Search Results (278)

Background: Risk assessment in hyperthyroidism remains challenging. The aim of the present study is to determine the influence of hyperthyroid metabolic status on blood clotting and an increased risk of thrombosis. Methods: This prospective study included 50 patients after radical thyroidectomy and ablative radioiodine therapy because of thyroid carcinoma who were compared with 50 control subjects in a euthyroid metabolic state. Latent hyperthyroid patients with basal thyroid-stimulating hormone (TSH) ≤ 0.15 mU/L on levothyroxine hormone therapy were included. The control group was selected to match the patient group based on age and sex. The evaluation data were collected using laboratory coagulation tests and patient questionnaires. A bleeding and a thrombosis score were determined. Results: The coagulation parameters between the patient and control groups showed statistically significant differences. In particular, the patients’ group showed a significantly shortened activated partial thromboplastin time (aPTT/p = 0.009) and a significantly higher plasminogen activator inhibitor 1 (PAI-1/p < 0.001) compared to the control group. Age, sex, and medication use were not found to influence the patients’ laboratory results. Only body mass index was higher in the patient group than in the control group. Conclusions: Our results support a shift in the coagulation system in latent hyperthyroid metabolism towards increased coagulability and reduced fibrinolysis. A latent hyperthyroid metabolic state appears to be associated with an increased risk of thrombosis. Further prospective cohort studies with large patient populations are needed to verify the association between (latent) hyperthyroidism and thromboembolic events as well as to determine therapeutic anticoagulation or to adjust the indication for exogenous administration of thyroid hormone. Full article

Background: Lenvatinib is a receptor tyrosine kinase inhibitor indicated for advanced radioiodine-refractory thyroid cancer (RAI-RTC). It is recommended to start at 24 mg per day; however, in patients who are at risk of severe adverse events, it may be reasonable to start at lower doses. Patients and Methods: We included 15 patients with RAI-RTC who started lenvatinib at a very low/low dose and evaluated the efficacy and safety. Results: Eight patients (53.3%) did not show progression of the disease, and about half of the patients (53.3%) were alive at the last follow-up visit. Up to 26.6% of patients achieved a partial response to therapy, with a notable volume reduction in the local and metastatic lesions. However, 80% of patients experienced adverse events, mainly of a moderate grade. Conclusions: Although these findings are based on a small sample size and a single-center study, treatment with lenvatinib at very low/low doses in fragile patients seems to be a promising strategy for the management of RAI-RTC, balancing effective disease control with a favorable safety profile. Full article

This review focuses on the synthetic methodologies for radioiodinating peptides, a crucial process for developing effective radiopharmaceuticals used in diagnostics and therapeutics. We explore direct and indirect radioiodination methods, including mechanisms, reaction conditions, and purification strategies. The focus is on the chemical approaches that enable radioiodine incorporation into peptide structures, considering the challenges of maintaining peptide integrity and biological activity. This article is intended as a detailed resource for understanding traditional approaches and recent chemical developments in radioiodination. Full article

Background and Objectives: Thyroid nodules are a common endocrine disorder, with 10–15% exhibiting malignancy. Accurate differentiation of malignant and benign nodules is crucial for optimizing treatment outcomes. Current diagnostic tools, such as the Bethesda classification and fine-needle aspiration biopsy (FNAB), are limited in sensitivity and specificity, particularly in indeterminate cases. Tumor-infiltrating immune cells (TIICs) in the tumor microenvironment (TME) play a significant role in thyroid cancer progression. CD66b⁺ neutrophil-like monocytes constitute a novel subset of myeloid cells that are implicated in the modulation of anti-tumor immune responses, but their role in thyroid cancer remains unclear. Materials and Methods: Peripheral blood and thyroid nodule tissue samples were obtained from 24 patients with papillary thyroid carcinoma, and from 10 patients who underwent surgery for symptoms of tracheal compression due to benign thyroid nodules. Myeloid cell populations were assayed by flow cytometric immunophenotyping with CD45, HLA-DR, CD14, and CD66b. The data were statistically analyzed with the clinical properties of the patients. Results: The neutrophil-like monocytes, which were determined as HLA-DR⁺CD14⁺CD66b⁺ cells, found in the circulation (11.9 ± 2.4% of total mononuclear immune cells) of the patients with papillary thyroid carcinoma, were significantly elevated (p < 0.001). Accordingly, these cells were more frequently detected in tumor tissues (21.1 ± 2.1% of total tumor-infiltrating immune cells) compared to non-tumor thyroid tissues (p = 0.0231). The infiltration levels of neutrophil-like monocytes were significantly higher in malignant nodules as well as in the peripheral blood of the papillary thyroid carcinoma patients compared to the samples obtained from the patients with benign nodules. The tumor tissues exhibited increased immune cell infiltration and harbored CD66b-expressing neutrophil-like HLA-DR⁺CD14⁺ monocytic cells, which indicates an inflammatory milieu in malignant thyroid cancer. Conclusions: This study identifies neutrophil-like monocytes as a potential biomarker for differentiating malignant and benign thyroid nodules. Elevated levels of this novel subtype of immune cells in malignant tissues suggest their role in tumor progression and their utility in enhancing diagnostic accuracy. Incorporating these findings into clinical practice may refine surgical decision-making and improve outcomes through personalized diagnostic and therapeutic strategies, particularly for radioiodine-refractory thyroid cancer. Full article

The prostate-specific membrane antigen (PSMA) is a well-established target for radiotheranostics in prostate cancer. We previously demonstrated that 4-(p-astatophenyl)butyric acid (APBA), an albumin-binding moiety (ABM) labeled with astatine-211 (²¹¹At), enables the modulation of pharmacokinetics and enhancement of therapeutic efficacy when combined with the post-administration of an albumin-binding competitor. However, this strategy has not been explored in PSMA-targeting ligands. We designed and synthesized [²¹¹At]6, a novel PSMA ligand structurally analogous to PSMA-617 with APBA. The compound was obtained via a tin–halogen exchange reaction from the corresponding tributylstannyl precursor. Comparative cellular uptake and biodistribution studies were conducted with [²¹¹At]6, its radioiodinated analog [¹²⁵I]5, and [⁶⁷Ga]Ga-PSMA-617. To assess pharmacokinetic modulation, sodium 4-(p-iodophenyl)butanoate (IPBA), an albumin-binding competitor, was administered 1 h postinjection of [¹²⁵I]5 and [²¹¹At]6 at a 10-fold molar excess relative to blood albumin. The synthesis of [²¹¹At]6 gave a radiochemical yield of 15.9 ± 7.7% and a radiochemical purity > 97%. The synthesized [²¹¹At]6 exhibited time-dependent cellular uptake and internalization, with higher uptake levels than [⁶⁷Ga]Ga-PSMA-617. Biodistribution studies of [²¹¹At]6 in normal mice revealed a prolonged blood retention similar to those of [¹²⁵I]5. Notably, post-administration of IPBA significantly reduced blood radioactivity and non-target tissue accumulation of [¹²⁵I]5 and [²¹¹At]6. We found that ABM-mediated pharmacokinetic control was applicable to PSMA-targeted radiotherapeutics, broadening its potential for the optimization of radiotheranostics. Full article

Background/Objectives: Positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are highly sensitive clinical imaging modalities, frequently employed in conjunction with magnetic resonance imaging (MRI) or computed tomography (CT) for diagnosing a wide range of disorders. Efficient and robust radiolabeling methods are needed to accommodate the increasing demand for PET and SPECT tracer development. Copper-mediated radiohalogenation (CMRH) reactions enable rapid late-stage preparation of radiolabeled arenes, yet synthetic challenges and radiolabeling precursors’ instability can limit the applications of CMRH approaches. Methods: A series of aryl-boronic acids were converted into their corresponding aryl-boronic acid 1,1,2,2-tetraethylethylene glycol esters [ArB(Epin)s] and aryl-boronic acid 1,1,2,2-tetrapropylethylene glycol esters [ArB(Ppin)s] as stable and versatile precursor building blocks for radiolabeling via CMRH. General protocols for the preparation of ¹⁸F-labeled and ¹²³I-labeled arenes utilizing CMRH of these substrates were developed and applied. The radiochemical conversions (RCC) were determined by radio-(U)HPLC. Results: Both ArB(Epin)s and ArB(Ppin)s-based radiolabeling precursors were prepared in a one-step synthesis with chemical yields of 49–99%. Radiolabeling of the aryl-boronic esters with fluorine-18 or iodine-123 via CMRH furnished the corresponding radiolabeled arenes with RCC of 7–99% and 10–99%, respectively. Notably, a radiohalogenated prosthetic group containing a vinyl sulfone motif was obtained with an activity yield (AY) of 18 ± 3%, and applied towards the preparation of two clinically relevant PET tracers. Conclusions: This approach enables the synthesis of stable radiolabeling precursors and thus provides increased versatility in the application of CMRH, thereby supporting the development of novel PET and SPECT radiotracers. Full article

A previous cross-sectional study found impaired health-related quality of life (HRQoL) in hyperthyroid cats, but the longitudinal impact of treatment—especially differences between radioiodine (RAIT) and antithyroid drug (ATD) approaches—remains unclear. This study aimed to evaluate changes in HRQoL in recently diagnosed (<6 months) hyperthyroid cats that underwent RAIT or received ATD. HRQoL was assessed using the validated HyperthyroidismQoL-cat questionnaire at baseline and after 1, 3, and 6 months, alongside thyroid status (eu-/hypo-/hyperthyroid) evaluation. Mixed-effects model analysed the influence of treatment type, timepoint, and thyroid status on log(HRQoL). HRQoL differences between groups at baseline and comparison to a non-hyperthyroid control group (n = 322) from a previous study at month 6 were examined using Mann–Whitney U tests. Data are presented as median (range), with significance set at p < 0.05. Thirty-eight client-owned hyperthyroid cats (15 ATD, 23 RAIT) were included. HRQoL scores at baseline did not differ between groups (RAIT: 103.5 [27–211], ATD: 73 [22–260], p = 0.22). HRQoL significantly improved over time (p < 0.001) but was not affected by treatment type (p = 0.20) or thyroid status (p = 0.40). Despite improvement, HRQoL remained lower than in non-hyperthyroid controls (hyperthyroid: 42.5 [3–161.5], non-hyperthyroid: 27 [0–249], p = 0.007). This study highlights the overall positive impact of treatment on HRQoL, but due to the lack of randomisation and heterogeneity of subjects and treatment, conclusion have to be considered preliminary. Full article

Radioactive iodine therapy has been a well-established treatment for various thyroid conditions since the 1940s, targeting both benign diseases and malignancies. Treatment for benign conditions typically involves low doses of 131I, often requiring no more than two treatments, with the dose either fixed or personalized based on thyroid tissue mass and iodine uptake. In contrast, differentiated thyroid cancer treatment often requires higher doses and multiple administrations, especially for metastatic cases. Recent guidelines and studies have proposed more conservative management strategies, including careful follow-up, due to concerns over the high risk–benefit ratio in selected cases with a low risk of disease recrudescence. Despite its possible efficacy, radioiodine therapy is associated with dose-dependent side effects, the most common of which is salivary gland dysfunction or inflammation, affecting approximately 30% of adult patients. These effects pose significant challenges in nuclear medicine practice. This review aims to summarize the latest evidence on the incidence, impact on quality of life, prevention strategies and the role of these side effects in the decision-making process regarding RAI therapy. Full article

Therapy with radioactive iodine (I-131) following a total thyroidectomy has been a gold standard in the treatment of differentiated thyroid cancer (DTC) for over 80 years. Over the years, its role has shifted from routine use to a more selective, risk-adapted approach, informed by tumor biology, patient risk stratification and evolving clinical guidelines. This review examines the changing landscape of I-131 therapy, tracing its historical foundations, current indications, and future directions shaped by molecular medicine. We discuss the transition from a standardized, one-size-fits-all treatment approach to an individualized, dynamic stratification model that allows for ongoing risk reassessment and tailored treatment strategies. Key updates in clinical practice, such as the 2015 ATA Guidelines, the 2022 ETA Consensus Statement, and joint SNMMI and EANM nuclear medicine recommendations, are critically examined. We also address ongoing controversies in the management of low- and intermediate-risk patients, including the roles of I-131 whole-body scanning, activity selection, and overall treatment approach. Molecular theranostics is ushering in a new era in DTC management, enabling improved patient selection and more precise treatment. Advances in molecular profiling, imaging, and targeted therapies support a personalized treatment approach that aims to optimize therapeutic decisions while minimizing side effects and enhancing long-term safety. Full article

Thyroid cancer (TC) remains a prevalent malignancy, with over 820,000 global cases diagnosed in 2022. Differentiated thyroid carcinoma (DTC), primarily papillary and follicular types, accounts for most cases and has a favorable prognosis with total thyroidectomy and radioiodine (RAI) ablation. However, 5–15% of patients develop RAI-refractory (RAI-R) disease, leading to a significantly poorer outcome. For RAI-R patients, treatment decisions depend on disease progression. Active surveillance is suitable for indolent cases, while symptomatic or progressive disease requires systemic therapy. Multikinase inhibitors (MKIs) such as lenvatinib and sorafenib serve as first-line options, with cabozantinib recently approved for resistant cases. Additionally, novel targeted therapies, including RET and NTRK inhibitors, and immune checkpoint inhibitors, are under investigation, offering a personalized approach. A key challenge is determining the optimal timing for systemic therapy, balancing progression-free survival (PFS) benefits against MKI-related toxicities, which significantly impact quality of life (QoL). Molecular testing can identify actionable mutations, guiding therapy selection. Clinical guidelines (ATA, ESMO) recommend initiating treatment based on disease progression and patient condition, integrating strategies such as active surveillance, surgery, and radiotherapy when appropriate. Despite advances, systemic therapies carry significant adverse events (e.g., hypertension, fatigue, gastrointestinal toxicity), necessitating careful monitoring to prevent dose reductions or interruptions. A multidisciplinary approach is essential to optimize patient outcomes and maintain QoL. As targeted therapies continue to evolve, further research is needed to refine treatment sequencing and improve outcomes for RAI-R TC. This review synthesizes current evidence to guide clinical decision-making. Full article

Thyroid scintigraphy is a key tool for diagnosing and staging hyperthyroidism in cats, but follow-up scintigraphic studies after radioiodine treatment are limited. This multicentric study evaluated ^99mTc-pertechnetate scintigraphy findings in 234 hyperthyroid cats before and 6 months after radioiodine treatment. Based on serum T4 and TSH concentrations, 165 (70.5%) became euthyroid, 54 (23.1%) had subclinical hypothyroidism, and 15 (6.4%) developed overt hypothyroidism. On post-treatment scintigraphy, all cats showed reduced size and radionuclide uptake of “hot” thyroid nodules. Of 99 cats with unilateral nodules, 60 (61%) recovered function in the contralateral lobe. Among 135 cats with bilateral nodules, both lobes remained visible in 108 (80%). Persistent “hot” nodules with high thyroid/salivary (T/S) ratios or thyroidal pertechnetate uptake (TcTU) occurred in 26 (11%) cats, all of which were euthyroid. Conversely, 24 (10.4%) cats had minimal or absent thyroid tissue with 17 (71%) being hypothyroid, but seven (29%) were euthyroid. As a diagnostic test for iatrogenic hypothyroidism, TcTU showed the highest sensitivity (62.3), with the T/S ratio (7.3) and background-corrected T/S ratio (30.4) being much lower (p < 0.01). While follow-up scintigraphy aids in assessing thyroid tumor destruction and residual function, its diagnostic utility for differentiating euthyroidism and hypothyroidism is limited, especially for cats with mild (subclinical) hypothyroidism. Full article

Radioiodine (RAI) treatment (RAIT) is considered the gold standard for treatment of feline hyperthyroidism. This study aimed to assess owners’ motivation, concerns and satisfaction with RAIT and health-related quality of life (HRQoL) changes in RAI-treated cats. Two surveys (before and six months post-RAIT) were sent to owners of cats scheduled for RAIT between April 2023 and March 2024. The owners of 78 and 68 cats completed the first and the second surveys, respectively. The main reasons for choosing RAIT were that RAIT was considered the gold standard treatment (n = 27/78; 35%) and difficulties administering antithyroid drugs (n = 18/78; 23%). The primary care veterinarian (n = 50/78; 64%) and the internet (n = 33/78; 42%) were the main information sources about RAIT at the referral clinic. Owners were mostly concerned about the anaesthetic risk and hospitalisation, with the cat missing the owner and vice versa being the main worries. Most owners were satisfied with the outcome and their decision for RAIT. The HRQoL score improved within the first six months after RAIT (p < 0.01), with no difference between euthyroid and hypothyroid cats (p = 0.609). This study emphasises the role of the primary care veterinarian and the internet as primary sources of information regarding RAIT. The findings help to better understand owner concerns, improve owner counselling, and educate primary care veterinarians about RAIT. Full article

The clinicopathological and molecular features of synchronous parathyroid carcinoma (PC) and thyroid carcinoma in a male patient are presented. At 11, he received mantle field radiotherapy for Hodgkin lymphoma. He had a 26-year adulthood history of recurrent nephrolithiasis treated five times with lithotripsy. At 52, he was referred to our clinic for hypercalcemia. Primary hyperparathyroidism was diagnosed (calcium: 3.46 mmol/L, parathormone: 150 pmol/L, preserved renal function, nephrolithiasis, and osteoporosis). Neck ultrasound revealed a 41 × 31 × 37 mm nodule in the left thyroid and smaller nodules in the right thyroid. Enlarged cervical lymph nodes were not observed. The large nodule was interpreted as parathyroid adenoma on 99Tc-pertechnetate scintigraphy/99Tc-MIBI scintigraphy with SPECT/CT. Total left-sided and subtotal right-sided thyroidectomy were performed. Histopathology confirmed locally invasive, low-grade PC (pT2; positive for parafibromin and E-cadherin, negative for galectin-3 and PGP9.5; wild-type expression for p53 and retinoblastoma protein; Ki-67 index 10%) and incidental papillary thyroid carcinoma (pT1b). Genetic profiling revealed no loss in CDC73, MEN1, CCND1, PIK3CA, CDH1, RB1, and TP53 genes. Deletions in CDKN2A, LATS1, ARID1A, ARID1B, RAD54L, and MUTYH genes and monosomies in nine chromosomes were identified. The tumor mutational burden and genomic instability score were low, and the tumor was microsatellite-stable. The thyroid carcinoma exhibited a TRIM24::BRAF fusion. Following surgery, the parathormone and calcium levels had normalized, and the patient underwent radioiodine treatment for thyroid cancer. The follow-up of 14 months was eventless. In summary, the clinical, laboratory, and imaging features of hyperparathyroidism taken together could have suggested malignancy, then confirmed histologically. The synchronous carcinomas were most likely caused by irradiation treatment diagnosed 41 years after exposure. It seems that the radiation injury initially induced parathyroid adenoma in young adulthood, which underwent a malignant transformation around age fifty. Full article

Background: The understanding of the molecular basis of paediatric thyroid carcinoma has expanded rapidly in the last decade. Most carcinomas are associated with de novo somatic gene alterations that confer distinct clinicopathological characteristics. In comparison to adults, paediatric carcinomas are less commonly associated with point mutations and more commonly with gene fusions, which are characterised by more-invasive disease. Cancer predisposition genes play an important role in a small percentage of tumours, and the family history and the recognition of other syndromic features are key to identifying these patients. Molecular testing platforms for clinical use have been developed and validated in adults, and their use is becoming established in the management of indeterminate thyroid nodules, where they significantly reduce the rates of diagnostic lobectomy. Paediatric data are more limited than adult data, and the role of molecular testing in paediatric thyroid carcinoma management is evolving. Methods: This review describes the current knowledge of molecular alterations in paediatric thyroid carcinomas, evidence supporting molecular testing in clinical practice, and future directions for research. Results and Conclusions: A molecular diagnosis enables the use of molecularly targeted therapies for children and adolescents with advanced or radioiodine-refractory disease. There is also great potential for molecular testing to improve the accuracy of the risk-stratification of paediatric thyroid nodules, reducing surgical intervention and complications without negatively impacting outcomes, and data to support such an approach are emerging. Full article

Background/Objectives: Integrin α_Vβ₃ plays a crucial role in tumor angiogenesis and cancer progression, making it a key target for radiolabeled probes used in imaging and therapy. A previously developed probe, [¹²⁵I]bcRGD, exhibited high selectivity for α_Vβ₃ but limited tumor accumulation due to rapid blood clearance. This study aimed to address this issue through two strategies: (1) conjugating albumin-binding molecules to enhance systemic circulation and (2) dimerizing RGD peptides to improve binding affinity via multivalency effects. Methods: Three [¹²⁵I]bcRGD derivatives were synthesized: [¹²⁵I]bcRGD_pal (with palmitic acid), [¹²⁵I]bcRGD_iba (with 4-(p-iodophenyl)butyric acid), and [¹²⁵I]bcRGD_dimer (a dimeric bicyclic RGD peptide). Their physicochemical properties, α_Vβ₃-selectivity, albumin-binding capacity, and biodistribution were assessed in vitro and in vivo using tumor-bearing mice. Tumor models included α_Vβ₃-high U-87 MG and α_Vβ₃-low A549 xenografts. Results: [¹²⁵I]bcRGD_pal and [¹²⁵I]bcRGD_iba exhibited prolonged blood retention (30-fold and 55-fold vs. [¹²⁵I]bcRGD, respectively) and increased tumor accumulation (3.9% ID/g and 3.6% ID/g at 2 h, respectively). Despite improved systemic circulation, tumor-to-blood ratios remained low (<1), indicating limited tumor retention. [¹²⁵I]bcRGD_dimer achieved significantly greater tumor accumulation (4.2% ID/g at 2 h) and favorable tumor-to-blood (22) and tumor-to-muscle (14) ratios, with a 5.4-fold higher uptake in U-87 MG tumors compared to A549 tumors. Conclusions: Dimerization was more effective than albumin binding in enhancing bcRGD’s tumor-targeting potential. The dimeric probe demonstrated improved tumor accumulation, favorable pharmacokinetics, and preserved integrin selectivity. These findings provide a foundation for further structural optimization of bicyclic RGD peptides for integrin α_Vβ₃-targeted imaging and therapy applications. Full article