Annals of Nuclear Medicine最新文献

{"title":"Development and validation of a nomogram for predicting bone marrow involvement in lymphoma patients based on ¹⁸F-FDG PET radiomics and clinical factors.","authors":"Denglu Lu, Xinyu Zhu, Xingyu Mu, Xiaoqi Huang, Feng Wei, Lilan Qin, Qixin Liu, Wei Fu, Yanyun Deng","doi":"10.1007/s12149-025-02041-8","DOIUrl":"10.1007/s12149-025-02041-8","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to develop and validate a nomogram combining ¹⁸F-FDG PET radiomics and clinical factors to non-invasively predict bone marrow involvement (BMI) in patients with lymphoma.</p><p><strong>Methods: </strong>A radiomics nomogram was developed using monocentric data, randomly divided into a training set (70%) and a test set (30%). Bone marrow biopsy (BMB) served as the gold standard for BMI diagnosis. Independent clinical risk factors were identified through univariate and multivariate logistic regression analyses to construct a clinical model. Radiomics features were extracted from PET and CT images and selected using least absolute shrinkage and selection operator (LASSO) regression, yielding a radiomics score (Rad_score) for each patient. Models based on clinical factors, CT Rad_score, and PET Rad_score were established and evaluated using eight machine learning algorithms to identify the optimal prediction model. A combined model was constructed and presented as a nomogram. Model performance was assessed using the area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis (DCA).</p><p><strong>Results: </strong>A total of 160 patients were included, of whom 70 had BMI based on BMB results. The training group comprised 112 patients (BMI: 56, without BMI: 56), while the test group included 48 patients (BMI: 14, without BMI: 34). Independent risk factors, including the number of extranodal involvements and B symptoms, were incorporated into the clinical model. In the clinical model, CT Rad_score, and PET Rad_score, the AUCs in the test set were 0.820 (95% CI: 0.705-0.935), 0.538 (95% CI: 0.351-0.723), and 0.836 (95% CI: 0.686-0.986). Due to the limited diagnostic performance of CT Rad_score, the nomogram was constructed using PET Rad_score and the clinical model. The radiomics nomogram achieved AUCs of 0.916 (95% CI: 0.865-0.967) in the training set and 0.863 (95% CI: 0.763-0.964) in the test set. Calibration curves and DCA confirmed the nomogram's discrimination, calibration, and clinical utility in both sets.</p><p><strong>Conclusion: </strong>By integrating PET Rad_score, the number of extranodal involvements, and B symptoms, this ¹⁸F-FDG PET radiomics-based nomogram offers a non-invasive method to predict bone marrow status in lymphoma patients, providing nuclear medicine physicians with valuable decision support for pre-treatment evaluation.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"663-675"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143741896","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":"Metabolic tumor parameters on ¹⁸F-FDG PET/CT can predict the expression of PD-L1 and prognosis in patients with fumarate hydratase-deficient renal cell carcinoma.","authors":"Shuhui Huang, Yaowen Zhang, Wei Zhang, Tian Tian, Hongyuan Dai, Mengfang Qi, Minggang Su, Hao Zeng, Rui Huang","doi":"10.1007/s12149-025-02039-2","DOIUrl":"10.1007/s12149-025-02039-2","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to comprehensively evaluate the performance of fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) and investigate the association between metabolic parameters, programmed cell death ligand 1 (PD-L1) expression, and prognosis in patients with fumarate hydratase-deficient renal cell carcinoma (FHRCC).</p><p><strong>Methods: </strong>Twenty-nine patients with FHRCC were prospectively enrolled from May 2020 to February 2023 for ¹⁸F-FDG PET/CT. The maximum standardized uptake value (SUVmax), peak standardized uptake value (SUVpeak), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of primary/recurrent tumors were analyzed. The relationship between PET metabolic parameters, clinicopathological features and prognosis were evaluated.</p><p><strong>Results: </strong>Primary/recurrent and metastatic lesions showed FDG avidity, without metabolic differences between them. In our analysis, SUVmax of whole body (WB-SUVmax), SUVpeak of whole body (WB-SUVpeak), MTV of whole body (WB-MTV), and TLG of whole body (WB-TLG) were associated with the expression of PD-L1. The optimal cut-off values of WB-SUVmax, WB-SUVpeak, WB-MTV, and WB-TLG for predicting positive PD-L1 expression were 9.86 (AUC 0.814), 6.92 (AUC 0.848), 19.61 cm³ (AUC 0.803), and 58.39 g (AUC 0.841), respectively. Survival analysis further demonstrated that patients with WB-SUVpeak ≥ 8.92 had shorter time to progression than those with WB-SUVpeak < 8.92 (11.0 mo vs. 21.0 mo, P = 0.047).</p><p><strong>Conclusions: </strong>¹⁸F-FDG PET/CT is effective in detecting FHRCC lesions due to their hypermetabolic nature. PET metabolic parameters can serve as predictors of positive PD-L1 expression, with higher values observed in FHRCC patients with positive PD-L1 expression. Additionally, WB-SUVpeak is a significant predictor of prognosis in patients with FHRCC.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"641-649"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143633425","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":"Low-iodine diet: what to eat and avoid before iodine-131 procedures?","authors":"Gabriela O Silva, Fernando G Romeiro, Sonia Marta Moriguchi, Gláucia Maria F S Mazeto, Katia H Koga","doi":"10.1007/s12149-025-02043-6","DOIUrl":"10.1007/s12149-025-02043-6","url":null,"abstract":"<p><strong>Objective: </strong>The aim of this study was to compile a list of low-iodine foods for use in the Low-Iodine Diet (LID) to optimize the uptake of Iodine-131 by cells, which is used in the diagnosis and treatment of thyroid gland disorders.</p><p><strong>Methods: </strong>A bibliographic research was conducted focusing on the most commonly consumed foods in Brazil. Iodine quantification was derived from both national and international food composition tables, with an emphasis on sources indicating the highest concentrations of this microelement. The foods were organized into categories, and their iodine levels were presented in micrograms per 100 grams of food.</p><p><strong>Results: </strong>The compiled list includes foods classified into categories such as cereals, legumes, vegetables, fruits, flours, oils, fats, meats, dairy products, and beverages. Foods with more than 50 μg of iodine per 100 g were identified and classified separately. Based on the findings, marine-derived foods should be avoided, while dairy products and eggs can be consumed, provided substitutions are made.</p><p><strong>Conclusion: </strong>Identifying and quantifying low-iodine foods is essential for guiding the LID, making it more effective and better suited to the population's needs. Legumes, vegetables, and most fruits can be consumed in larger quantities, forming the core of the diet.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"687-695"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143959468","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":"Pre-treatment ¹¹¹In-pentetreotide SPECT/CT vs. baseline ¹⁷⁷Lu-DOTATATE SPECT/CT: are there differences in lesion uptake and detectability?","authors":"Masatoshi Hotta, Daisuke Horikawa, Keiichi Kurihara, Shuhei Ohashi, Kaori Saito, Fuyuki Inagaki","doi":"10.1007/s12149-025-02050-7","DOIUrl":"10.1007/s12149-025-02050-7","url":null,"abstract":"<p><strong>Background: </strong>¹¹¹In-pentetreotide imaging remains used for pre-treatment screening in peptide receptor radionuclide therapy (PRRT) in regions where somatostatin receptor (SSTR)-PET tracers are clinically unavailable. Post-treatment ¹⁷⁷Lu-DOTATATE imaging at the first PRRT cycle serves as a baseline for response assessment on subsequent post-treatment imaging, paralleling the role of pre-treatment ¹¹¹In-pentetreotide imaging. However, differences between these SSTR scans have not been reported. This study aims to compare ¹¹¹In-pentetreotide and ¹⁷⁷Lu-DOTATATE imaging, focusing on lesion uptake and numbers.</p><p><strong>Methods: </strong>This retrospective, single-center study included patients with neuroendocrine tumors (NETs) who underwent PRRT at our hospital. Planar and SPECT/CT of pre-treatment ¹¹¹In-pentetreotide and post-treatment ¹⁷⁷Lu-DOTATATE imaging at the first PRRT cycle were analyzed. For visual analysis, the number of SSTR-positive (Krenning score ≥ 2) lesions was counted for each tracer. For quantitative analysis, up to three representative SSTR-positive lesions per patient were selected, and the maximum standardized uptake value (SUVmax) and tumor-to-background (T/B) ratio were measured. Wilcoxon signed-rank test was used to compare lesion counts and uptake parameters.</p><p><strong>Results: </strong>A total of 10 patients and 28 lesions were included. The median interval between ¹¹¹In-pentetreotide and ¹⁷⁷Lu-DOTATATE imaging was 43 days. ¹⁷⁷Lu-DOTATATE imaging detected significantly more lesions than ¹¹¹In-pentetreotide on both planar (median 10 vs. 6.5 lesions, p = 0.009) and SPECT/CT (median 13.5 vs. 8 lesions, p = 0.014). Lesion uptake was higher with ¹⁷⁷Lu-DOTATATE, with SUVmax (median 4.5 vs. 2.9, p < 0.001) and T/B ratios (median 13.9 vs. 4.7, p < 0.001). Sub-centimeter lesions accounted for most of the additional detections on ¹⁷⁷Lu-DOTATATE SPECT/CT.</p><p><strong>Conclusion: </strong>Baseline ¹⁷⁷Lu-DOTATATE imaging demonstrated higher lesion uptake and detected more lesions compared to pre-treatment ¹¹¹In-pentetreotide imaging. Careful interpretation of baseline ¹⁷⁷Lu-DOTATATE imaging is essential to avoid misinterpreting the increased number of detected lesions as disease progression. Screening with ¹¹¹In-pentetreotide imaging may underestimate treatable lesions by PRRT, particularly when planar imaging alone is used, highlighting the need for SSTR PET in pre-treatment evaluation.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"747-753"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143956989","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":"Physiological bio-distribution of ⁶⁸Ga-DOTA-TATE in pediatric patients.","authors":"Nuh Filizoglu, Salih Ozguven, Selin Kesim, Kevser Oksuzoglu, Feyza Caglıyan, Tunc Ones, Fuat Dede, Halil Turgut Turoglu, Tanju Yusuf Erdil","doi":"10.1007/s12149-025-02040-9","DOIUrl":"10.1007/s12149-025-02040-9","url":null,"abstract":"<p><strong>Objective: </strong>Somatostatin receptors (SSTRs) are G protein-coupled transmembrane receptors that serve as a specific molecular target for a number of radiopharmaceuticals utilized for the imaging of neuroendocrine tumors (NETs). ⁶⁸Ga-DOTA-TATE is a somatostatin analog that demonstrates a high affinity for SSTR2. Pediatric malignancies, such as neuroblastoma, pheochromocytoma, and paraganglioma, have been shown to express SSTR2, and ⁶⁸Ga-DOTA-TATE is currently being used to evaluate these pediatric neoplasms. We aimed to analyze the distribution pattern of ⁶⁸Ga-DOTA-TATE based on age and location in pediatric patients.</p><p><strong>Methods: </strong>We retrospectively analyzed 247 consecutive ⁶⁸Ga-DOTA-TATE whole-body PET/CT scans performed in our department from May 2015 to April 2024 in pediatric patients with known or suspected neuroblastoma, neuroendocrine malignancy, pheochromocytoma, and paraganglioma. 93 subjects were included in this study who were disease-free at the time of imaging and had no tracer-avid lesion on ⁶⁸Ga-DOTA-TATE PET/CT. The patients were divided into four groups according to age: infant (0-2 years), pre-school (3-6 years), school (7-12 years), and adolescent (13-18 years). A comparison of the SUV values of each organ across age groups was performed.</p><p><strong>Results: </strong>The highest levels of physiological uptake were observed in the spleen across all age groups, except for infants, who demonstrated the highest SUV values in the kidneys. ⁶⁸Ga-DOTA-TATE uptake in the parotid glands, submandibular glands, thyroid gland, thymus, liver, spleen, adrenal glands, stomach, intestines, uterus, prostate, and testes demonstrated a statistically significant increase in the adolescent age group. In contrast to all internal organs, the lowest SUV max values were observed for all growth plates within the adolescent age group.</p><p><strong>Conclusion: </strong>This study presents the bio-distribution pattern of ⁶⁸Ga-DOTA-TATE in pediatric patients, according to age and location. The ranges of the SUVmax and SUVmean values of ⁶⁸Ga-DOTA-TATE obtained in the various organs are of paramount importance for accurately diagnosing malignancy in ⁶⁸Ga-DOTA-TATE PET/CT studies.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"650-662"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12174203/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143662121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative voxel-based dosimetry with pre-treatment Tc-99m SPECT/CT and post-treatment Y-90 PET/MRI for radioembolization with Y-90 microspheres.","authors":"Burak Demir, Nuriye Ozlem Kucuk, Cigdem Soydal, Emre Can Celebioglu, Gizem Inal, Ecenur Dursun, Mehmet Sadık Bilgic, Digdem Kuru Oz, Atilla Halil Elhan, Kemal Metin Kir","doi":"10.1007/s12149-025-02052-5","DOIUrl":"10.1007/s12149-025-02052-5","url":null,"abstract":"<p><strong>Purpose: </strong>The aim of this study was to investigate the differences between voxel-based dosimetry and the mean absorbed doses calculated with pre-treatment Tc-99 m-MAA SPECT/CT and post-treatment Y-90 PET/MR images. We also sought to present a detailed comparison of dose-volume histograms (DVHs) calculated from pre- and post-treatment imaging.</p><p><strong>Methods: </strong>A total of 47 treatments and 41 patients were included in the analysis as six of the treatments were retreatments of the six patients. Multicompartment and voxel-based dosimetry were performed with pre-treatment Tc-99m-MAA SPECT/CT and Y-90 PET/MRI. Correlation coefficients between the two imaging methods for the mean absorbed dose of tumor, whole liver normal tissue, perfused normal tissue, T/N ratio and tumor D10, D50 and D90 values were calculated. Additionally, differences between these values were also evaluated with Bland-Altman plots.</p><p><strong>Results: </strong>Pre-treatment Tc-99m-MAA SPECT/CT accurately predicted the dose values for healthy liver parenchyma calculated with Y-90 PET/MRI but showed lower accuracy in predicting T/N ratio and tumor doses. There were significant variations in tumor-absorbed doses for both glass and resin microspheres. Additionally, D90 values were higher when calculated with SPECT/CT than with PET/MRI, whereas D10 values were higher in PET/MRI compared to SPECT/CT.</p><p><strong>Conclusion: </strong>The findings in our study suggest that Tc-99m-MAA SPECT/CT had higher accuracy in predicting the dose to the healthy liver parenchyma compared to the tumor, maintaining its importance in treatment planning.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"716-731"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12174238/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143954709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elapsed time changes of the brain radiopharmaceutical accumulation of the amyloid PET examination using ¹⁸F-flutemetamol.","authors":"Shota Takemoto, Koji Onuki, Keiko Tanimoto, Masaho Taniguchi, Takako Suero, Mio Okamoto, Satoshi Kimura, Monami Osawa, Haruka Takeshige-Amano, Noriko Nishikawa, Shigeki Aoki, Ryohei Kuwatsuru, Nobutaka Hattori, Koji Murakami","doi":"10.1007/s12149-025-02046-3","DOIUrl":"10.1007/s12149-025-02046-3","url":null,"abstract":"<p><strong>Objective: </strong>The purpose of this study was to examine how the radiopharmaceutical accumulation in the brain changes with the elapsed time between the administration of ¹⁸F-flutemetamol and the start of imaging, and to determine its effect on quantitative indices.</p><p><strong>Methods: </strong>The study population consisted of 25 subjects who agreed to participate in the study. After visual evaluation by the radiologist, 14 subjects tested negative for Aβ accumulation, and 11 subjects tested positive as well. The study population was treated with ¹⁸F-flutemeamol, and list mode acquisition was performed for 50 min starting at 60 min after the time of administration. From the acquired list data, five PET images were extracted at 10-min intervals from the start to the end of acquisition, a PET image corresponding to 20 min of acquisition from 60 min after administration, and a PET image corresponding to 20 min of acquisition from 90 min after administration, respectively. Pixel values were measured for the PET images created and quantitative indices (pixel value, SUVr, Centiloid scale) were calculated and compared.</p><p><strong>Results: </strong>In most of the PET images, pixel values showed a decreasing trend with elapsed time after radiopharmaceutical administration. Accordingly, calculated SUVr and Centiloid Scale also changed.</p><p><strong>Conclusions: </strong>Elapsed time after radiopharmaceutical administration resulted in a washout of the radiopharmaceutical accumulation in the brain. From this, it was suggested that the quantitative indices change.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"732-746"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12174224/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143956966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Factors and predictors affecting late external dose rates and isolation period in patients after lutetium-177-labeled DOTA-Tyr3-octreotate treatment for neuroendocrine tumors.","authors":"Naoto Wakabayashi, Shiro Watanabe, Satoshi Takeuchi, Takahiro Tsuchikawa, Yamato Munakata, Kenji Hirata, Rina Kimura, Junki Takenaka, Hiroshi Ishii, Kohsuke Kudo","doi":"10.1007/s12149-025-02044-5","DOIUrl":"10.1007/s12149-025-02044-5","url":null,"abstract":"<p><strong>Objective: </strong>In peptide receptor radionuclide therapy (PRRT) using lutetium-177-labeled DOTA-Tyr3-octreotate ([¹⁷⁷Lu] DOTATATE), isolation is required until the external dose rate at 1 m (EDR-1 m) from the body surface falls below the regulatory standards of each country. While it is known that renal function influences EDR-1 m reduction within 180 min post-administration, the factors affecting EDR-1 m on the day following administration (Late EDR-1 m) remain unclear. This study aimed to identify factors influencing Late EDR-1 m after PRRT using [¹⁷⁷Lu] DOTATATE for neuroendocrine tumors and to predict Late EDR-1 m using pretreatment [¹¹¹In] pentetreotide single-photon emission computed tomography/computed tomography (SPECT/CT) data.</p><p><strong>Methods: </strong>This study analyzed 111 PRRT cycles administered to 36 patients between September 2021 and August 2024. Late EDR-1 m was set as the dependent variable, whereas total radiopharmaceutical uptake (LUTtotal), dose per body weight, creatinine clearance (CCr), and albumin-bilirubin (ALBI) score were set as the independent variables in the multiple regression analysis. LUTtotal was calculated using SPECT/CT data acquired after the patient left the radiation therapy room, defining the volume of interest (VOI) as the area with SUVmean + 2SD or higher in the skeletal muscle. The VOI volume multiplied by the SUVmean was used to define LUTtotal. In addition, using [¹¹¹In] pentetreotide SPECT/CT data, the total radiopharmaceutical uptake (OCTtotal) was calculated in a manner similar to LUTtotal, and its correlation with LUTtotal was examined. A predictive equation for Late EDR-1 m was developed using the results of the multivariate analysis, and its performance was tested using subsequent cases between August 2024 and January 2025.</p><p><strong>Results: </strong>The median measured Late EDR-1 m was 8.0 (range, 4.0-26.0) μSv/h. LUTtotal and dose per body weight were significantly correlated with Late EDR-1 m, whereas CCr and ALBI scores were not. Based on the results of the multivariate analysis, the predictive equation using the dose per body weight, assuming a dosage of 7400 MBq and OCTtotal, achieved a root mean square error (RMSE) of 2.24 μSv/h. In subsequent test cases, the RMSE was 3.47 μSv/h.</p><p><strong>Conclusions: </strong>Late EDR-1 m is significantly correlated with LUTtotal and dose per body weight. It can be accurately predicted using [¹¹¹In] pentetreotide SPECT/CT data.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"696-706"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12174230/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143787560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Blood and bone marrow dosimetry for thyroid cancer patients prepared with rhTSH injection.","authors":"Amna Juma Al Jabri, Jennie Cooke, Seán Cournane, Marie-Louise Healy","doi":"10.1007/s12149-025-02042-7","DOIUrl":"10.1007/s12149-025-02042-7","url":null,"abstract":"<p><strong>Purpose: </strong>Radioiodine (¹³¹I) dosimetry is used to maximise tumour dose while reducing the chances of toxicity. High thyroid-stimulating-hormone (TSH) levels are required for ¹³¹I treatment, achieved through hormone withdrawal or intramuscular injection of recombinant human TSH (rhTSH). Both approaches have shown equivalent results, with the rhTSH approach reported to reduce morbidity and avoid hypothyroidism. There are established differences in ¹³¹I biokinetics using each method. This clinical cohort study investigated if pretherapy iodine biokinetics as measured using a dosimetry protocol without a dose of rhTSH are predictive of post therapy biokinetics in patients prepared with rhTSH injection.</p><p><strong>Methods: </strong>Thirteen patients with differentiated thyroid cancer (DTC) were recruited. An adaptation of the European Association of Nuclear Medicine (EANM) dosimetry protocol was conducted at St James's Hospital, Ireland. The maximum tolerable activity (MTA) was calculated using the EANM, Association of Physics in Medicine (AIFM) and Traino models, after administering ¹³¹I, and subsequent whole-body (WB) dose-rate measurements and blood-sampling were carried out. The MTA estimated from pre-therapeutic (PT) ¹³¹I tracer administration (6.07 ± 2.46 MBq) was compared to during therapy (DT) administration (3.88 ± 0.16 GBq).</p><p><strong>Results: </strong>The PT WB residence-time overestimated the DT with a difference of - 7.72 ± 8.13% (p = 0.007), while no significant difference is reported between the blood residence-time (1.13 ± 6.49%, p = 0.559). The EANM model reported the lowest difference of 1.73 ± 4.83% (p = 0.241) in MTA.</p><p><strong>Conclusion: </strong>This study validated the feasibility of using dosimetry in euthyroid patients to predict therapeutic ¹³¹I biokinetics in DTC patients prepared with rhTSH.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"676-686"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12174295/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143787508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the best time-point for 18F-FDG PET/CT delayed imaging in patients of small colorectal cancer liver metastasis with hypothyroidism based on diagnostic efficacy and image standardized uptake values.","authors":"Yusong Pei, Yanan Tong, Zhiguo Wang, Xinxin Qiao, Yanqing Liu, Guoxu Zhang","doi":"10.1007/s12149-025-02045-4","DOIUrl":"10.1007/s12149-025-02045-4","url":null,"abstract":"<p><strong>Objective: </strong>This study analyzes the role of positron emission tomography/computed tomography (PET/CT) in the diagnosis of small (< 10 mm) colorectal cancer liver metastasis (CRLM) lesions in patients with hypothyroidism. In particular, the impact of the best time for delayed imaging on improving diagnostic efficacy.</p><p><strong>Methods: </strong>We retrospectively analyzed 231 patients with small CRLM lesions with hypothyroidism who underwent dual time-point 18F-FDG PET/CT imaging. Based on the previous studies and clinical practice experience, 120-190 min was selected as the time range for delayed imaging, divided into eight teams in 10-min groups. The delayed images of the eight time periods were first analyzed and compared for diagnostic efficacy, and second analyzed and compared for standardized uptake value (SUV) and of PET/CT images to observe the trend of SUV values over time.</p><p><strong>Results: </strong>The results of diagnostic efficacy analysis indicated that the 180-min delay group had the highest diagnostic efficacy (sensitivity, specificity, and accuracy). Comparison of the SUV values with the delay time analysis showed that maximum standardized uptake value (SUVmax) increased with the delay time, and the normal liver tissue (SUVmean) decreased with the delay time, which resulted in the gradual increase in the ratio of the lesion to the normal liver tissue (TNR). By selecting the time-point with the highest TNR ratio and stable SUV value, and combining the results of diagnostic efficacy, this study successfully verified the best imaging time-point. After comprehensive consideration, 180 min was determined as the best imaging time-point, when the TNR reached the highest, the SUV value was stable, and the diagnostic efficacy was best.</p><p><strong>Conclusions: </strong>In this study, the impact of delayed imaging on the diagnostic efficacy and SUV value of PET/CT images in patients of small CRLM with hypothyroidism was shown intuitively, and the changing pattern of SUV at different time points was also observed. The best time-point for PET/CT delayed imaging was determined to be 180 min, which provides a new scanning program for the diagnosis in patients of small CRLM with hypothyroidism.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":"707-715"},"PeriodicalIF":2.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143762541","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}