostic workup with 68Ga-DOTANOC followed by 18F-FDG PET/CT was negative; however, 68Ga-FAPI-04 PET/CT demonstrated intense tracer-avid lesions in pancreatic primary and liver metastases.
Prostate-specific membrane antigen (PSMA) PET/CT has emerged as a sensitive and specific imaging modality for the detection and staging of prostate cancer that facilitates detection of locoregional recurrence as well as distant metastases more accurately compared with conventional imaging. Metastatic penile involvement from prostate adenocarcinoma is extremely uncommon and can be missed, highlighting the importance of careful image interpretation. Increasingly progressive PSMA uptake on follow-up is an important marker of disease progression. We present a case of 60-year-old man with carcinoma prostate after radical prostatectomy was subjected to follow-up. PSMA PET/CT imaging revealed penile metastasis. Therefore, PSMA PET/CT plays a critical role in maximal surveillance and therapeutic planning in prostate cancer.