Annals of Nuclear Medicine最新文献

{"title":"Glass versus resin microspheres in ⁹⁰Y radioembolization for hepatocellular carcinoma: toxicity patterns under uniform voxel-based dosimetry.","authors":"Ali Dablan, Enes Mustafa Kaya, Meryem Kaya, Emrah Birol, Çağrı Erdim, Mustafa Fatih Arslan, Mehmet Cingöz, Oğuzhan Türksayar, Cihan Şin, Halil Burak Kapucu, İpek Kerimel Öztürk, İlker Mahmut Kayaoğlu, Tevfik Güzelbey, Burcu Esen Akkaş","doi":"10.1007/s12149-026-02300-2","DOIUrl":"https://doi.org/10.1007/s12149-026-02300-2","url":null,"abstract":"<p><strong>Objectives: </strong>To compare safety outcomes and toxicity patterns of glass and resin microspheres in patients undergoing yttrium-90 (⁹⁰Y) transarterial radioembolization (TARE) for hepatocellular carcinoma (HCC), using uniform voxel-based dosimetry for both platforms and toxicity comparisons adjusted for treatment extent and tumor burden.</p><p><strong>Materials and methods: </strong>This retrospective single-center study included 103 consecutive patients with HCC and preserved liver function treated with ⁹⁰Y-TARE between June 2020 and June 2024 using glass-based (n = 70) or resin-based (n = 33) microspheres, selected according to routine practice and product availability. Absorbed doses for both cohorts were derived from voxel-based ⁹⁹ᵐTc-MAA SPECT/CT dosimetry. Adverse events (AEs) were graded with CTCAE version 5.0. The primary endpoint was overall AE incidence; secondary endpoints were specific toxicity patterns and dose-toxicity associations, examined with multivariable logistic regression adjusting for treatment extent and tumor volume. Progression-free survival (PFS) and overall survival (OS) were compared with the log-rank test.</p><p><strong>Results: </strong>Overall AE incidence did not differ between glass and resin microspheres (glass 37.1% vs. resin 30.3%; p = 0.497), and all AEs were grade 1-2. Tumor and non-tumorous liver absorbed doses were similar. Bilirubin toxicity was more frequent with glass microspheres (glass 28.6% vs. resin 9.1%; p = 0.027), whereas hemoglobin decline was more common with resin microspheres (glass 10.0% vs. resin 30.3%; p = 0.010); both exploratory differences persisted after adjustment for treatment extent and tumor volume. Lung shunt fraction, a baseline patient-level parameter, was higher with resin (glass 2.6% vs. resin 4.1%; p = 0.043). Higher lung absorbed dose was associated with AE occurrence overall, without a significant lung dose × microsphere-type interaction (p = 0.41). Neither PFS (median, glass 9 vs. resin 12 months; p = 0.868) nor OS (glass 23 vs. resin 29 months; p = 0.929) differed significantly.</p><p><strong>Conclusions: </strong>Glass and resin microspheres showed no significant difference in overall AE incidence-without formally establishing equivalence-but differed in their patterns of mild laboratory toxicity independently of treatment extent and tumor burden. These exploratory findings support careful, individualized dosimetric assessment and require confirmation in prospective multicenter studies, but do not provide criteria for microsphere selection.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164577","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":"Association of SUVmax and never-smoker/never- or minimally-drinker history with PD-L1 expression in resected oral squamous cell carcinoma: a nodal-status-stratified analysis.","authors":"Yuhua Hu, Ying Yuan, Ting Gu, Feng Xu","doi":"10.1007/s12149-026-02301-1","DOIUrl":"https://doi.org/10.1007/s12149-026-02301-1","url":null,"abstract":"<p><strong>Background: </strong>Programmed death-ligand 1 (PD-L1) is a critical biomarker for immunotherapy selection in oral squamous cell carcinoma (OSCC). However, the relationships between PD-L1 expression and non-invasive indicators, such as metabolic parameters derived from ¹⁸F-FDG PET/CT and never-smoker/never- or minimally-drinker (NSND) history, remain poorly defined. Moreover, whether these associations differ across nodal subgroups has not been investigated.</p><p><strong>Methods: </strong>This retrospective study included 147 patients with resected OSCC who underwent preoperative PET/CT. Factors associated with high PD-L1 expression (combined positive score [CPS] ≥ 20) were assessed using logistic regression in the overall cohort and with subgroup analyses stratified by nodal status and formal interaction testing.</p><p><strong>Results: </strong>In the overall cohort, maximum standardized uptake value (SUVmax) (odds ratio [OR] per unit increase = 1.067; 95% confidence interval [CI]: 1.013-1.123; P = 0.014) and gender (OR = 2.254; 95% CI: 1.029-4.936; P = 0.042) were independently associated with high PD-L1 expression. After stratification by nodal status, no clinicopathological or metabolic variable was significantly associated with PD-L1 expression in pN0 patients. In contrast, among pN+ patients, SUVmax (OR per unit increase = 1.113; 95% CI: 1.015-1.222; P = 0.024) and NSND (OR = 4.127; 95% CI: 1.362-12.501; P = 0.012) emerged as independent predictors. The NSND × pN interaction was significant (P = 0.004), whereas the SUVmax × pN interaction was not (P = 0.225).</p><p><strong>Conclusions: </strong>SUVmax may serve as a candidate non-invasive indicator, whereas the association between NSND and high PD-L1 expression was modified by nodal status, with a significant effect in node-positive patients. These findings are hypothesis-generating and require external validation.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164227","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":"Head-to-head comparison of ⁶⁸Ga-FAPI and ¹⁸F-FDG PET/CT in intracranial space-occupying lesions.","authors":"Raydel BrianKwee Amalo, Aih Cahyani, Hendra Budiawan, Budi Darmawan, Kharisma Perdani Kusumahstuti, Arifudin Achmad, Basuki Hidayat, Achmad Hussein Sundawa Kartamihardja","doi":"10.1007/s12149-026-02304-y","DOIUrl":"https://doi.org/10.1007/s12149-026-02304-y","url":null,"abstract":"<p><strong>Purpose: </strong>Intracranial space-occupying lesions (SOL), including primary brain tumors, metastases, and inflammatory lesions, require accurate characterization for diagnosis and management. Although ¹⁸F-FDG PET/CT reflects tumor glucose metabolism, its performance in the brain is limited by high physiological uptake. ⁶⁸Ga-FAPI PET/CT targets fibroblast activation protein in the tumor microenvironment and may provide complementary biological information with improved lesion conspicuity. This study aimed to compare ⁶⁸Ga-FAPI and ¹⁸F-FDG PET/CT for the evaluation of intracranial SOL.</p><p><strong>Methods: </strong>Thirty-five patients with 55 intracranial lesions underwent paired ⁶⁸Ga-FAPI and ¹⁸F-FDG PET/CT within a 7-day interval. Imaging findings were compared with histopathology (n = 9) and/or MRI (n = 46) as reference standards. Lesion detection rate, diagnostic performance, tumor-to-background ratio (TBR), and semi-quantitative uptake parameters normalized to lean body mass (SUL) were evaluated. Receiver operating characteristic (ROC) analyses were performed to assess the ability of each tracer to differentiate neoplastic from non-neoplastic lesions.</p><p><strong>Results: </strong>⁶⁸Ga-FAPI PET/CT detected more lesions than ¹⁸F-FDG PET/CT (48/55, 87.3% vs. 36/55, 65.5%) and approached the detection rate of MRI (54/55, 98.2%). FAPI demonstrated higher sensitivity and accuracy, whereas FDG showed higher specificity. FAPI demonstrated a significantly higher tumor-to-background ratio (TBR) than FDG (median, 342.00 [IQR, 164.25-502.00] vs. 4.71 [IQR, 3.48-7.42]; Z = 5.07, p < 0.001) in paired analysis of 34 lesions with measurable uptake on both tracers. In primary tumors, FAPI detected all lesions (13/13), whereas FDG detected 9/13 lesions. ROC analysis showed comparable diagnostic performance for differentiating neoplastic from non-neoplastic lesions (AUC 0.794 for FAPI vs. 0.796 for FDG). Exploratory analysis in high-grade tumors (n = 5) suggested a potential association between higher FDG uptake and shorter overall survival.</p><p><strong>Conclusion: </strong>In this cohort, intracranial lesions were predominantly metastatic, with MRI showing the highest detection rate. Compared with ¹⁸F-FDG PET/CT, ⁶⁸Ga-FAPI PET/CT demonstrated higher lesion detection and tumor-to-background contrast, approaching MRI performance. These findings support a complementary role for ⁶⁸Ga-FAPI PET/CT alongside MRI and ¹⁸F-FDG PET/CT in selected intracranial lesions, particularly when lesion conspicuity is limited by the high physiological brain uptake of FDG.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164733","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":"Predictive value of left ventricular ¹⁸F-FDG PET/CT derived parameters and uptake patterns for chemotherapy-induced cardiotoxicity in patients with lymphoma.","authors":"Mai Huy Thong, Mai Hong Son, Tran Ba Khoa, Jin Chun Paeng","doi":"10.1007/s12149-026-02299-6","DOIUrl":"https://doi.org/10.1007/s12149-026-02299-6","url":null,"abstract":"<p><strong>Background: </strong>Anthracycline-induced cardiotoxicity significantly impacts the survival and quality of life of lymphoma patients. Since traditional echocardiographic markers often detect injury only after irreversible damage, there is an urgent need for early biomarkers. We aimed to evaluate the predictive value of myocardial FDG uptake patterns and quantitative parameters from routine oncologic PET/CT for cancer therapy-related cardiac dysfunction (CTRCD).</p><p><strong>Methods: </strong>This retrospective cohort study included lymphoma patients treated with anthracycline-based regimens at a single hospital between 2015 and 2024. Patients underwent FDG PET/CT at baseline and after chemotherapy. CTRCD was operationally defined using the LVEF-based component of the 2022 ESC cardio-oncology guidelines on follow-up echocardiography. Metabolic parameters including maximal standard uptake value (SUVmax), cardiac metabolic volume (CMV), cardiac metabolic activity (CMA), and visual uptake patterns were analyzed on pre and post-treatment PET scans.</p><p><strong>Results: </strong>Post-treatment SUVmax, CMV, and CMA were significantly higher in patients who developed cardiotoxicity (p = 0.04, 0.017, and 0.03, respectively). In univariable logistic regression, focal/diffuse myocardial uptake was significantly associated with CTRCD, whereas SUVmax ≥8.49 and CMV ≥66.9 showed borderline associations. In multivariable analysis including SUVmax, CMV, and focal/diffuse uptake pattern, only the focal/diffuse uptake pattern remained independently associated with CTRCD (OR = 10.71, 95% CI: 2.10-54.69, p = 0.004). Notably, absent myocardial FDG uptake after treatment was observed only in patients without CTRCD in this cohort. Baseline PET parameters showed no significant predictive value (p = n.s.).</p><p><strong>Conclusion: </strong>Routine post-treatment oncologic FDG PET/CT may provide exploratory information on myocardial metabolic changes associated with CTRCD in lymphoma patients receiving anthracycline-based chemotherapy. Although quantitative PET parameters differed between patients with and without CTRCD, the focal/diffuse myocardial uptake pattern was the only imaging variable that remained independently associated with CTRCD after multivariable adjustment. These findings should be considered hypothesis-generating and require prospective validation using standardized myocardial metabolic preparation and predefined imaging timepoints.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149163934","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":"Inflammation and dosimetry in radioembolization: is C-reactive protein enough, or should we refine our biomarkers and dosimetric tools?","authors":"Luca Filippi, Murat Fani Bozkurt","doi":"10.1007/s12149-026-02303-z","DOIUrl":"https://doi.org/10.1007/s12149-026-02303-z","url":null,"abstract":"","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164020","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":"A cohort electron blood self-dose fraction and its propagated uncertainty for ¹²⁴I PET pre-therapy dosimetry in radioiodine therapy of differentiated thyroid cancer.","authors":"Mohamed Badawy, Lachlan McIntosh, Price Jackson, Ian Jong","doi":"10.1007/s12149-026-02297-8","DOIUrl":"https://doi.org/10.1007/s12149-026-02297-8","url":null,"abstract":"<p><strong>Objective: </strong>Pre-therapy blood-marrow dosimetry for ¹³¹I treatment of differentiated thyroid cancer (DTC) requires serial imaging and blood sampling, limiting clinical adoption. When blood data are unavailable, operators fall back to fixed or imaging-only prescribing, usually without an explicit uncertainty bound. We characterise the cohort electron blood self-dose fraction (β_frac) in a single-centre ¹²⁴I PET cohort and quantify the uncertainty incurred by substituting that reference for patient-specific blood data.</p><p><strong>Methods: </strong>Retrospective single-centre analysis of 18 pre-therapy ¹²⁴I PET courses in 15 DTC patients with paired serial venous blood-counting, all prepared by thyroid-hormone withdrawal. Time-activity curves were fitted in the ¹³¹I therapy frame following the EANM Standard Operational Procedure, separating D_blood into its electron (β, blood self-dose) and photon (γ, body cross-fire) components. The substitution uncertainty was propagated analytically, then validated against patient-level errors by leave-one-patient-out cross-validation.</p><p><strong>Results: </strong>The cohort β fraction was 84.3 ± 4.8% across 18 courses (mean ± SD; median 85.4%; 95% CI 82.0-86.7%), and 84.4 ± 4.6% over the 15 patients. The β fraction decreased with body weight (- 0.113 pp/kg, p = 0.019), although not significantly when reduced to one value per patient (p = 0.118); the association is therefore exploratory. Substitution gave a per-patient 1-σ uncertainty on the imaging-only D_blood estimate of ≈ 30%. Under leave-one-patient-out cross-validation the mean absolute percentage error was 26.3% and the RMSE 32.7%, with 12 of 18 courses within ± 30% of their reference.</p><p><strong>Conclusions: </strong>A cohort β fraction of 84.3 ± 4.8% is proposed as a fall-back reference for blood-free prescribing in DTC radioiodine therapy. Because the estimator's error is multiplicative on the estimate, a prescribing cap must come from the lower tail of that error, giving approximately 1.0-1.2 Gy in this cohort. No 95% coverage is demonstrated at this sample size, and the cap is offered as an exploratory observation requiring local confirmation rather than a validated threshold. The decomposition is imaging-modality agnostic for ¹³¹I clearance studies and therefore potentially applicable to low-dose ¹³¹I SPECT, although no SPECT data were analysed here.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164888","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":"PSMA-targeted radioligand therapy in prostate cancer: evidence hierarchy, platform maturity of ¹⁷⁷Lu-PSMA-617, and the clinical differentiation challenge for emerging radionuclides.","authors":"En Ting Lin","doi":"10.1007/s12149-026-02302-0","DOIUrl":"https://doi.org/10.1007/s12149-026-02302-0","url":null,"abstract":"<p><p>Among prostate-specific membrane antigen (PSMA)-directed radioligand therapies (RLT), ¹⁷⁷Lu-PSMA-617 is supported by two peer-reviewed phase III randomised controlled trials in metastatic castration-resistant prostate cancer (VISION and PSMAfore) and one in metastatic hormone-sensitive prostate cancer (PSMAddition). This structured narrative review uses eight predefined PubMed evidence sets, yielding 931 unique records after deduplication, to describe the study-design distribution and evidence-maturity profile of established and emerging PSMA-RLT strategies, including ¹⁷⁷Lu-PSMA-617, other Lu-177 PSMA agents, ²²⁵Ac, ¹⁶¹Tb, ²¹²Pb, ²¹¹At, and ⁹⁰Y. The review addresses five evidence questions: the differential patient-selection criteria between TheraP and VISION; rPFS-to-OS interpretation in PSMAfore; the sequencing implications of earlier hormone-sensitive RLT use; xerostomia and daughter-nuclide redistribution as unresolved development barriers for ²²⁵Ac-PSMA; and whether the microdosimetric rationale for ¹⁶¹Tb-PSMA is supported by clinical comparative data. The current evidence base identifies ¹⁷⁷Lu-PSMA-617 as the most mature PSMA-RLT platform, while emerging radionuclides remain dependent on prospective clinical differentiation.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149163995","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":"Prospective feasibility study of [68Ga]Gallium citrate PET/CT for treatment response assessment in spinal tuberculosis: exploratory comparison with follow-up [18 F]FDG PET/CT.","authors":"Justin K Varghese, Saumya Sara Sunny, Justin Arockiaraj, K Venkatesh, S Abi Manesh, S Mahasampath Gowri, Julie Hephzibah","doi":"10.1007/s12149-026-02296-9","DOIUrl":"https://doi.org/10.1007/s12149-026-02296-9","url":null,"abstract":"<p><strong>Objective: </strong>Spinal tuberculosis (STB) remains a major clinical challenge in high-burden countries. Infection imaging agents such as [18 F]FDG and [67Ga]Gallium citrate have limitations in specificity and interpretation. [68Ga]Gallium citrate, produced via a [68Ge/68Ga] generator, offers logistical and economic advantages. This prospective feasibility study evaluated the potential utility of [68Ga]Gallium citrate PET/CT in patients with spinal tuberculosis and descriptively explored follow-up [18 F]FDG PET/CT findings in a subset of patients.</p><p><strong>Methods: </strong>Thirty-two patients with suspected or confirmed spinal TB underwent early treatment baseline [68Ga]Gallium citrate PET/CT within one month of ATT initiation. Spinal lesions demonstrating [68Ga]Gallium citrate uptake equal to or greater than abdominal aortic blood-pool activity were visually classified as positive. Follow-up [68Ga]Gallium citrate PET/CT was performed after 9-12 months in 21 patients, all of whom demonstrated favourable clinical response. Seventeen of these patients also underwent follow-up [18 F]FDG PET/CT. Imaging findings were descriptively correlated with available clinical, radiological, biochemical, microbiological, and histopathological findings.</p><p><strong>Results: </strong>At early treatment baseline imaging, 22/32 patients (68.8%) demonstrated increased spinal [68Ga]Gallium citrate uptake, whereas 10/32 (31.2%) showed no abnormal spinal uptake. Among the 21 patients who underwent follow-up [68Ga]Gallium citrate PET/CT, 12 had demonstrated positive spinal uptake at baseline and 9 had been negative. All 12 baseline-positive patients demonstrated resolution of spinal [68Ga]Gallium citrate uptake at follow-up, while the 9 baseline-negative patients remained negative. All 21 patients demonstrated favourable clinical response. Among the 17 patients who also underwent follow-up [18 F]FDG PET/CT, residual spinal [18 F]FDG uptake was observed in 13, whereas 4 showed no abnormal uptake.</p><p><strong>Conclusion: </strong>In this prospective feasibility study, all patients with baseline [68Ga]Gallium citrate avidity who underwent follow-up imaging demonstrated complete resolution of tracer uptake, accompanied by a favourable clinical response. Because no treatment failures or non-responders were encountered, the ability of [68Ga]Gallium citrate PET/CT to identify persistent active disease or predict treatment outcome could not be assessed. However, persistent [18 F]FDG uptake was observed in several patients at follow-up. These findings should be interpreted as exploratory, given the absence of baseline [18 F]FDG PET/CT for comparison. Larger prospective studies including patients with heterogeneous treatment outcomes are required to determine the role of [68Ga]Gallium citrate PET/CT in treatment response assessment.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149103038","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":"Dose-activity relationship in [¹³¹I]NaI therapy for differentiated thyroid carcinoma.","authors":"Álvaro Luján-Expósito","doi":"10.1007/s12149-026-02290-1","DOIUrl":"https://doi.org/10.1007/s12149-026-02290-1","url":null,"abstract":"<p><strong>Objective: </strong>Current clinical practice guidelines often advocate for fixed [¹³¹I]NaI activity prescriptions based on patient diagnosis and risk stratification, frequently disregarding individual patient-specific radioiodine kinetics. This approach may result in substantial variability in the absorbed dose to target tissues and organs at risk. This study aimed to analyze the relationship between the absorbed dose in target organs (thyroid remnants) and organs at risk (red bone marrow) with potential explanatory variables, particularly the administered [¹³¹I]NaI activity in the treatment of differentiated thyroid carcinoma (DTC).</p><p><strong>Methods: </strong>A cross-sectional pilot study was conducted involving 50 DTC patients treated with [¹³¹I]NaI at the Hospital Clínico Universitario Virgen de la Arrixaca (HCUVA) in Murcia between September 2024 and May 2025. Baseline patient data and other treatment-specific data available in their clinical records were collected to calculate the absorbed dose according to the existing protocol for this purpose at the center.</p><p><strong>Results: </strong>No significant correlation was observed between the absorbed dose in thyroid remnants and the administered activity. Conversely, a significant association was found between the absorbed dose in the red bone marrow and the administered activity.</p><p><strong>Conclusions: </strong>Administering [¹³¹I]NaI without individualizing treatment based on radiopharmaceutical kinetics and patient-specific tumor burden does not result in proportionally higher absorbed doses in thyroid remnants or enhanced therapeutic efficacy. Instead, it significantly increases the absorbed dose to organs at risk.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149103014","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":"Reconstruction robustness of liver-referenced adaptive thresholding for ⁶⁸Ga-PSMA-11 PET/CT volumetry: a comparative analysis of systematic bias and individual-patient variability.","authors":"Ellen Schötz, Dominic Ufton, Jasmin Weindler, Matthias Schmidt, Katrin S Roth, Alexander Drzezga, Carsten Kobe","doi":"10.1007/s12149-026-02298-7","DOIUrl":"https://doi.org/10.1007/s12149-026-02298-7","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Objective: &lt;/strong&gt;PSMA tumor volume (PSMA-TV) is increasingly investigated as a quantitative biomarker for treatment assessment and prognostic stratification in metastatic castration-resistant prostate cancer (mCRPC). However, PSMA-TV depends on segmentation methodology and may be affected by reconstruction-related changes in PET image characteristics. This study evaluated the robustness of different PSMA-TV segmentation approaches across two reconstruction presets and investigated systematic bias, individual-patient disagreement, and equivalence between reconstruction settings.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Forty patients with mCRPC undergoing &lt;sup&gt;68&lt;/sup&gt;Ga-PSMA-11-PET/CT were retrospectively analyzed. PSMA-TV was quantified using three segmentation approaches: a fixed SUV threshold of 4.0 (T1), a liver-referenced adaptive threshold based on physiological liver uptake (T2), and a lesion-specific 41% SUV&lt;sub&gt;max&lt;/sub&gt; threshold (T3). Two reconstruction presets differing in image reconstruction parameters were compared. Systematic differences were assessed using signed differences, while individual disagreement was evaluated using absolute differences and median absolute percentage differences. Agreement was assessed using intraclass correlation coefficients (ICC) and logarithmic Bland-Altman analysis. Formal equivalence testing was performed using two one-sided tests (TOST) with exploratory margins of ± 10%, ± 20%, and ± 30% of mean PSMA-TV.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;PSMA-TV measurements demonstrated threshold-dependent reconstruction sensitivity. T3 showed the largest reconstruction-related variability, with a median signed relative difference of - 53.9% and markedly increased median absolute percentage difference (53.9%). In contrast, T1 and T2 showed substantially lower proportional disagreement (12.7% and 12.1%, respectively). T2 demonstrated the smallest systematic bias between reconstructions (median signed difference 0.4 mL; relative difference 1.1%) compared with T1 (16.9 mL; 9.0%). ICC values indicated high consistency for T1 (0.96; 95% CI, 0.93-0.98) and T2 (0.97; 95% CI, 0.94-0.98), whereas T3 showed lower precision (0.82; 95% CI, 0.29-0.93). Log-ratio Bland-Altman analysis demonstrated no evidence of proportional bias for any threshold. T2 was the only approach demonstrating equivalence within the strictest exploratory ± 10% margin.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;Reconstruction-dependent effects on PSMA-TV are strongly influenced by segmentation methodology. Liver-referenced adaptive thresholding minimized systematic reconstruction-related bias and demonstrated the highest robustness among evaluated approaches, although individual variability was not completely eliminated. Relative SUV&lt;sub&gt;max&lt;/sub&gt;-based segmentation showed substantially greater susceptibility to reconstruction changes. These findings support further evaluation of liver-referenced thresholding for standardized PSMA-TV assessment in longitu","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149103071","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}