Hellenic journal of nuclear medicine最新文献

{"title":"Characterization of regional brain metabolic changes in metastatic melanoma using ¹⁸F-FDG PET/CT imaging: A case report.","authors":"Om H Gandhi, Jaskeerat Gujral, Amir A Amanullah, Shiv Patil, Robert C Subtirelu, Eric M Teichner, Sedra A A Mhana, Thomas J Werner, Abass Alavi, Mona E Revheim","doi":"10.1967/s002449912944","DOIUrl":"10.1967/s002449912944","url":null,"abstract":"<p><p>Brain metastases occur in 40%-60% of melanoma patients and represent a major clinical challenge with historically poor prognosis. While conventional neuroimaging modalities such as magnetic resonance imaging (MRI) delineate metastases with high specificity, they cannot capture the widespread cerebral metabolic disruptions that underlie neurological impairment associated with infiltrative lesions. This case report demonstrates the utility of fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography-computed tomography (PET/CT) in characterizing regional brain metabolic changes in metastatic melanoma. We present a case of a 78-year-old female diagnosed with metastatic melanoma who underwent ¹⁸F-FDG PET/CT restaging. The imaging findings revealed hypometabolism in regions adjacent to hypoattenuation in the left occipital area, which was subsequently confirmed as a discrete parietal lobe metastasis on MRI. Quantitative assessment using MIMneuro software across 84 brain regions revealed diffuse metabolic disturbances extending beyond the focal lesion. The most pronounced hypometabolism was observed in the cingulate gyri (z=-4.47), cerebellum (z=-2.29), pons (z=-2.22), and temporal regions (z=-2.18). In contrast, marked hypermetabolism was noted in occipital and parietal regions (z=5.71). These widespread patterns support the concept that brain metastases can result in systemic neurological defects, disrupting mechanisms related to diaschisis, vascular regulation, and immune-mediated pathways. These findings highlight the utility of ¹⁸F-FDG PET/CT in uncovering functional brain alterations not visible on conventional imaging, offering potential value in clinical decision making and disease assessment of melanoma patients with brain metastases.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"34-38"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular imaging of dural microcalcification: Detection of active mineralization with ¹⁸F-NaF PET/CT.","authors":"Shiv Patil, Daniel Gharavi, Nirmal Patel, Robert Subtirelu, Om H Gandhi, Jaskeerat Gujral, Thomas J Werner, Poul F Høilund-Carlsen, Abass Alavi","doi":"10.1967/s002449912948","DOIUrl":"10.1967/s002449912948","url":null,"abstract":"<p><p>Dural calcification is frequently observed on computed tomography (CT) as an age-associated finding, yet its biological activity and potential for pathological progression remain poorly characterized. Fluorine-18-sodium fluoride (¹⁸F-NaF) is a positron emission tomography (PET) radiotracer that can detect biologically active microcalcification and may thus enable monitoring of such lesions. We describe a 73-year-old woman with hypertension, hypercholesterolemia, and atrial fibrillation who was incidentally found to have focal ¹⁸F-NaF uptake in the falx cerebri (mean standardized uptake value (SUVmean) 1.29, SUVmax 2.02) and tentorium cerebelli (SUVmean 1.08, SUVmax 1.76). This case highlights the novel capability of ¹⁸F-NaF PET to characterize dural mineralization at the molecular level and serve as a biomarker of lesion progression.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"50-51"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning models for predicting microvascular invasion in hepatocellular carcinoma with three-dimensional whole-lesion ¹⁸F-FDG PET radiomics.","authors":"Hong Yang, Dinghua Pang, Shilai Zhang, Zhi Yang, Meishe Gan, Linlin Wei, Ning Li, Hongjiao Wei, Guoyou Xiao, Hai Liao","doi":"10.1967/s002449912942","DOIUrl":"10.1967/s002449912942","url":null,"abstract":"<p><strong>Objective: </strong>To estimate the performance of machine learning models based on preoperative three-dimensional whole-lesion radiomics features for predicting microvascular invasion (MVI) in hepatocellular carcinoma (HCC).</p><p><strong>Subjects and methods: </strong>This retrospective study included 106 individuals who underwent preoperative fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) and were pathologically diagnosed with HCC at Guangxi Medical University Cancer Hospital between January 2018 and December 2023. Individuals were randomly assigned to training (n=74) and validation (n=32) sets. A total of 2,016 radiomic features were extracted from three-dimensional whole-lesion PET images. Least absolute shrinkage and selection operator regression combined with recursive feature elimination identified the optimal feature subset. Logistic regression (LR), Light Gradient Boosting Machine (LightGBM), and multilayer perceptron (MLP) models were developed. Model performance in the validation set was evaluated using precision, area under the receiver operating characteristic curve (AUC), and F1-score.</p><p><strong>Results: </strong>Six key radiomic features were selected. In the validation set, the LR model achieved an AUC of 0.703, precision of 0.750, and F1-score of 0.765; the LightGBM model achieved an AUC of 0.654, precision of 0.688, and F1-score of 0.687; and the MLP model achieved an AUC of 0.629, precision of 0.625, and F1-score of 0.625.</p><p><strong>Conclusion: </strong>The LR model demonstrates the best overall performance and shows promise for noninvasive preoperative MVI assessment.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"16-25"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Giant primary hepatic osteosarcoma: A rare case report and review of the literature.","authors":"Haoliang Zhu, Hangzhe Sun, Tianyun Zhang, Yu Chen, Siqi Wang","doi":"10.1967/s002449912946","DOIUrl":"10.1967/s002449912946","url":null,"abstract":"<p><strong>Objective: </strong>Primary hepatic extraskeletal osteosarcoma (PHOS) is an extremely rare and aggressive malignant tumor originating in the liver with no primary skeletal lesion. Less than 1% of all extraskeletal osteosarcomas occur in the liver, often presenting as a large abdominal mass with poor prognosis.</p><p><strong>Case presentation: </strong>We report a rare case of a 64-year-old man diagnosed with a giant PHOS (163×128×160mm) accompanied by pulmonary and lymph node metastases. Multimodal imaging magnetic resonance imaging (MRI), computed tomography (CT), bone scintigraphy, positron emission tomography (PET)/CT demonstrated a heterogeneous hepatic mass with extensive calcifications, rim enhancement, restricted diffusion, and elevated fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) uptake. Histopathological analysis confirmed the diagnosis, showing atypical mesenchymal cells producing osteoid matrix with strong special AT-rich sequence-binding protein 2 (SATB2) positivity and negative epithelial markers.</p><p><strong>Discussion: </strong>Imaging characteristics and immunohistochemical profiling were crucial in differentiating PHOS from hepatocellular carcinoma and metastatic osteosarcoma. The case supports the metaplasia theory of PHOS pathogenesis and highlights its radiologic-pathologic correlation, especially the \"cloud-like\" enhancement on imaging corresponding to unmineralized osteoid and vascular proliferation.</p><p><strong>Conclusion: </strong>This case highlights the diagnostic challenge and clinical significance of PHOS. Comprehensive imaging and pathological evaluation are essential for accurate diagnosis. Due to its rarity and aggressiveness, PHOS requires individualized management strategies, typically involving surgery and adjuvant therapies despite limited evidence-based guidelines.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"42-47"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Double myocardial bridge causing acute myocardial infarction in a premenopausal woman.","authors":"Varvara Valotassiou, Vasilios Dimopoulos, George Angelidis, Emmanouil Panagiotidis, Dimitrios Psimadas, John Skoularigis, Panagiotis Georgoulias","doi":"10.1967/s002449912945","DOIUrl":"10.1967/s002449912945","url":null,"abstract":"<p><p>Myocardial bridging is a congenital abnormality which is characterized by an intramuscular course of a segment of the coronary artery. The presence of myocardial bridging influences coronary vasculature due to mechanical compression and systolic milking. The symptoms and complications of myocardial bridging depend on the number and depth of the tunneled artery segments, the grade of systolic narrowing and the heart rate, and include myocardial ischemia, coronary spasm or acute coronary syndrome. Dual myocardial bridges are rare. We present a case of an acute myocardial infarction in a premenopausal woman due to double myocardial bridging which was identified on coronary angiography. Myocardial perfusion single photon emission tomography (SPECT) was performed for the evaluation of infarct size and residual ischemia.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"39-41"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comment on the impact of reconstruction algorithms on Deauville scoring in digital PET/CT.","authors":"Jiayi Chen","doi":"10.1967/s002449912951","DOIUrl":"10.1967/s002449912951","url":null,"abstract":"","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"58"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical value of early-phase ^99mTc-MIBI SPECT in rapid washout parathyroid adenomas.","authors":"Yiğithan Okar, Ceren Uğurlu","doi":"10.1967/s002449912943","DOIUrl":"10.1967/s002449912943","url":null,"abstract":"<p><strong>Objective: </strong>Parathyroid adenomas with rapid tracer washout may be missed on delayed-phase technetium-99m-sestamibi (^99mTc-MIBI) imaging, potentially leading to false-negative localization. This retrospective single-center study evaluated the clinical value of early-phase single photon emission computed tomography (SPECT) compared with delayed-phase SPECT in detecting rapid washout parathyroid adenomas, particularly in centers without access to SPECT/computed tomography (CT), and assessed whether this washout pattern could be predicted by biochemical parameters.</p><p><strong>Subjects and methods: </strong>Eighteen patients with surgically and histopathologically confirmed parathyroid adenomas who underwent dual-phase ^99mTc-MIBI SPECT imaging were included. Early-phase and delayed-phase SPECT images were independently reviewed by two experienced nuclear medicine physicians. Lesion detection rates were compared using McNemar's test, interobserver agreement was assessed using Cohen's kappa coefficient, and preoperative biochemical parameters were compared between adenomas detected only on early-phase imaging and those visible on delayed-phase imaging.</p><p><strong>Results: </strong>Early-phase SPECT enabled detection of all surgically confirmed adenomas, whereas delayed-phase SPECT failed to identify 8 of 18 lesions (44%) due to rapid tracer washout, with a statistically significant difference between the two phases (P<0.01). No significant differences were observed in preoperative biochemical parameters between rapid washout and persistent uptake groups, indicating that early washout could not be reliably predicted clinically. Despite localization being achieved using SPECT without CT correlation, postoperative parathyroid hormone levels normalized in all patients, confirming surgical success. Interobserver agreement was excellent for both imaging phases (κ=1.00).</p><p><strong>Conclusion: </strong>These findings indicate that early-phase ^99mTc-MIBI SPECT significantly improves detection of rapid washout parathyroid adenomas and, as this pattern cannot be anticipated biochemically, its routine inclusion represents a simple and cost-effective strategy with direct relevance for routine clinical practice in centers without SPECT/CT.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"26-33"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An auxiliary ¹⁸F-FDG uptake pattern clarifying equivocal adrenal gland mass after dual-tracer imaging with ¹²³I-mIBG SPECT/CT and ¹⁸F-FDG PET/CT.","authors":"Emil Novruzov, Sandra Jaschinski, Irene Esposito, Gerald Antoch, Alexandra Ljimani, Eduards Mamlins, Frederik L Giesel","doi":"10.1967/s002449912949","DOIUrl":"10.1967/s002449912949","url":null,"abstract":"<p><p>Pheochromocytomas are rare catecholamine-producing neuroendocrine tumors arising from the adrenal medulla. Several studies have reported activation of brown adipose tissue (BAT) in up to 30% of patients with pheochromocytoma. Brown adipose tissue is characterized by abundant mitochondria to provide heat generation rather than energy storage. Pheochromocytoma seems to act on BAT via two parallel mechanisms. These include the trans-differentiation of white to brown adipocyte as well as the hypertrophy of existing brown adipocytes and increased glucose uptake by noradrenergic (β-AR) sympathetic nervous system stimulation.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"52-53"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiple metastatic small cell carcinoma with extensive tumor thrombosis in the inferior mesenteric vein on ¹⁸F-FDG PET/CT.","authors":"Junjun Cheng, Xiaohong Ou","doi":"10.1967/s002449912947","DOIUrl":"10.1967/s002449912947","url":null,"abstract":"<p><p>The presence of intravascular tumor thrombus alters the staging, prognosis, and treatment paradigms of cancer patients. It most commonly complicates renal cell carcinoma, adrenocortical carcinoma, and hepatocellular carcinoma. Small cell carcinoma is a highly aggressive malignant neoplasm; however, venous tumor thrombus associated with small cell carcinoma is extremely rare. Herein, we report the fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) findings in an 87-year-old woman presenting with diffuse metastatic small cell carcinoma and superior mesenteric vein tumor thrombosis.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"48-49"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative bone SPECT/CT useful for selecting medical or surgery treatment in heterotopic ossification.","authors":"Kazuhiro Kitajima, Takayuki Kawaguchi, Toshiya Tachibana, Rika Yoshida, Yukihisa Tamaki, Masakatsu Tsurusaki, Koichiro Yamakado","doi":"10.1967/s002449912941","DOIUrl":"10.1967/s002449912941","url":null,"abstract":"<p><strong>Objective: </strong>Mature lamellar bone formation in extra-skeletal soft tissue is termed heterotopic ossification (HO). Surgical resection of HO is performed to preserve joint mobility, though timing is very important, as resection prior to HO maturation very often results in incomplete or inadequate excision, leading to recurrence. The present study was conducted to evaluate whether standardized uptake values (SUV) derived from quantitative bone single-photon emission computed tomography/computed tomography (SPECT/CT) are useful for assessing HO maturity and determining the appropriate timing of surgical resection.</p><p><strong>Subjects and methods: </strong>Eleven quantitative bone SPECT/CT scans from six patients with HO were analyzed.</p><p><strong>Results: </strong>Four of the patients with a total of 10 lesions received medical treatment (bisphosphonates), and their mean SUVmax, SUVpeak, SUVmean, metabolic bone volume (MBV), and total bone uptake (TBU) values were 13.12±12.39 (range 4.41-44.35), 11.81±11.27 (4.12-40.53), 7.64±7.16 (3.02-26.05), 81.83±111.02 (15.68-290.64), and 781.30±1,301.78 (61.87-3,301.87), respectively. The two patients who underwent surgery had a total of two lesions and those mean values in those cases were 3.21±1.67 (2.03, 4.39), 2.99±1.65 (1.82, 4.15), 2.22±1.27 (1.32, 3.11), 6.77±2.21 (5.2, 8.33), and 16.39±13.46 (6.87, 25.9), respectively. Two who were evaluated with use of serial bone SPECT/CT scanning for assessment of medical treatment response showed a gradual decrease in SUV, reflecting the effectiveness of bisphosphonate therapy (SUVmax 9.01-8.94-6.11-5.37 and 6.93-5.93-4.41, respectively).</p><p><strong>Conclusion: </strong>Standardized uptake value derived from quantitative bone SPECT/CT scanning is useful for monitoring HO metabolic activity and determining the appropriate timing of surgical resection.</p>","PeriodicalId":12871,"journal":{"name":"Hellenic journal of nuclear medicine","volume":" ","pages":"10-15"},"PeriodicalIF":1.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147722720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}