Annals of Nuclear Medicine最新文献

{"title":"Response to the comment on “[11C]-Methionine PET/CT in evaluation of bone marrow infiltration and usage as a prognostic tool in multiple myeloma”","authors":"Elgin Ozkan, Burak Demir, Guldane Cengiz Seval, Mine Araz, Cigdem Soydal, Irem Mesci, Gulcin Miyase Sonmez, Meral Beksac, Nuriye Ozlem Kucuk","doi":"10.1007/s12149-026-02237-6","DOIUrl":"10.1007/s12149-026-02237-6","url":null,"abstract":"","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 9","pages":"1148 - 1149"},"PeriodicalIF":2.4,"publicationDate":"2026-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148012976","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":"Correction: Biochemical failure after radical prostatectomy with PSA ≤ 1 ng/mL: prediction of PSMA-positive metastatic disease","authors":"Giulia Santo, Helena Rosarno, Antonino Restuccia, Giuseppe Lucio Cascini, Francesco Grillone, Francesco Cicone","doi":"10.1007/s12149-026-02238-5","DOIUrl":"10.1007/s12149-026-02238-5","url":null,"abstract":"","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 7","pages":"844 - 844"},"PeriodicalIF":2.4,"publicationDate":"2026-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12149-026-02238-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148012892","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":"Is It time to move beyond FDG toward a more specific yet broadly applicable radiotracer such as FAPI? why yes—and why not","authors":"Mahdi Zirakchian Zadeh","doi":"10.1007/s12149-026-02228-7","DOIUrl":"10.1007/s12149-026-02228-7","url":null,"abstract":"<div><p>Fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT remains the most widely used oncologic imaging modality due to its ability to exploit increased glucose metabolism, a fundamental hallmark shared by many malignancies. However, FDG is limited by its lack of specificity, including uptake in inflammatory and benign processes, high physiologic background activity in the brain, required patient preparation such as fasting—which can be challenging in diabetic patients—and relatively long uptake times, as well as the absence of inherent theranostic potential. These limitations have fueled ongoing debate regarding whether it is time to replace FDG with a more specific yet broadly applicable radiotracer, such as fibroblast activation protein inhibitor (FAPI), which has gained substantial attention across multiple research and clinical scenarios. FAPI PET offers low background uptake, relatively rapid imaging protocols, and theranostic potential. Nevertheless, FDG is unlikely to be replaced in the near future, as it reflects a fundamental metabolic feature shared by many cancers, benefits from well-established infrastructure and reader familiarity, offers robust quantitative capabilities, and remains cost-effective. Rather than replacement, FDG and FAPI are be better regarded as complementary, biology-driven imaging tools, particularly given their fundamentally different mechanisms for detecting cancer.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 9","pages":"1031 - 1042"},"PeriodicalIF":2.4,"publicationDate":"2026-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148012897","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":"Baseline PSMA-ligand PET/CT as a predictive biomarker for early progression in metastatic castration-resistant prostate cancer patients undergoing [177Lu]Lu-PSMA-617 radioligand therapy","authors":"Baptiste Mercier,&nbsp;Léane Dréano,&nbsp;Estelle Neveu,&nbsp;Florian Estrade,&nbsp;Romain Mathieu,&nbsp;Brigitte Laguerre,&nbsp;Laurence Crouzet,&nbsp;Antonin Broyelle,&nbsp;Christelle Bouvry,&nbsp;Florence Le Jeune,&nbsp;Julie Faudemer,&nbsp;Julien Farce,&nbsp;Xavier Palard-Novello","doi":"10.1007/s12149-026-02236-7","DOIUrl":"10.1007/s12149-026-02236-7","url":null,"abstract":"<div><h3>Objective</h3><p>To identify predictive biomarkers of early progression in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with [¹⁷⁷Lu]Lu-PSMA-617 radioligand therapy (RLT).</p><h3>Methods</h3><p>This retrospective single-center study included all consecutive mCRPC patients who initiated [¹⁷⁷Lu]Lu-PSMA-617 RLT outside of clinical trials between July 2022 and May 2025, receiving at least 2 injections, and had a minimum follow-up period of 6 months. Early progression was defined as treatment discontinuation due to progression before the third injection or biochemical progression based on Prostate Cancer Working Group 3 without treatment discontinuation. Baseline clinical data, biological data, PSMA-ligand PET/CT and [¹⁸F]FDG PET/CT parameters were collected. Univariate and multivariate logistic regression were used to identify factors associated with early progression.</p><h3>Results</h3><p>A total of 87 patients were included. Early progression was observed in 27 (31%) of patients. Among baseline data, only a prior second-line chemotherapy with cabazitaxel and PSMA-ligand SUVmean &lt; 6.0 were significantly and independently associated with early progression (respectively adjusted OR = 3.2; 95% CI: 1.02–10.6; <i>p</i> = 0.049 and adjusted OR = 12.6 ; 95% CI: 3.7–50.9; <i>p</i> &lt; 0.001). PSMA-ligand SUVmean &lt; 6.0 was also significantly and independently associated with a poorer overall survival (median overall survival = 11 months (95% CI: 5–24) vs. 22 months (95% CI: 15 – not reach) for patients with PSMA-ligand SUVmean ≥ 6.0; <i>p</i> = 0.019).</p><h3>Conclusions</h3><p>PSMA-ligand SUVmean is an independent predictor of early progression confirming that baseline PSMA-ligand PET/CT may serve for risk stratification in mCRPC treated with [¹⁷⁷Lu]Lu-PSMA-617 RLT.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 10","pages":"1210 - 1218"},"PeriodicalIF":2.4,"publicationDate":"2026-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148004238","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":"Early clinical experience with ⁶⁸Ga-Trivehexin PET/CT in parathyroid adenomas: a proof-of- concept imaging study","authors":"Mehmet Erdogan,&nbsp;Hakan Korkmaz,&nbsp;Mustafa Avcı,&nbsp;Zeynep Özdemir,&nbsp;Ahmet Tunç,&nbsp;Sevim Süreyya Sengul","doi":"10.1007/s12149-026-02232-x","DOIUrl":"10.1007/s12149-026-02232-x","url":null,"abstract":"<div><h3>Objective</h3><p>The success of surgical treatment in Primary Hyperparathyroidism (PHPT) depends on the accurate localization of the parathyroid adenoma. Although cervical ultrasonography (USI) and ⁹⁹ᵐTc- Sestamibi scintigraphy are common methods in this context, their diagnostic performance might be limited in small, ectopically located, or biologically atypical lesions. As a novel PET agent targeting integrin αvβ6 (alpha-v beta-6), ⁶⁸Ga-Trivehexin can image biological processes associated with pathological tissue remodeling. This proof-of-concept study aimed to evaluate the feasibility and potential diagnostic contribution of ⁶⁸Ga-Trivehexin PET/CT in detecting parathyroid adenoma in patients with PHPT.</p><h3>Methods</h3><p>This single-center, prospective proof-of-concept study included 28 patients who had a biochemical diagnosis of PHPT. All patients underwent neck ultrasound, ⁹⁹ᵐTc-Sestamibi parathyroid scintigraphy, and ⁶⁸Ga-Trivehexin PET/CT imaging. Fine Needle Aspiration Biopsy (FNAB) and Parathyroid Hormone (PTH) washout tests were performed for some patients as clinically necessary. Histopathological findings were used as the reference standard in patients who underwent surgery. The agreement between imaging methods was evaluated with Cohen’s Kappa coefficient for exploratory purposes.</p><h3>Results</h3><p>A total of 64.2% of the patients were female, and the mean age was 56.1 ± 11.3 years. ⁹⁹ᵐTc- Sestamibi scintigraphy was found to be positive in 60.7% of the patients, while the positivity rate for ⁶⁸Ga-Trivehexin PET/CT was 78.6%. A significant proportion of cases with negative ⁹⁹ᵐTc- Sestamibi scintigraphy showed positive lesions with ⁶⁸Ga-Trivehexin PET/CT. Statistically significant, moderate agreement levels were detected in all patients between ⁹⁹ᵐTc-Sestamibi scintigraphy and ⁶⁸Ga-Trivehexin PET/CT (kappa = 0.430; p = 0.013). A moderate level of agreement was observed between the two methods in patients with histopathologically confirmed parathyroid adenoma (kappa = 0.429; p = 0.070).</p><h3>Conclusion</h3><p>The results of this proof-of-concept study imply that ⁶⁸Ga-Trivehexin PET/CT may be a feasible and promising imaging method for localizing parathyroid adenomas in patients with primary hyperparathyroidism. It may offer potential contributions as a complementary diagnostic tool,</p><p>particularly in selected cases where conventional imaging methods are limited. Further large, multicenter studies are needed to confirm these findings.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 9","pages":"1131 - 1137"},"PeriodicalIF":2.4,"publicationDate":"2026-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12149-026-02232-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147986148","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":"18 F-FDG PET/CT Derived Volumetric Parameters Can Predict Outcome in Pediatric Ewing Sarcoma","authors":"Başak Soydaş-Turan,&nbsp;Bilge Volkan-Salancı,&nbsp;Burça Aydın,&nbsp;Pınar Kiratli","doi":"10.1007/s12149-026-02229-6","DOIUrl":"10.1007/s12149-026-02229-6","url":null,"abstract":"<div><h3>Objective</h3><p>To evaluate the prognostic and predictive value of metabolic and volumetric parameters obtained from baseline (PET1) and post-chemotherapy (PET2) 18 F-FDG PET/CT in pediatric Ewing sarcoma (EWS) patients, focusing on their associations with histopathologic response, metastatic presentation, overall survival (OS), and progression-free survival (PFS).</p><h3>Methods</h3><p>This retrospective single tertiary academic center study included 55 pediatric EWS patients who underwent PET1. Twenty-four patients also had PET2. SUVmax, SUVpeak, metabolic tumor volume (MTV), total lesion glycolysis (TLG) and their percentage changes (∆) between PET scans were calculated using absolute (SUV 2.0 and 2.5) and relative (40% and 45%) thresholds. Anatomic tumor volume was also measured. Histopathologic evaluation was available for 40 patients with PET1 and 18 patients with PET2. Associations were analyzed using logistic and Cox regression models.</p><h3>Results</h3><p>Baseline metabolic and volumetric PET parameters were significantly higher in patients with presenting metastasis. Among these, TLG (45%) was identified as the only independent predictor of metastatic presentation (OR = 1.026, <i>p</i> = 0.019). Baseline MTV (2.0) was independently associated with shorter OS (HR = 1.026, <i>p</i> = 0.003) and PFS (HR = 1.035, <i>p</i> = 0.038). Combined stratification using MTV (2.0) and histologic response revealed that patients with an unfavorable histologic response but low MTV demonstrated superior OS and PFS rates than those with an unfavorable response and high MTV. The survival outcomes of patients with a favorable histologic response and high MTV were comparable to those with an unfavorable response and low MTV. However, PET parameters did not reliably predict histopathologic response in this cohort.</p><h3>Conclusions</h3><p>Baseline MTV (2.0) demonstrated prognostic value for OS and PFS, while TLG (45%) independently predicted metastatic presentation in pediatric EWS. The combination of MTV (2.0) and histologic response appears to provide complementary prognostic information. Prospective, multicenter studies with standardized imaging and treatment protocols are warranted to validate the role of volumetric 18 F-FDG PET parameters in clinical risk stratification.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 9","pages":"1121 - 1130"},"PeriodicalIF":2.4,"publicationDate":"2026-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12149-026-02229-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147980168","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":"Baseline FDG PET/CT SUVmax predicts POD24 and progression-free survival in newly diagnosed follicular lymphoma","authors":"Yu-Chieh Lin,&nbsp;Chin-Chuan Chang,&nbsp;Tsung-Jang Yeh,&nbsp;Tzu-Yu Hsieh,&nbsp;Min-Hong Wang,&nbsp;Jeng-Shiun Du,&nbsp;Yuh-Ching Gau,&nbsp;Ching-I Yang,&nbsp;Ching-Ping Lee,&nbsp;Wen-Hsin Chang,&nbsp;Chin-Mu Hsu,&nbsp;Hui-Ching Wang,&nbsp;Hui-Hua Hsiao,&nbsp;Yi-Chang Liu,&nbsp;Shih-Feng Cho","doi":"10.1007/s12149-026-02230-z","DOIUrl":"10.1007/s12149-026-02230-z","url":null,"abstract":"<div><h3>Objective</h3><p>Progression of disease within 24 months (POD24) identifies high-risk follicular lymphoma (FL) patients with poor outcomes. The prognostic role of baseline 18 F-FDG PET/CT maximum standardized uptake value (SUVmax) in follicular lymphoma (FL) remains uncertain, especially in Asian populations. We examined the association between baseline SUVmax and POD24, as well as its prognostic relevance for progression-free survival (PFS) in newly diagnosed FL patients.</p><h3>Methods</h3><p>We retrospectively analyzed 119 newly diagnosed FL patients who underwent baseline 18 F-FDG PET/CT at a single institution between 2012 and 2024. Whole-body SUVmax (the highest SUVmax across all lesions) and site-specific SUVmax values were recorded. Clinical variables, including baseline laboratory parameters and histologic grade, were collected. Receiver operating characteristic (ROC) analysis was used to explore an optimal SUVmax cutoff for POD24. Associations with POD24 and PFS were evaluated using Kaplan-Meier analysis and Cox proportional hazards models.</p><h3>Results</h3><p>The median PFS was 54.3 months, and 24.4% of patients experienced POD24. Higher baseline SUVmax was associated with shorter PFS across evaluated sites. ROC analysis showed modest ability to distinguish patients with POD24, with an optimal whole-body SUVmax cutoff of 14.5. Patients with SUVmax &gt; 14.5 had significantly inferior PFS compared with those with SUVmax ≤ 14.5 (median PFS 38.2 months vs. not reached; log-rank <i>p</i> = 0.024) and a higher incidence of POD24 (44.4% vs. 20.8%). In Cox regression, SUVmax as a continuous variable was associated with PFS (HR 1.065, 95% CI 1.008–1.125, <i>p</i> = 0.025), and SUVmax &gt; 14.5 remained an independent predictor of inferior PFS after multivariable adjustment (HR 2.645, 95% CI 1.082–6.467, <i>p</i> = 0.033).</p><h3>Conclusions</h3><p>Baseline whole-body SUVmax is an independent predictor of PFS. A ROC-derived cutoff of 14.5 identified patients with inferior PFS and was associated with a higher incidence of POD24 in newly diagnosed FL. Given its simplicity and availability, SUVmax may serve as a practical adjunctive metabolic biomarker to support baseline risk assessment in routine clinical practice.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 9","pages":"1098 - 1110"},"PeriodicalIF":2.4,"publicationDate":"2026-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147969499","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":"Integration of ⁶⁸Ga-DOTA-TOC PET/CT into radiotherapy planning for intracranial meningiomas: A precision-imaging approach to tumor delineation","authors":"Sharjeel Usmani,&nbsp;Syed Furqan Hashmi,&nbsp;Anjali Jain,&nbsp;Said Al Saifi,&nbsp;Asiya alBusaidi,&nbsp;Khulood Al Riyami","doi":"10.1007/s12149-026-02226-9","DOIUrl":"10.1007/s12149-026-02226-9","url":null,"abstract":"<div><h3>Background</h3><p>Accurate target delineation is critical for radiotherapy (RT) planning in intracranial meningiomas, particularly in complex anatomical regions such as the skull base or in postoperative settings. Meningiomas characteristically overexpress somatostatin receptor subtype-2 (SSTR2), allowing high-contrast molecular imaging with ⁶⁸Ga-DOTA-TOC PET/CT. This study evaluated the impact of integrating SSTR-PET with conventional imaging on RT target delineation in patients with intracranial meningiomas.</p><h3>Methods</h3><p>In this single-center observational study, 25 consecutive patients with intracranial meningioma undergoing radiotherapy planning underwent MRI and ⁶⁸Ga-DOTA-TOC PET/CT. Gross tumor volumes were delineated using MRI alone and PET-fused CT images. PET-derived biological tumor volume (BTV) was generated using a 40% SUVmax threshold. Semiquantitative PET parameters, SUVmax and tumor-to-background ratio (TBR), were recorded. Changes in GTV delineation following PET integration were analyzed.</p><h3>Results</h3><p>⁶⁸Ga-DOTA-TOC PET demonstrated intense SSTR expression (SUVmax 14.19 ± 10.88; TBRmax 83.48 ± 76.18) and precisely delineated tumor margins. PET identified osseous involvement in 40% of patients compared with 16% detected on MRI alone and revealed additional nonadjacent disease sites in 28% of cases. PET-based GTVs were significantly smaller than MRI-based volumes (12.01 ± 12.77 cm³ vs. 20.02 ± 18.71 cm³, <i>p</i> = 0.012). Integration of PET resulted in clinically relevant contour modification (&gt; 5%) in 17 of 20 evaluable patients, including bone-specific adjustments in 12.</p><h3>Conclusion</h3><p>⁶⁸Ga-DOTA-TOC PET/CT demonstrated complementary value in radiotherapy planning for intracranial meningiomas, producing systematic geometric modifications in target volumes, with more frequent osseous involvement detection compared to MRI alone. These hypothesis-generating findings require validation in larger prospective multicenter studies with long-term clinical outcome endpoints before routine clinical adoption.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 9","pages":"1089 - 1097"},"PeriodicalIF":2.4,"publicationDate":"2026-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147969563","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":"Semiquantitative SSTR PET metrics show molecular–morphologic discordance after 177Lu-DOTATATE in gastroenteropancreatic neuroendocrine neoplasms: an exploratory paired target-lesion analysis","authors":"Agostino Chiaravalloti,&nbsp;Martina Egidi,&nbsp;Antonio D’Agostini,&nbsp;Luca Filippi,&nbsp;Elizabeth Katherine Anna Triumbari,&nbsp;Oreste Bagni,&nbsp;Orazio Schillaci","doi":"10.1007/s12149-026-02231-y","DOIUrl":"10.1007/s12149-026-02231-y","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Objective&lt;/h3&gt;&lt;p&gt;To assess whether simple paired semiquantitative somatostatin receptor (SSTR) PET metrics identify treatment-related changes after 177Lu-DOTATATE in patients with gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) and to explore their relationship with single-lesion size measured on contrast-enhanced CT in an exploratory paired target-lesion framework.&lt;/p&gt;&lt;h3&gt;Methods&lt;/h3&gt;&lt;p&gt;We retrospectively evaluated 29 consecutive patients with GEP-NENs who completed four cycles of 177Lu-DOTATATE and underwent baseline and post-treatment 68Ga-DOTA-peptide PET/CT. Median age at treatment initiation was 64.5 years, 18/29 patients were male, 15 had a pancreatic primary, 13 an intestinal primary, and 1 a pancreatic/duodenal primary of uncertain origin. Most tumors were grade 2 (17/29), and liver metastases were present in 26/29 patients. For each patient, semiquantitative measurements were extracted from the target lesion recorded in the institutional database at baseline and post-treatment assessment. SUVmax, SUVmean, target lesion size, Krenning score, tumor-to-liver ratio, and tumor-to-blood ratio were compared between baseline and post-treatment imaging. Exploratory molecular response was defined as a reduction of at least 30% in semiquantitative PET parameters, whereas exploratory morphologic change was defined as a reduction of at least 20% in lesion size measured on contrast-enhanced CT. Baseline PET/CT was typically performed within 4–6 weeks before PRRT initiation, and post-treatment PET/CT approximately 3 months after PRRT completion according to institutional routine practice.&lt;/p&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;p&gt;Median target lesion SUVmax decreased from 52.22 to 29.73 (&lt;i&gt;p&lt;/i&gt; = 0.0007), and median SUVmean decreased from 11.44 to 7.25 (&lt;i&gt;p&lt;/i&gt; = 0.023). Median target lesion size changed from 2.80 to 2.49 cm and was not significantly different (&lt;i&gt;p&lt;/i&gt; = 0.168). Tumor-to-liver ratio decreased from 9.38 to 5.31 (&lt;i&gt;p&lt;/i&gt; &lt; 0.001), and tumor-to-blood ratio from 45.96 to 22.57 (&lt;i&gt;p&lt;/i&gt; &lt; 0.001). Krenning score showed a modest but significant shift despite an unchanged median value of 4 (&lt;i&gt;p&lt;/i&gt; = 0.0049). Using predefined exploratory thresholds, molecular response based on tumor-to-blood ratio was observed in 20/29 patients, whereas exploratory contrast-enhanced CT-based size reduction was observed in 9/29; 14 of 20 patients with molecular response showed no concomitant size reduction. Among 24 patients with evaluable final imaging response, a tumor-to-blood ratio reduction of at least 30% was observed in 10/11 patients with complete or partial response and in 7/13 with stable or progressive disease.&lt;/p&gt;&lt;h3&gt;Conclusions&lt;/h3&gt;&lt;p&gt;In this exploratory paired target-lesion analysis, semiquantitative SSTR PET metrics showed significant treatment-related changes after 177Lu-DOTATATE, whereas paired single-lesion size changes on contrast-enhanced CT were modest. These findings support the presence of molecular–morphologic discordance a","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 9","pages":"1111 - 1120"},"PeriodicalIF":2.4,"publicationDate":"2026-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12149-026-02231-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147961761","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":"Whole-brain histogram analysis and top 20% gray and white matter ratio of amyloid positron emission tomography: A comparison with the centiloid scale","authors":"Ryo Yamakuni,&nbsp;Shinya Seino,&nbsp;Anna Yamaki,&nbsp;Atsushi Shima,&nbsp;Hironobu Ishikawa,&nbsp;Mitsunari Abe,&nbsp;Harumasa Takano,&nbsp;Nobukatsu Sawamoto,&nbsp;Hirofumi Sekino,&nbsp;Shiro Ishii,&nbsp;Kenji Fukushima,&nbsp;Naoyuki Ukon,&nbsp;Takashi Kasai,&nbsp;Jin Narumoto,&nbsp;Takashi Hanakawa,&nbsp;Hiroshi Ito,&nbsp;Parkinson’s, Alzheimer’s disease Dimensional Neuroimaging Initiative (PADNI)","doi":"10.1007/s12149-026-02218-9","DOIUrl":"10.1007/s12149-026-02218-9","url":null,"abstract":"<div><h3>Objective</h3><p>To compare whole-brain histogram analysis (WBHA) of amyloid-β (Aβ) positron emission tomography (PET) using several magnetic resonance imaging (MRI)-based brain extraction (brain extraction tool [BET]) methods, to evaluate a novel quantitative analysis method, namely the Top 20% Gray and White Matter Ratio (GW-ratio), to determine appropriate thresholds, and to evaluate diagnostic performance in comparison with the Centiloid scale (CL).</p><h3>Methods</h3><p>We analyzed structural MRI, ¹⁸F-flutemetamol amyloid PET images, and dementia severity scores (Global Clinical Dementia Rating [G-CDR] and Mini-Mental State Examination [MMSE]) of 262 participants. For WBHA, BET was performed using structural MRI and three different BET software programs, namely High-Definition-BET (HD-BET), FMRIB Software Library (FSL), and Statistical Parametric Mapping (SPM). Skewness and mode-to-mean ratio (MMR) were measured using brain-extracted PET. The Top 20% Map was generated from SPM BET images, separated into gray and white matter voxels, and their ratio was calculated as the GW-ratio. The CL value was computed using structural MRI. Aβ-negativity or positivity was visually determined.</p><h3>Results</h3><p>Skewness from three BET methods was strongly negatively correlated with CL. Skewness (HD-BET) showed the strongest correlation (R = -0.9043). Moreover, the GW-ratio strongly correlated with CL (R = 0.8332), whereas MMR, particularly MMR (FSL) (R = 0.2112), showed poor correlation. All indicators significantly distinguished Aβ-negative from Aβ-positive visuals. CL had the highest area under the curve (AUC, 0.9959), followed by skewness (HD-BET) (0.9927), Top 20% GW-ratio (0.9872), and skewness (SPM) (0.9779), with no statistical difference between CL and skewness (HD-BET) (<i>P</i> = 0.5763). Based on mean and SD values from 118 cognitively unimpaired (G-CDR = 0, MMSE ≥ 28) and visually Aβ-negative participants, 95% cut-off limits for Aβ-negative individuals without dementia symptoms were: CL ≤ 12.9, skewness (HD-BET) ≥ 0.1769, MMR (HD-BET) ≤ 0.9372, skewness (FSL) ≥ 0.1819, MMR (FSL) ≤ 1.9132, skewness (SPM) ≥ -0.0382, MMR (SPM) ≤ 1.1274, and GW-ratio ≤ 0.1079.</p><h3>Conclusion</h3><p>WBHA using MRI-based BET and GW-ratio showed strong correlations with CL and demonstrated a diagnostic performance comparable to that of CL.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"40 8","pages":"983 - 998"},"PeriodicalIF":2.4,"publicationDate":"2026-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12149-026-02218-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147961817","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}