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1.
Eur J Nucl Med Mol Imaging ; 51(8): 2428-2441, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38528164

RESUMO

PURPOSE: To evaluate the dosimetry and pharmacokinetics of the novel radiolabelled somatostatin receptor antagonist [177Lu]Lu-satoreotide tetraxetan in patients with advanced neuroendocrine tumours (NETs). METHODS: This study was part of a phase I/II trial of [177Lu]Lu-satoreotide tetraxetan, administered at a median cumulative activity of 13.0 GBq over three planned cycles (median activity/cycle: 4.5 GBq), in 40 patients with progressive NETs. Organ absorbed doses were monitored at each cycle using patient-specific dosimetry; the cumulative absorbed-dose limits were set at 23.0 Gy for the kidneys and 1.5 Gy for bone marrow. Absorbed dose coefficients (ADCs) were calculated using both patient-specific and model-based dosimetry for some patients. RESULTS: In all evaluated organs, maximum [177Lu]Lu-satoreotide tetraxetan uptake was observed at the first imaging timepoint (4 h after injection), followed by an exponential decrease. Kidneys were the main route of elimination, with a cumulative excretion of 57-66% within 48 h following the first treatment cycle. At the first treatment cycle, [177Lu]Lu-satoreotide tetraxetan showed a median terminal blood half-life of 127 h and median ADCs of [177Lu]Lu-satoreotide tetraxetan were 5.0 Gy/GBq in tumours, 0.1 Gy/GBq in the bone marrow, 0.9 Gy/GBq in kidneys, 0.2 Gy/GBq in the liver and 0.8 Gy/GBq in the spleen. Using image-based dosimetry, the bone marrow and kidneys received median cumulative absorbed doses of 1.1 and 10.8 Gy, respectively, after three cycles. CONCLUSION: [177Lu]Lu-satoreotide tetraxetan showed a favourable dosimetry profile, with high and prolonged tumour uptake, supporting its acceptable safety profile and promising efficacy. TRIAL REGISTRATION: NCT02592707. Registered October 30, 2015.


Assuntos
Tumores Neuroendócrinos , Humanos , Tumores Neuroendócrinos/radioterapia , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/metabolismo , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Adulto , Radiometria , Lutécio/farmacocinética , Distribuição Tecidual , Somatostatina/análogos & derivados , Somatostatina/farmacocinética , Progressão da Doença , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/uso terapêutico , Idoso de 80 Anos ou mais , Octreotida/análogos & derivados , Octreotida/farmacocinética , Octreotida/uso terapêutico , Radioisótopos
2.
Eur J Nucl Med Mol Imaging ; 51(1): 183-195, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37721581

RESUMO

PURPOSE: We present the results of an open-label, phase I/II study evaluating the safety and efficacy of the novel somatostatin receptor (SSTR) antagonist [177Lu]Lu-satoreotide tetraxetan in 40 patients with previously treated, progressive neuroendocrine tumours (NETs), in which dosimetry was used to guide maximum administered activity. METHODS: This study was conducted in two parts. Part A consisted of 15 patients who completed three cycles of [177Lu]Lu-satoreotide tetraxetan at a fixed administered activity and peptide amount per cycle (4.5 GBq/300 µg). Part B, which included 25 patients who received one to five cycles of [177Lu]Lu-satoreotide tetraxetan, evaluated different administered activities (4.5 or 6.0 GBq/cycle) and peptide amounts (300, 700, or 1300 µg/cycle), limited to a cumulative absorbed radiation dose of 23 Gy to the kidneys and 1.5 Gy to the bone marrow. RESULTS: Median cumulative administered activity of [177Lu]Lu-satoreotide tetraxetan was 13.0 GBq over three cycles (13.1 GBq in part A and 12.9 GBq in part B). Overall, 17 (42.5%) patients experienced grade ≥ 3 treatment­related adverse events; the most common were lymphopenia, thrombocytopenia, and neutropenia. No grade 3/4 nephrotoxicity was observed. Two patients developed myeloid neoplasms considered treatment related by the investigator. Disease control rate for part A and part B was 94.7% (95% confidence interval [CI]: 82.3-99.4), and overall response rate was 21.1% (95% CI: 9.6-37.3). CONCLUSION: [177Lu]Lu-satoreotide tetraxetan, administered at a median cumulative activity of 13.0 GBq over three cycles, has an acceptable safety profile with a promising clinical response in patients with progressive, SSTR-positive NETs. A 5-year long-term follow-up study is ongoing. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02592707. Registered October 30, 2015.


Assuntos
Tumores Neuroendócrinos , Compostos Organometálicos , Humanos , Tumores Neuroendócrinos/radioterapia , Tumores Neuroendócrinos/tratamento farmacológico , Receptores de Somatostatina , Octreotida/efeitos adversos , Seguimentos , Compostos Organometálicos/efeitos adversos
3.
Endocr Res ; 43(1): 11-14, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28742421

RESUMO

PURPOSE OF THE STUDY: To compare efficacy of thyroid remnant ablation using 30 mCi or 50 mCi 131-I in papillary thyroid cancer patients. MATERIALS AND METHODS: Five hundred and fifteen consecutive patients with Tumor-Node-Metastasis (TNM) stages T1-T3 N1/N0/NX receiving either 30 mCi or 50 mCi I-131 were analyzed for the effectiveness of remnant ablation using rhTSH-stimulated serum thyroglobulin. One hundred and five consecutive patients receiving 100 mCi I-131 were analyzed for the incidence of radiation thyroiditis and sialadenitis. RESULTS AND CONCLUSIONS: Doses of 30 mCi and 50 mCi were equally effective for low- and moderate-risk disease but 30 mCi was less effective for T1T2NX disease, and 50 mCi was less effective for T3 compared to T1T2 disease. Low dose radiation hypersensitivity or unknown more extensive disease may have accounted for observed differences. Radiation thyroiditis and sialadenitis were more common in a comparison series of 100 mCi dose compared to 30 mCi, but not more common than in 50 mCi doses.


Assuntos
Técnicas de Ablação/efeitos adversos , Técnicas de Ablação/métodos , Carcinoma Papilar/radioterapia , Radioisótopos do Iodo/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Sialadenite/etiologia , Neoplasias da Glândula Tireoide/radioterapia , Tireoidite/etiologia , Adulto , Humanos , Radioisótopos do Iodo/administração & dosagem , Radioisótopos do Iodo/efeitos adversos , Estadiamento de Neoplasias , Estudos Retrospectivos , Câncer Papilífero da Tireoide
4.
Can J Surg ; 60(3): 192-197, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28327275

RESUMO

BACKGROUND: Neuroendocrine tumours (NETs) are heterogeneous, with varying presentations and treatment options. To our knowledge, there are no randomized and few long-term studies of patient outcomes. The role of surgical and medical therapy for local, regional and metastatic disease continues to be evaluated in the literature. METHODS: We conducted a population-based search of the provincial cancer registry to identify patients with gastrointestinal NETs from the stomach, small intestine, colon and rectum diagnosed between 1990 and 2005 and assessed their outcomes. RESULTS: We examined clinicopathological information on the outcomes of 530 patients with gastrointestinal NETs. The overall incidence of NETs increased from 11 per million to 19 per million during the study period. Advancing stage and patient age were associated with poor overall or disease-specific outcomes. Surgery, both curative and palliative, was associated with decreased risk of overall (hazard ratio [HR] 0.5, p < 0.001) and disease-specific (HR 0.5, p < 0.001) death. The biggest benefit was observed in patients with distant disease, in whom 5-year disease-specific survival for R0 resections was nearly double that for patients with macroscopic residual disease (92% v. 48%, p = 0.009). Older age was associated with poor 5-year overall and disease-specific survival (p < 0.001). CONCLUSION: There has been a significant increase in incidence of gastrointestinal NETs, and advancing patient age, but not sex, is linked to poor outcomes in terms of overall and disease-specific survival. Surgery, both curative and palliative, was associated with decreased risk of overall and disease-specific death. Compared with patients with residual macroscopic disease, patients with distant disease were nearly twice as likely to survive 5 years if they had R0 resections. The use of radioisotope therapy and long-acting octreotide therapy was also associated with improved outcomes overall.


CONTEXTE: Les tumeurs neuroendocrines (TNE) sont hétérogènes, et les tableaux et options thérapeutiques sont variables. À notre connaissance, il n'existe pas d'études randomisées et il y a peu d'études à long terme sur les résultats chez les patients. Le rôle du traitement chirurgical et médicamenteux de la maladie locale, régionale et métastatique continue d'être évalué dans la littérature. MÉTHODES: Nous avons procédé à une interrogation démographique du Registre provincial du cancer pour recenser les patients atteints de TNE gastro-intestinales provenant de l'estomac, de l'intestin grêle, du côlon et du rectum, diagnostiqués entre 1990 et 2005 et nous avons évalué les résultats. RÉSULTATS: Nous avons examiné les données clinico-pathologiques des résultats enregistrés chez 530 patients atteints de TNE gastro-intestinales. L'incidence globale des TNE a augmenté de 11 par million à 19 par million pendant la période de l'étude. Le stade de la maladie et l'âge avancés ont été associés à des résultats globaux ou spécifiques à la maladie moins favorables. La chirurgie, curative et palliative, a été associée à un risque moindre de décès global (risque relatif [RR] 0.5, p < 0,001) et spécifique à la maladie (RR 0,5, p < 0,001). L'avantage le plus marqué a été observé chez les patients présentant une maladie distale, chez qui la survie à 5 ans spécifique à la maladie pour les résections R0 était près de 2 fois celle des patients présentant une maladie macroscopique résiduelle (92 % c. 48 %, p = 0,009). L'âge avancé a été associé à une survie à 5 ans globale et spécifique à la maladie défavorable (p < 0,001). CONCLUSION: L'incidence des TNE gastro-intestinales a significativement augmenté, et l'âge avancé des patients, mais non le sexe, est lié à des résultats défavorables aux plans de la survie globale et spécifique à la maladie. La chirurgie, curative et palliative, a été associée à un risque moindre de décès global et spécifique à la maladie. Comparativement aux patients ayant une maladie macroscopique résiduelle, ceux qui avaient une maladie distale étaient près de 2 fois plus susceptibles de survivre 5 ans s'ils avaient des résections R0. Les traitements par radio-isotopes et octréotide à longue durée d'action ont aussi été associés à une amélioration globale des résultats.


Assuntos
Neoplasias Gastrointestinais , Tumores Neuroendócrinos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alberta/epidemiologia , Criança , Intervalo Livre de Doença , Feminino , Seguimentos , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/mortalidade , Neoplasias Gastrointestinais/terapia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/terapia , Adulto Jovem
5.
Invest New Drugs ; 33(3): 603-10, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25762000

RESUMO

Purpose Preclinical evidence suggests dichloroacetate (DCA) can reverse the Warburg effect and inhibit growth in cancer models. This phase 1 study was undertaken to assess the safety, recommended phase 2 dose (RP2D), and pharmacokinetic (PK) profile of oral DCA in patients with advanced solid tumors. Patients and Methods Twenty-four patients with advanced solid malignancies were enrolled using a standard 3 + 3 protocol at a starting dose of 6.25 mg/kg twice daily (BID). Treatment on 28 days cycles was continued until progression, toxicity, or consent withdrawal. PK samples were collected on days 1 and 15 of cycle 1, and day 1 of subsequent cycles. PET imaging ((18) F-FDG uptake) was investigated as a potential biomarker of response. Results Twenty-three evaluable patients were treated with DCA at two doses: 6.25 mg/kg and 12.5 mg/kg BID (median of 2 cycles each). No DLTs occurred in the 6.25 mg/kg BID cohort so the dose was escalated. Three of seven patients had DLTs (fatigue, vomiting, diarrhea) at 12.5 mg/kg BID. Thirteen additional patients were treated at 6.25 mg/kg BID. Most toxicities were grade 1-2 with the most common being fatigue, neuropathy and nausea. No responses were observed and eight patients had stable disease. The DCA PK profile in cancer patients was consistent with previously published data. There was high variability in PK values and neuropathy among patients. Progressive increase in DCA trough levels and a trend towards decreased (18) F-FDG uptake with length of DCA therapy was observed. Conclusions The RP2D of oral DCA is 6.25 mg/kg BID. Toxicities will require careful monitoring in future trials.


Assuntos
Ácido Dicloroacético/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Adulto , Idoso , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Estudos de Coortes , Ácido Dicloroacético/efeitos adversos , Ácido Dicloroacético/farmacocinética , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/metabolismo
6.
Endocr Res ; 39(4): 157-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24460082

RESUMO

INTRODUCTION: The study was aimed to determine the response and predictive risk factors of differentiated thyroid cancer (DTC) with measurable (0.4-2.0 µg/L) stimulated serum thyroglobulin (sTg) during the 10-24 months after radioiodine remnant ablation (RRA) and their long-term outcomes. METHODS: Out of 839 retrospectively reviewed patients, 95 eligible DTC patients were included. Patients were classified as having incomplete response or no evidence of disease (NED). The sTg cut-off values with highest predicted accuracy for incomplete response at 10-24 months were calculated with receiver operator characteristics curve analysis. RESULTS AND CONCLUSION: At 10-24 months after RRA, incomplete response was identified in 54 patients (57%) and 38/54 (70.4%) patients were found with structural evidence of disease. The remaining 16 patients (29.6%) had biochemical evidence of disease without structural evidence of disease. Forty-one patients (43%) were classified as having NED at 10-24 months after RRA and 27 patients (66%) did not receive further radioactive iodine (RAI) therapy and remained disease free at median follow-up of 6.5 years. Fourteen patients received second RAI treatment after 6 months and before the 10-24 months assessment time point. Of these, 2 had persistent tumor 6 years later. The sTg >0.6 µg/L at 6-10 months after RRA had optimal sensitivity (83.3%), specificity (56%) and negative predictive value (72%) of detecting incomplete response at 10-24 months after RRA. A total of 23/43 patients in the American Thyroid Association low-risk category had incomplete response after first RRA and 5/23 (21.7%) had recurrent/persistent disease at long-term follow-up.


Assuntos
Recidiva Local de Neoplasia/diagnóstico , Tolerância a Radiação , Compostos Radiofarmacêuticos/uso terapêutico , Tireoglobulina/sangue , Glândula Tireoide/efeitos da radiação , Neoplasias da Glândula Tireoide/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Terapia Combinada , Feminino , Seguimentos , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Neoplasia Residual , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tireoglobulina/metabolismo , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Carga Tumoral/efeitos da radiação , Adulto Jovem
7.
Front Oncol ; 12: 812777, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875083

RESUMO

In 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) studies, maximum standardized uptake value (SUVmax) is the parameter commonly used to provide a measurement of the metabolic activity of a tumor. SUV normalized by body mass is affected by the proportions of body fat and lean tissue, which present high variability in patients with cancer. SUV corrected by lean body mass (LBM), denoted as SUL, is recommended to provide more accurate, consistent, and reproducible SUV results; however, LBM is frequently estimated rather than measured. Given the increasing importance of a quantitative PET parameter, especially when comparing PET studies over time to evaluate disease response clinically, and its use in oncological clinical trials, we set out to evaluate the commonly used equations originally derived by James (1976) and Janmahasatian et al. (2005) against computerized tomography (CT)-derived measures of LBM. Methods: Whole-body 18F-FDG PET images of 195 adult patients with cancer were analyzed retrospectively. Representative liver SUVmean was normalized by total body mass. SUL was calculated using a quantitative determination of LBM based on the CT component of the PET/CT study (LBMCT) and compared against the equation-estimated SUL. Bland and Altman plots were generated for SUV-SUL differences. Results: This consecutive sample of patients undergoing usual care (men, n = 96; women, n = 99) varied in body mass (38-127 kg) and in Body Mass Index (BMI) (14.7-47.2 kg/m2). LBMCT weakly correlated with body mass (men, r2 = 0.32; women, r2 = 0.22), and thus SUV and SULCT were also weakly correlated (men, r2 = 0.24; women, r2 = 0.11). Equations proved inadequate for the assessment of LBM. LBM estimated by James' equation showed a mean bias (overestimation of LBM compared with LBMCT) in men (+6.13 kg; 95% CI 4.61-7.65) and in women (+6.32 kg; 95% CI 5.26-7.39). Janmahasatian's equation provided similarly poor performance. Conclusions: CT-based LBM determinations incorporate the patient's current body composition at the time of a PET/CT study, and the information garnered can provide care teams with information with which to more accurately determine FDG uptake values, allowing comparability over multiple scans and treatment courses and will provide a robust basis for the use of PET Response Criteria in Solid Tumors (PERCIST) in clinical trials.

8.
Pharmaceutics ; 14(8)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36015281

RESUMO

Theragnostic pairs of isotopes are used to infer radiation dosimetry for a therapeutic radiopharmaceutical from a diagnostic imaging study with the same tracer molecule labelled with an isotope better suited for the imaging task. We describe the transfer of radiation dosimetry from the diagnostic radioiodine isotope 123I, labelled for the hypoxia tracer molecule iodoazomycin arabinoside ([123I]IAZA), to isotopes 131I (therapeutic) and 124I (PET imaging). Uncertainties introduced by the dissimilar isotope half-lives are discussed in detail. Radioisotope dosimetries for [123I]IAZA were obtained previously. These data are used here to calculate residence times for 131I and 124I and their uncertainties. We distinguish two cases when extrapolating to infinity: purely physical decay (case A) and physical decay plus biological washout (case B). Organ doses were calculated using the MIRD schema with the OLIDNA/EXM code. Significant increases in some organ doses (in mSv per injected activity) were found for 131I and 124I. The most affected organs were the intestinal walls, thyroid, and urinary bladder wall. Uncertainty remained similar to 123I for case A but considerably greater for case B, especially for long biological half-lives (GI tract). Normal tissue dosimetries for IAZA must be considered carefully when substituting isotope species. A long biological half-life can significantly increase dosimetric uncertainties. These findings are relevant when considering PET imaging studies with [124I]IAZA or therapeutic administration of [131I]IAZA.

9.
Psychiatry Res ; 316: 114770, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35961154

RESUMO

Social anxiety disorder (SAD) is very common and can be significantly disabling. New treatments are needed as the remission rate for SAD is the lowest of all the anxiety disorders. Experimental medicine models, in which features resembling a clinical disorder are experimentally induced, are a cost-effective and timely approach to explore potential novel treatments for psychiatric disorders. Following the emergence of SARS-CoV-2, there is a need to develop experimental medicine models that can be carried out remotely. We developed a novel procedure to investigate SAD (the InterneT-based Stress test for Social Anxiety Disorder; ITSSAD) that can be carried out entirely online by a single investigator, potentially reducing costs and maximising internal reliability. The procedure involves an anticipatory period followed by a naturalistic social interaction task. In a sample of 20 non-treatment-seeking volunteers with symptoms of SAD, the ITSSAD induced significant subjective anxiety and reduced positive affect. Further, increased social anxiety symptoms at baseline predicted increased anxiety during the social interaction task. This protocol needs further validation with physiological measures. The ITSSAD is a new tool for researchers to investigate mechanisms underlying social anxiety disorder.


Assuntos
COVID-19 , Fobia Social , Ansiedade/psicologia , Humanos , Fobia Social/psicologia , Reprodutibilidade dos Testes , SARS-CoV-2 , Software , Comunicação por Videoconferência
10.
Clin Transl Sci ; 14(3): 847-858, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33278334

RESUMO

Positron emission tomography (PET) using 2-deoxy-2-[18 F]fluoro-d-glucose ([18 F]FDG), a marker of energy metabolism and cell proliferation, is routinely used in the clinic to assess patient response to chemotherapy and to monitor tumor growth. Treatment with some tyrosine kinase inhibitors (TKIs) causes changes in blood glucose levels in both nondiabetic and diabetic patients. We evaluated the interaction of several classes of TKIs with human glucose transporter-1 (hGLUT-1) in FaDu and GIST-1 cells by measuring [3 H]2-deoxy-d-glucose ([3 H]2-DG) and [3 H]FDG uptake. Uptake of both was inhibited to varying extents by the TKIs, and representative TKIs from each class showed competitive inhibition of [3 H]2-DG uptake. In GIST-1 cells, [3 H]FDG uptake inhibition by temsirolimus and nilotinib was irreversible, whereas inhibition by imatinib, gefitinib, and pazopanib was reversible. Molecular modeling studies showed that TKIs form multiple hydrogen bonds with polar residues of the sugar binding site (i.e., Q161, Q282, Q283, N288, N317, and W388), and van der Waals interactions with the H-pocket site. Our results showed interaction of TKIs with amino acid residues at the glucose binding site to inhibit glucose uptake by hGLUT-1. We hypothesize that inhibition of hGLUT-1 by TKIs could alter glucose levels in patients treated with TKIs, leading to hypoglycemia and fatigue, although further studies are required to evaluate roles of other SLC2 and SLC5 members. In addition, TKIs could affect tumor [18 F]FDG uptake, increasingly used as a marker of tumor response. The hGLUT-1 inhibition by TKIs may have implications for routine [18 F]FDG-PET monitoring of tumor response in patients.


Assuntos
Fluordesoxiglucose F18/farmacologia , Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Inibidores de Proteínas Quinases/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Interações Medicamentosas , Transportador de Glucose Tipo 1/ultraestrutura , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica
11.
Bioorg Med Chem ; 18(6): 2255-2264, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20181485

RESUMO

The current work evaluates 1-alpha-d-(2-deoxy-2-fluororibofuranosyl)-2-nitroimidazole (FRAZ), a novel azomycin nucleoside that is a potential radiosensitizer of tumor hypoxia. FRAZ is a ribose analogue of 1-alpha-d-(2-deoxy-2-fluoroarabinofuranosyl)-2-nitroimidazole ([(18)F]-FAZA), a clinically used hypoxia marker. Preliminary assessment of the cytotoxicity and hypoxia-specific in vitro binding in HCT-110 colorectal cancer cells indicate that the radiosensitization properties of FRAZ are similar to that of FAZA, with a sensitizer enhancement ratio (SER) of approximately 1.8. An automated radiosynthesis of [(18)F]-FRAZ using a commercial automated synthesis unit (ASU) was established (synthesis time approximately 32 min; radiochemical yield (decay uncorrecetd) approximately 22%) to facilitate its application in PET-based diagnosis of hypoxic tumors.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Radioisótopos de Flúor/química , Hipóxia , Nitroimidazóis/farmacologia , Ribose/análogos & derivados , Antineoplásicos/síntese química , Antineoplásicos/química , Sítios de Ligação , Biomarcadores Tumorais/síntese química , Biomarcadores Tumorais/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/diagnóstico , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Marcação por Isótopo , Nitroimidazóis/síntese química , Nitroimidazóis/química , Tomografia por Emissão de Pósitrons , Ribose/síntese química , Ribose/química , Ribose/farmacologia
12.
Eur J Nucl Med Mol Imaging ; 36(10): 1565-73, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19430784

RESUMO

PURPOSE: Tumour hypoxia is thought to play a significant role in the outcome of solid tumour therapy. Positron emission tomography (PET) is the best-validated noninvasive technique able to demonstrate the presence of hypoxia in vivo. The locally developed PET tracer for imaging hypoxia, 1-alpha-D: -(5-deoxy-5-[(18)F]-fluoroarabinofuranosyl)-2-nitroimidazole ((18)F-FAZA), has been shown to accumulate in experimental models of tumour hypoxia and to clear rapidly from the circulation and nonhypoxic tissues. The safety and general biodistribution patterns of this radiopharmaceutical in patients with squamous cell carcinoma of the head and neck (HNSCC), small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC), malignant lymphoma, and high-grade gliomas, were demonstrated in this study. METHODS: Patients with known primary or suspected metastatic HNSCC, SCLC or NSCLC, malignant lymphoma or high-grade gliomas were dosed with 5.2 MBq/kg of (18)F-FAZA, then scanned 2-3 h after injection using a PET or PET/CT scanner. Images were interpreted by three experienced nuclear medicine physicians. The location and relative uptake scores (graded 0 to 4) of normal and abnormal (18)F-FAZA biodistribution patterns, the calculated tumour-to-background (T/B) ratio, and the maximum standardized uptake value were recorded. RESULTS: Included in the study were 50 patients (32 men, 18 women). All seven patients with high-grade gliomas showed very high uptake of (18)F-FAZA in the primary tumour. In six out of nine patients with HNSCC, clear uptake of (18)F-FAZA was observed in the primary tumour and/or the lymph nodes in the neck. Of the 21 lymphoma patients (15 with non-Hodgkin's lymphoma and 6 with Hodgkin's disease), 3 demonstrated moderate lymphoma-related uptake. Of the 13 lung cancer patients (12 NSCLC, 1 SCLC), 7 had increased (18)F-FAZA uptake in the primary lung tumour. No side effects of the administration of (18)F-FAZA were observed. CONCLUSION: This study suggests that (18)F-FAZA may be a very useful radiopharmaceutical to image hypoxia in the tumour types selected. Especially the high uptake by gliomas was encouraging. Given the good imaging properties, including acceptable T/B ratios in the tumour categories studied, (18)F-FAZA could be considered as a very promising agent for assessing the hypoxic fraction of these tumour types.


Assuntos
Hipóxia/diagnóstico por imagem , Neoplasias/diagnóstico por imagem , Nitroimidazóis , Compostos Radiofarmacêuticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma de Células Pequenas/diagnóstico por imagem , Carcinoma de Células Escamosas/diagnóstico por imagem , Feminino , Radioisótopos de Flúor , Glioma/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Adulto Jovem
13.
Clin Nucl Med ; 44(9): 719-727, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31205149

RESUMO

OBJECTIVE: The purpose of this study was to assess the efficacy of Lu-labeled peptide receptor radionuclide therapy (PRRT) induction treatments for patients with unresectable metastatic neuroendocrine tumors. METHODS: MEDLINE, EMBASE, and Ovid were systematically searched with keywords "lutetium," "Lu-177," "PRRT," "neuroendocrine," and "prognosis." Studies evaluating treatment with Lu-labeled PRRT were assessed for disease response and/or disease control rate by Response Evaluation Criteria in Solid Tumors (RECIST) 1.0 or 1.1, modified RECIST, Southwest Oncology Group (SWOG), or modified SWOG criteria. Pooled proportions of disease response and control rates were calculated for both fixed- and random-effects models. RESULTS: Eighteen studies with 1920 patients were included (11 with 1268 patients using RECIST and 6 with 804 patients using SWOG). By RECIST criteria, the pooled disease response rate by random-effects model was 29.1% (95% confidence interval [CI], 20.2%-38.9%), and disease control rate was 74.1% (95% CI, 67.8%-80.0%). By SWOG criteria, the pooled disease response rate by random-effects model was 30.6% (95% CI, 20.7%-41.5%), and disease control rate was 81.1% (95% CI, 76.4%-85.4%). CONCLUSIONS: Induction therapy, typically 4 treatments, with Lu PRRT is an effective method of treating unresectable metastatic neuroendocrine tumors with significant disease response and control rates.


Assuntos
Lutécio/uso terapêutico , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/radioterapia , Radioisótopos/uso terapêutico , Receptores de Peptídeos/metabolismo , Humanos , Terapia Neoadjuvante , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/patologia , Prognóstico
14.
Case Rep Oncol ; 12(3): 791-795, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31762750

RESUMO

Thyroid cancer is the most common type of endocrine malignancy. Cornerstones of thyroid cancer treatment include surgery, radioactive iodine ablation, and thyroid stimulating hormone suppression. The National Comprehensive Cancer Network guidelines recommend two tyrosine kinase inhibitors for thyroid cancer patients who are non-responsive to iodine: sorafenib and lenvatinib. Another oral kinase inhibitor, regorafenib, is not considered standard of care treatment for differentiated thyroid cancer. The chemical structures of regorafenib and sorafenib differ by a single fluorine atom. Given the significant improvement in progression-free survival (PFS) of sorafenib compared to placebo demonstrated in the phase 3 DECISION trial, we report on a patient with iodine-refractory follicular thyroid cancer treated with regorafenib as part of a phase 1 clinical trial. A 75 year old woman was diagnosed with follicular thyroid carcinoma in 2006 and initiated on treatment with regorafenib in 2011. She has completed 76 cycles with stable disease and pulmonary metastases 34% smaller than baseline.

15.
Small ; 4(9): 1537-43, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18712753

RESUMO

Gold nanoparticles (GNPs) and modified GNPs having two kinds of functional molecules, cysteamine (AET) and thioglucose (Glu), are synthesized. Cell uptake and radiation cytotoxicity enhancement in a breast-cancer cell line (MCF-7) versus a nonmalignant breast-cell line (MCF-10A) are studied. Transmission electron microscopy (TEM) results show that cancer cells take up functional Glu-GNPs significantly more than naked GNPs. The TEM results also indicate that AET-capped GNPs are mostly bound to the MCF-7 cell membrane, while Glu-GNPs enter the cells and are distributed in the cytoplasm. After MCF-7 cell uptake of Glu-GNPs, or binding of AET-GNPs, the in vitro cytotoxicity effects are observed at 24, 48, and 72 hours. The results show that these functional GNPs have little or no toxicity to these cells. To validate the enhanced killing effect on cancer cells, various forms of radiation are applied such as 200 kVp X-rays and gamma-rays, to the cells, both with and without functional GNPs. By comparison with irradiation alone, the results show that GNPs significantly enhance cancer killing.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Ouro/química , Ouro/farmacologia , Nanopartículas Metálicas/química , Neoplasias da Mama/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ouro/metabolismo , Humanos , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Sensibilidade e Especificidade , Análise Espectral
16.
Bioorg Med Chem Lett ; 18(11): 3256-60, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18479915

RESUMO

Stereospecific synthesis of 1-alpha-d-(2-deuteroribofuranosyl)-2-nitroimidazole (2'-[(2)H]-alpha-AZR) is reported. This, deuteration was independent of the configuration of C-2' -OH group (arabinose or ribose) in sugar moiety of starting molecules. Slightly better yield (>37%) of the deuterated product, 6, from arabinosyl precursor in comparison to corresponding ribose precursor (29%) was obtained which may reflect better stereochemical availability of C-2' -OH in arabinose during oxidation.


Assuntos
Nucleosídeos/síntese química , Trítio , Modelos Moleculares , Estrutura Molecular , Nitroimidazóis/síntese química , Nitroimidazóis/química , Estereoisomerismo , Relação Estrutura-Atividade
17.
Bioorg Med Chem Lett ; 18(20): 5563-6, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18815032

RESUMO

Synthesis of 4-amino-4,6-androstadiene-3,17-dione 7, an analog of formestane used in breast cancer therapy as an aromatase inhibitor, from 4-acetoxy-4-androstene-3,17-dione 2 is described. This is the first report of a 4-amino diene (4,6) system in this series of molecules. The new (7) and reported molecules were screened by the National Cancer Institute (NCI, Bethesda, USA) for in vitro antitumor activity against 60 human cancer cell lines. Molecule 7 showed best activity against breast cancer cell line (MCF-7).


Assuntos
Androstadienos/química , Androstenodiona/análogos & derivados , Antineoplásicos/síntese química , Neoplasias da Mama/tratamento farmacológico , Química Farmacêutica/métodos , Androstenodiona/síntese química , Androstenodiona/química , Androstenodiona/farmacologia , Antineoplásicos/farmacologia , Aromatase/metabolismo , Linhagem Celular Tumoral , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Químicos
18.
Pharmaceutics ; 10(1)2018 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-29470434

RESUMO

The objective of this work is to evaluate the potential effect of cardiac stress exercise on the accumulation of [123I]IAZA, a radiopharmaceutical used to image focal tissue hypoxia, in otherwise normal myocardium in healthy volunteers, and to determine the impact of exercise on [123I]IAZA pharmacokinetics. The underlying goal is to establish a rational basis and a baseline for studies of focal myocardial hypoxia in cardiac patients using [123I]IAZA. Three healthy male volunteers ran the 'Bruce' treadmill protocol, a clinically-accepted protocol designed to expose myocardial ischemia in patients. The 'Bruce' criterion heart rate is 85% of [220-age]. Approximately one minute before reaching this level, [123I]IAZA (5.0 mCi/0.85 mg) was administered as a slow (1-3 min) single intravenous (i.v.) injection via an indwelling venous catheter. The volunteer continued running for an additional 1 min before being transferred to a gamma camera. Serum samples were collected from the arm contralateral to the administration site at pre-determined intervals from 1 min to 45 h post injection and were analyzed by radio HPLC. Pharmacokinetic (PK) parameters were derived for [123I]IAZA and total radioactivity (total[123I]) using compartmental and noncompartmental analyses. Whole-body planar scintigraphic images were acquired from 0.75 to 24 h after dosing. PK data and scintigraphic images were compared to previously published [123I]IAZA data from healthy volunteers rest. Following exercise stress, both [123I]IAZA and total[123I] exhibited bi-exponential decline profiles, with rapid distribution phases [half-lives (t1/2α) of 1.2 and 1.4 min, respectively], followed by slower elimination phases [t1/2ß of 195 and 290 min, respectively]. Total body clearance (CLTB) and the steady state volume of distribution (Vss) were 0.647 L/kg and 185 mL/min, respectively, for [123I]IAZA and 0.785 L/kg and 135 mL/min, respectively, for total[123I]. The t1/2ß, CLTB and Vss values were comparable to those reported previously for rested volunteers. The t1/2α was approximately 4-fold shorter for [123I]IAZA and approximately 3-fold shorter for total[123I] under exercise relative to rested subjects. The heart region was visualized in early whole body scintigraphic images, but later images showed no accumulated radioactivity in this region, and no differences from images reported for rested volunteers were apparent. Minimal uptake of radiotracer in myocardium and skeletal muscle was consistent with uptake in non-stressed myocardium. Whole-body scintigrams for [123I]IAZA in exercise-stressed healthy volunteers were indistinguishable from images of non-exercised volunteers. There was no evidence of hypoxia-dependent binding in exercised but otherwise healthy myocardium, supporting the conclusion that exercise stress at Bruce protocol intensity does not induce measurable myocardial hypoxia. Effects of exercise on PK parameters were minimal; specifically, the t1/2α was shortened, reflecting increased cardiac output associated with exercise. It is concluded that because [123I]IAZA was not metabolically bound in exercise-stressed myocardium, a stress test will not create elevated myocardial background that would mask regions of myocardial perfusion deficiency. [123I]IAZA would therefore be suitable for the detection of viable, hypoxic myocardium in patients undergoing stress-test-based diagnosis.

19.
JAMA Oncol ; 4(11): 1597-1604, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30054622

RESUMO

There is no consensus on optimal follow-up for completely resected gastroenteropancreatic neuroendocrine tumors. Published guidelines for follow-up are complex and emphasize closer surveillance in the first 3 years after resection. Neuroendocrine tumors have a different pattern and timescale of recurrence, and thus require more practical and tailored follow-up. The Commonwealth Neuroendocrine Tumour Collaboration convened an international multidisciplinary expert panel, in collaboration with the North American Neuroendocrine Tumor Society, to create patient-centered follow-up recommendations for completely resected gastroenteropancreatic neuroendocrine tumors. This panel used the RAND/UCLA (University of California, Los Angeles) Appropriateness Method to generate recommendations. A large international survey was conducted outlining current the surveillance practice of neuroendocrine tumor practitioners and shortcomings of the current guidelines. A systematic review of available data to date was supplemented by recurrence data from 2 large patient series. The resultant guidelines suggest follow-up for at least 10 years for fully resected small-bowel and pancreatic neuroendocrine tumors and also identify clinical situations in which no follow-up is required. These recommendations stratify follow-up strategies based on evidence-based prognostic factors that allow for a more individualized patient-centered approach to this complex and heterogeneous malignant neoplasm.


Assuntos
Neoplasias Intestinais/cirurgia , Neoplasias Intestinais/terapia , Tumores Neuroendócrinos/cirurgia , Tumores Neuroendócrinos/terapia , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/terapia , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/terapia , Seguimentos , Humanos , Neoplasias Intestinais/patologia , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Neoplasias Gástricas/patologia
20.
Int J Radiat Oncol Biol Phys ; 68(1): 13-23, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17448867

RESUMO

PURPOSE: To standardize the indications, techniques, multimodality treatment approaches, and dosimetry to be used for yttrium-90 (Y90) microsphere hepatic brachytherapy. METHODS AND MATERIALS: Members of the Radioembolization Brachytherapy Oncology Consortium met as an independent group of experts in interventional radiology, radiation oncology, nuclear medicine, medical oncology, and surgical oncology to identify areas of consensus and controversy and to issue clinical guidelines for Y90 microsphere brachytherapy. RESULTS: A total of 14 recommendations are made with category 2A consensus. Key findings include the following. Sufficient evidence exists to support the safety and effectiveness of Y90 microsphere therapy. A meticulous angiographic technique is required to prevent complications. Resin microsphere prescribed activity is best estimated by the body surface area method. By virtue of their training, certification, and contribution to Y90 microsphere treatment programs, the disciplines of radiation oncology, nuclear medicine, and interventional radiology are all qualified to use Y90 microspheres. The panel strongly advocates the creation of a treatment registry with uniform reporting criteria. Initiation of clinical trials is essential to further define the safety and role of Y90 microspheres in the context of currently available therapies. CONCLUSIONS: Yttrium-90 microsphere therapy is a complex procedure that requires multidisciplinary management for safety and success. Practitioners and cooperative groups are encouraged to use these guidelines to formulate their treatment and dose-reporting policies.


Assuntos
Braquiterapia/métodos , Neoplasias Hepáticas/radioterapia , Microesferas , Radioisótopos de Ítrio/uso terapêutico , Braquiterapia/normas , Embolização Terapêutica/métodos , Física Médica/normas , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Seleção de Pacientes , Dosagem Radioterapêutica
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