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1.
Nature ; 595(7866): 223-226, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234332

RESUMO

Neutron-star mergers were recently confirmed as sites of rapid-neutron-capture (r-process) nucleosynthesis1-3. However, in Galactic chemical evolution models, neutron-star mergers alone cannot reproduce the observed element abundance patterns of extremely metal-poor stars, which indicates the existence of other sites of r-process nucleosynthesis4-6. These sites may be investigated by studying the element abundance patterns of chemically primitive stars in the halo of the Milky Way, because these objects retain the nucleosynthetic signatures of the earliest generation of stars7-13. Here we report the element abundance pattern of the extremely metal-poor star SMSS J200322.54-114203.3. We observe a large enhancement in r-process elements, with very low overall metallicity. The element abundance pattern is well matched by the yields of a single 25-solar-mass magnetorotational hypernova. Such a hypernova could produce not only the r-process elements, but also light elements during stellar evolution, and iron-peak elements during explosive nuclear burning. Hypernovae are often associated with long-duration γ-ray bursts in the nearby Universe8. This connection indicates that similar explosions of fast-spinning strongly magnetized stars occurred during the earliest epochs of star formation in our Galaxy.

2.
Eur J Nucl Med Mol Imaging ; 51(2): 590-603, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37747578

RESUMO

AIMS: To report long-term outcomes of relapsed prostate cancer (PC) patients treated in a prospective single-arm study with extended-nodal radiotherapy (ENRT) and [11C]-choline positron emission tomography (PET)/computed tomography (CT)-guided simultaneous integrated boost (SIB) to positive lymph nodes (LNs). METHODS: From 12/2009 to 04/2015, 60 PC patients with biochemical relapse and positive LNs only were treated in this study. ENRT at a median total dose (TD) = 51.8 Gy/28 fr and PET/CT-guided SIB to positive LNs at a median TD = 65.5 Gy was prescribed. Median PSA at relapse was 2.3 (interquartile range, IQR:1.3-4.0) ng/ml. Median number of positive LNs: 2 (range: 1-18). Androgen deprivation therapy (ADT) was prescribed for 48 patients for a median of 30.7 (IQR: 18.5-43.1) months. RESULTS: Median follow-up from the end of salvage treatment was 121.8 (IQR: 116.1, 130.9) months; 3-, 5-, and 10-year BRFS were 45.0%, 36.0%, and 24.0%, respectively; DMFS: 67.9%, 57.2%, and 45.2%; CRFS: 62.9%, 53.9%, and 42.0%; and OS: 88.2%, 76.3%, and 47.9%, respectively. Castration resistance (p < 0.0001) and ≥ 6 positive LN (p = 0.0024) significantly influenced OS at multivariate analysis. Castration resistance (p < 0.0001 for both) influenced DMFS and CRFS in multivariate analysis. CONCLUSIONS: In PC relapsed patients treated with ENRT and [11C]-choline-PET/CT-guided SIB for positive LNs, with 10-year follow-up, a median Kaplan-Meier estimate CRFS of 67 months and OS of 110 months were obtained. These highly favorable results should be confirmed in a prospective, randomized trial.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Humanos , Masculino , Antagonistas de Androgênios/uso terapêutico , Radioisótopos de Carbono , Colina , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/radioterapia , Recidiva Local de Neoplasia/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/patologia , Ensaios Clínicos como Assunto
4.
Ann Oncol ; 30(11): 1697-1727, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31740927

RESUMO

BACKGROUND: Although guidelines exist for advanced and variant bladder cancer management, evidence is limited/conflicting in some areas and the optimal approach remains controversial. OBJECTIVE: To bring together a large multidisciplinary group of experts to develop consensus statements on controversial topics in bladder cancer management. DESIGN: A steering committee compiled proposed statements regarding advanced and variant bladder cancer management which were assessed by 113 experts in a Delphi survey. Statements not reaching consensus were reviewed; those prioritised were revised by a panel of 45 experts before voting during a consensus conference. SETTING: Online Delphi survey and consensus conference. PARTICIPANTS: The European Association of Urology (EAU), the European Society for Medical Oncology (ESMO), experts in bladder cancer management. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Statements were ranked by experts according to their level of agreement: 1-3 (disagree), 4-6 (equivocal), 7-9 (agree). A priori (level 1) consensus was defined as ≥70% agreement and ≤15% disagreement, or vice versa. In the Delphi survey, a second analysis was restricted to stakeholder group(s) considered to have adequate expertise relating to each statement (to achieve level 2 consensus). RESULTS AND LIMITATIONS: Overall, 116 statements were included in the Delphi survey. Of these, 33 (28%) statements achieved level 1 consensus and 49 (42%) statements achieved level 1 or 2 consensus. At the consensus conference, 22 of 27 (81%) statements achieved consensus. These consensus statements provide further guidance across a broad range of topics, including the management of variant histologies, the role/limitations of prognostic biomarkers in clinical decision making, bladder preservation strategies, modern radiotherapy techniques, the management of oligometastatic disease and the evolving role of checkpoint inhibitor therapy in metastatic disease. CONCLUSIONS: These consensus statements provide further guidance on controversial topics in advanced and variant bladder cancer management until a time where further evidence is available to guide our approach.


Assuntos
Consenso , Oncologia/normas , Guias de Prática Clínica como Assunto , Neoplasias da Bexiga Urinária/terapia , Urologia/normas , Técnica Delphi , Europa (Continente) , Humanos , Cooperação Internacional , Oncologia/métodos , Estadiamento de Neoplasias , Sociedades Médicas/normas , Participação dos Interessados , Inquéritos e Questionários , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia , Urologia/métodos
5.
Eur J Nucl Med Mol Imaging ; 45(5): 751-758, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29192364

RESUMO

AIM: During our daily clinical practice using 11C-Choline PET/CT for restaging patients affected by relapsing prostate cancer (rPCa) we noticed an unusual but significant occurrence of hypodense hepatic lesions with a different tracer uptake. Thus, we decided to evaluate the possible correlation between rPCa and these lesions as possible hepatic metastases. MATERIALS AND METHODS: We retrospectively enrolled 542 patients diagnosed with rPCa in biochemical relapse after a radical treatment (surgery and/or radiotherapy). Among these, patients with a second tumor or other benign hepatic diseases were excluded. All patients underwent 11C-Choline PET/CT during the standard restaging workup of their disease. We analyzed CT images to evaluate the presence of hypodense lesions and PET images to identify the relative tracer uptake. In accordance to the subsequent oncological history, five clinical scenarios were recognized [Table 1]: normal low dose CT (ldCT) and normal tracer distribution (Group A); evidence of previously unknown hepatic round hypodense areas at ldCT with normal rim uptake (Group B); evidence of previously known hepatic round hypodense areas at ldCT stable over time and with normal rim uptake (Group C); evidence of previously known hepatic round hypodense areas at ldCT, in a previous PET/CT scan, with or without rim uptake and significantly changing over time in terms of size and/or uptake (Group D); evidence of hepatic round hypodense areas at ldCT with or without rim uptake confirmed as prostate liver metastases by histopathology, triple phase ceCT, ce-ultra sound (CEUS) and clinical/biochemical evaluation (Group E). We evaluated the correlation with PSA level at time of scan, rim SUVmax and association with local relapse or non-hepatic metastases (lymph nodes, bone, other parenchyma). RESULTS: Five hundred and forty-two consecutive patients were retrospectively enrolled. In 140 of the 542 patients more than one 11C-choline PET/CT had been performed. A total of 742 11C-Choline PET/CT scans were analyzed. Of the 542 patients enrolled, 456 (84.1%) had a normal appearance of the liver both at ldCT and PET (Group A). 19/542 (3,5%) belonged to Group B, 13/542 (2.4%) to Group C, 37/542 (6.8%) to Group D and 18/542 (3.3%) to Group E. Mean SUVmax of the rim was: 4.5 for Group B; 4.2 for Group C; 4.8 for Group D; 5.9 for Group E. Mean PSA level was 5.27 for Group A, 7.9 for Group B, 10.04 for Group C, 10.01 for Group D, 9.36 for Group E. Presence of positive findings at 11C-Choline PET/CT in any further anatomical area (local relapse, lymph node, bone, other extra hepatic sites) correlated with an higher PSA (p = 0.0285). In both the univariate and multivariate binary logistic regression analyses. PSA, SUVmax of the rim, local relapse, positive nodes were not associated to liver mets (Groups D-E) (p > 0.05). On the contrary, a significant correlation was found between the presence of liver metG (group D-E) and bone lesions (p= 0.00193). CONCLUSION: Our results indicate that liver metastases in relapsing prostate cancer may occur frequently. The real incidence evaluation needs more investigations. In this case and despite technical limitations, Choline PET/CT shows alterations of tracer distribution within the liver that could eventually be mistaken for simple cysts but can be suspected when associated to high trigger PSA, concomitant bone lesions or modification over time. In this clinical setting an accurate analysis of liver tracer distribution (increased or decreased uptake) by the nuclear medicine physician is, therefore, mandatory.


Assuntos
Neoplasias Hepáticas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Radioisótopos de Carbono , Colina , Humanos , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons , Antígeno Prostático Específico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
10.
Radiother Oncol ; 194: 110160, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38369025

RESUMO

PURPOSE: The early regression index (ERI) predicts treatment response in rectal cancer patients. Aim of current study was to prospectively assess tumor response to neoadjuvant chemo-radiotherapy (nCRT) of locally advanced esophageal cancer using ERI, based on MRI. MATERIAL AND METHODS: From January 2020 to May 2023, 30 patients with esophageal cancer were enrolled in a prospective study (ESCAPE). PET-MRI was performed: i) before nCRT (tpre); ii) at mid-radiotherapy, tmid; iii) after nCRT, 2-6 weeks before surgery (tpost); nCRT delivered 41.4 Gy/23fr with concurrent carboplatin and paclitaxel. For patients that skipped surgery, complete clinical response (cCR) was assessed if patients showed no local relapse after 18 months; patients with pathological complete response (pCR) or with cCR were considered as complete responders (pCR + cCR). GTV volumes were delineated by two observers (Vpre, Vmid, Vpost) on T2w MRI: ERI and other volume regression parameters at tmid and tpost were tested as predictors of pCR + cCR. RESULTS: Complete data of 25 patients were available at the time of the analysis: 3/25 with complete response at imaging refused surgery and 2/3 were cCR; in total, 10/25 patients showed pCR + cCR (pCR = 8/22). Both ERImid and ERIpost classified pCR + cCR patients, with ERImid showing better performance (AUC:0.78, p = 0.014): A two-variable logistic model combining ERImid and Vpre improved performances (AUC:0.93, p < 0.0001). Inter-observer variability in contouring GTV did not affect the results. CONCLUSIONS: Despite the limited numbers, interim analysis of ESCAPE study suggests ERI as a potential predictor of complete response after nCRT for esophageal cancer. Further validation on larger populations is warranted.


Assuntos
Neoplasias Esofágicas , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Humanos , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Idoso , Quimiorradioterapia , Paclitaxel/administração & dosagem , Carboplatina/administração & dosagem , Resultado do Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Adulto
12.
Neurol Sci ; 34(10): 1871-3, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23703399

RESUMO

Acute basilar artery occlusion has a poor prognosis and best treatment has not been assessed yet; as for intra-arterial treatment, no "gold standard" exists. We evaluated a series of ten patients treated with intra-arterial combination of recombinant tissue plasminogen activator (rtPA) and abciximab. Partial/complete recanalisation was achieved in all patients and good outcome (1 month Modified Rankin Scale 0-2) in eight cases, while one patient had symptomatic intracranial haemorrhage and died. Such outcome appears significantly better if compared with the results of Basilar Artery International Cooperation Study, suggesting that intra-arterial administration of rtPA and abciximab may be a promising option in patients with acute basilar artery occlusion undergoing endovascular treatment.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Fibrinolíticos/administração & dosagem , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Ativador de Plasminogênio Tecidual/administração & dosagem , Insuficiência Vertebrobasilar/tratamento farmacológico , Abciximab , Adulto , Idoso , Feminino , Seguimentos , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2155-2158, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891715

RESUMO

The prediction at baseline of patients at high risk for therapy failure or recurrence would significantly impact on Hodgkin Lymphoma patients treatment, informing clinical practice. Current literature is extensively searching insights in radiomics, a promising framework for high-throughput imaging feature extraction, to derive biomarkers and quantitative prognostic factors from images. However, existing studies are limited by intrinsic radiomic limitations, high dimensionality among others. We propose an exhaustive patient representation and a recurrence-specific multi-view supervised clustering algorithm for estimating patient-to-patient similarity graph and learning recurrence probability. We stratified patients in two risk classes and characterize each group in terms of clinical variables.


Assuntos
Doença de Hodgkin , Algoritmos , Análise por Conglomerados , Doença de Hodgkin/diagnóstico por imagem , Humanos , Fenótipo , Estudos Retrospectivos
15.
Clin Transl Oncol ; 23(1): 172-178, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32447644

RESUMO

PURPOSE: To compare the diagnostic performance of 68Ga-PSMA PET/TC with PRI-MUS (prostate risk identification using micro-ultrasound) in the primary diagnosis of prostate cancer (PCa). METHODS: From September till December 2018, we prospectively enrolled 25 candidates to 68Ga-PSMA PET/TRUS (transrectal ultrasound) fusion biopsy and compared them with PRI-MUS. This included patients with persistently elevated PSA and/or PHI (prostate health index) suspicious for PCa, negative digital rectal examination, with either negative or contraindication to mpMRI, and at least one negative biopsy. The diagnostic performance of the two modalities was calculated based on pathology results. RESULTS: Overall, 20 patients were addressed to 68Ga-PSMA PET/TRUS fusion biopsy. Mean SUVmax and SUVratio for PCa lesions resulted significantly higher than in benign lesions (p = 0.041 and 0.011, respectively). Using optimal cut-off points, 68Ga-PSMA PET/CT demonstrated an overall accuracy of 83% for SUVmax ≥ 5.4 and 94% for SUVratio ≥ 2.2 in the detection of clinically significant PCa (GS ≥ 7). On counterpart, PRI-MUS results were: score 3 in nine patients (45%), score 4 in ten patients (50%), and one patient with score 5. PRI-MUS score 4 and 5 demonstrated an overall accuracy of 61% in detecting clinically significant PCa. CONCLUSION: In this highly-selected patient population, in comparison to PRI-MUS, 68Ga-PSMA PET/CT shows a higher diagnostic performance.


Assuntos
Isótopos de Gálio , Radioisótopos de Gálio , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/diagnóstico por imagem , Compostos Radiofarmacêuticos , Ultrassonografia/métodos , Idoso , Idoso de 80 Anos ou mais , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia
16.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32278786

RESUMO

BACKGROUND: Recently, evidence has accumulated that demonstrates the potential for future applications of radiomics in many clinical settings, including thoracic oncology. Methodological reasons for the immaturity of image mining (radiomics and artificial intelligence-based) studies have been identified. However, data on the influence of the composition of the research team on the quality of investigations in radiomics are lacking. AIM: This review aims to evaluate the interdisciplinarity within studies on radiomics in thoracic oncology in order to assess its influence on the quality of research (QUADAS-2 score) in the image mining field. METHODS: We considered for inclusion radiomics investigations with objectives relating to clinical practice in thoracic oncology. Subsequently, we interviewed the corresponding authors. The field of expertise and/or educational degree was then used to assess interdisciplinarity. Subsequently, all studies were evaluated applying the QUADAS-2 score and assigned to a research phase from 0 to IV. RESULTS: Overall, 27 studies were included. The study quality according to the QUADAS-2 score was low (score ≤5) in 8, moderate (=6) in 12, and high (≥7) in 7 papers. An interdisciplinary team (at least 3 different expertise categories) was involved in half of the papers without any type of validation and in all papers with independent validation. Clinicians were not involved in phase 0 studies while they contributed to all papers classified as phase I and to 4/5 papers classified as phase II with independent validation. CONCLUSIONS: The composition of the research team influences the quality of investigations in radiomics. Also, growth in interdisciplinarity appears to reflect research development from the early phase to a more mature, clinically oriented stage of investigation.


Assuntos
Pesquisa Biomédica , Comunicação Interdisciplinar , Oncologia/métodos , Radiologia/métodos , Neoplasias Torácicas , Humanos
18.
Ann Surg Oncol ; 16(11): 3190-210, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19795174

RESUMO

Involvement of the cervical lymph nodes is the most important prognostic factor for patients with oral/oropharyngeal squamous cell carcinoma (OSCC), and the decision of whether to electively treat patients with clinically negative necks remains a controversial topic. Sentinel node biopsy (SNB) provides a minimally invasive method for determining the disease status of the cervical node basin, without the need for a formal neck dissection. This technique potentially improves the accuracy of histologic nodal staging and avoids overtreating three-quarters of this patient population, minimizing associated morbidity. The technique has been validated for patients with OSCC, and larger-scale studies are in progress to determine its exact role in the management of this patient population. This document is designed to outline the current best practice guidelines for the provision of SNB in patients with early-stage OSCC, and to provide a framework for the currently evolving recommendations for its use. Preparation of this guideline was carried out by a multidisciplinary surgical/nuclear medicine/pathology expert panel under the joint auspices of the European Association of Nuclear Medicine (EANM) Oncology Committee and the Sentinel European Node Trial (SENT) Committee.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Orofaríngeas/diagnóstico por imagem , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/cirurgia , Humanos , Linfonodos/patologia , Linfonodos/cirurgia , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/cirurgia , Prognóstico , Cintilografia , Biópsia de Linfonodo Sentinela
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