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1.
Clin Radiol ; 75(8): 641.e1-641.e8, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32354424

RESUMO

AIM: To evaluate clinical, laboratory, imaging findings, and outcomes of adult patients with bone marrow haemophagocytosis (BMH) who meet the diagnostic criteria for haemophagocytic lymphohistiocytosis (HLH) with those who do not meet the criteria. MATERIALS AND METHODS: A pathology database search was performed from 2009 to 2019 to identify adult patients with BMH. Electronic medical records of 41 patients were reviewed to distinguish those who fulfil the HLH-2004 diagnostic guidelines, which identified 22 patients (11 men; mean age, 53.5 years) who met the criteria (HLH+) and 19 patients (13 men; mean age, 54.7 years) who did not meet the criteria (HLH-). Multi-modality imaging was reviewed to record imaging features. Clinical, laboratory, imaging findings, and outcomes were compared between the two groups using Fisher's exact test and Wilcoxon test. RESULTS: Malignancy (non-Hodgkin's lymphoma) was the major trigger for both groups. 86% of HLH+ and 31% of HLH- patients presented with fever. Compared to the HLH- group, the HLH+ group exhibited higher serum ferritin, triglycerides, and lower fibrinogen levels (p<0.05). Alveolar opacities and hepatosplenomegaly were the most common imaging findings identified in both groups. Median overall survival of HLH+ and HLH- were 123.5 (interquartile range [IQR]: 40.7-681.7 days) and 189 days (IQR: 52-1680 days), respectively. Distribution of imaging features and overall survival did not differ between the groups. CONCLUSION: Malignancy is the major trigger for BMH in both HLH+ and HLH- groups. HLH+ and HLH- groups have similar imaging manifestations or clinical outcomes. Therefore, presence of BMH alone is correlated with high morbidity and mortality.


Assuntos
Medula Óssea/diagnóstico por imagem , Linfo-Histiocitose Hemofagocítica/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Feminino , Humanos , Linfo-Histiocitose Hemofagocítica/epidemiologia , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia , Adulto Jovem
2.
Clin Radiol ; 75(2): 157.e9-157.e19, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31711637

RESUMO

AIM: To compare the diagnostic performance of prostate magnetic resonance imaging (MRI) with an endorectal coil (ERC) to performance without an ERC using either body-array (BAC) or pelvic phased-array coil (PAC) in staging T3 prostate cancer. MATERIALS AND METHODS: An electronic search of the PUBMED and EMBASE databases was performed until 10 October 2018 to identify studies performing a head-to-head comparison of prostate MRI using a 1.5 or 3 T magnet with an ERC and with a BAC/PAC for staging T3 prostate cancer. Pooled sensitivity and specificity of all studies were plotted in a hierarchical summary receiver operating characteristic plot. The diagnostic performance of the two techniques in staging T3 disease was evaluated using bivariate random-effects meta-analysis. RESULTS: Eight studies comparing head-to-head prostate MRI with an ERC and with a BAC/PAC were identified of which six studies compared the diagnostic performance. The pooled sensitivity and specificity of MRI with an ERC for detecting T3a, T3b and T3a+b was 53% and 95%; 52% and 92%; 72% and 65% respectively. For MRI with a BAC/PAC these were 34%, and 95%; 45% and 94%; 70% and 66%. There was no statistical difference between an ERC and a BAC/PAC in terms of sensitivity (p=0.41) and specificity (p=0.63) for T3a. The area under the receiver operating characteristic (AUROC) curve for T3a, T3b and T3a+b was 0.830, 0.901, 0.741 for an ERC and 0.790, 0.645, 0.711 for BAC, respectively. CONCLUSION: There is no significant difference in the diagnostic performance of MRI of prostate with an ERC and with a BAC/PAC in staging T3 prostate cancer.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias da Próstata/diagnóstico , Adulto , Idoso , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética Multiparamétrica/instrumentação , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Estadiamento de Neoplasias/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Reto , Sensibilidade e Especificidade
3.
Clin Radiol ; 74(10): 746-755, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31345555

RESUMO

Imaging plays an active role in the surveillance of gastrointestinal stromal tumours (GISTs). Risk stratification schemes, based on size, mitotic count, and anatomical site of origin of the GIST, help in planning preoperative and postoperative imaging strategies especially in determining the frequency and duration of surveillance; however, there is no clear consensus on the optimal imaging strategies in patients with GISTs who are completely cured by surgery and patients who are at risk of recurrence. In addition, current surveillance protocols depend on the resectability of the primary tumour and presence of metastatic disease. The objective of this article is to provide a comprehensive review of the role of the different imaging methods for surveillance of GISTs, focusing on the guidelines recommended by National Comprehensive Cancer Network and European Society of Medical Oncology - European Network for Rare adult solid Cancers, and to propose practical guidelines for surveillance of GISTs for various risk categories.


Assuntos
Neoplasias Gastrointestinais/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Quimioterapia Adjuvante , Continuidade da Assistência ao Paciente , Meios de Contraste , Diagnóstico por Imagem/métodos , Resistencia a Medicamentos Antineoplásicos , Diagnóstico Precoce , Neoplasias Gastrointestinais/terapia , Tumores do Estroma Gastrointestinal/terapia , Humanos , Mesilato de Imatinib/uso terapêutico , Metástase Neoplásica/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Inibidores de Proteínas Quinases/uso terapêutico , Medição de Risco
4.
Clin Radiol ; 73(2): 158-167, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28958581

RESUMO

AIM: To evaluate the yield of staging bone scintigraphy in patients with treatment-naive prostate cancer. MATERIALS AND METHODS: A computerised search of the MEDLINE and EMBASE databases was performed to find relevant original literature. Studies that investigated the positivity of a staging bone scintigraphy according to prostate-specific antigen (PSA) levels and/or Gleason score in patients with treatment-naive prostate cancer were eligible for inclusion. Meta-analytic pooling was performed using the inverse variance method for calculating weights. RESULTS: Fifty-four eligible studies, which included a total sample size of 20,421 patients, were included. The pooled proportions of the positive bone scintigraphy in patients with PSA ≤10, 10 20 were 3.5% (95% confidence interval [CI]: 2.4-5%), 6.9% (95% CI: 4.5-10.3%), and 41.8% (95% CI: 36.3-47.6%). The pooled proportions of the positive bone scintigraphy examinations in patients with Gleason score ≤6, 7, and ≥8 were 4.1% (95% CI: 2-8%), 10% (95% CI: 6.1-15.8%), and 28.7% (95% CI: 21.8-36.8%). Meta-regression analysis revealed that the Gleason score was a significant factor affecting study heterogeneity in patients with PSA ≤10 (p = 0.04). Pooled proportions of positive bone scintigraphy examinations showed 3.4% in patients with a PSA of ≤10 and 3.3% in patients with 10

Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Neoplasias da Próstata/patologia , Humanos , Masculino , Próstata/diagnóstico por imagem , Cintilografia/métodos
5.
Clin Radiol ; 72(7): 521-533, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28476244

RESUMO

The purpose of this review is to familiarise radiologists with the spectrum of hepatic toxicity seen in the oncology setting, in view of the different systemic therapies used in cancer patients. Drug-induced liver injury can manifest in various forms, and anti-neoplastic agents are associated with different types of hepatotoxicity. Although chemotherapy-induced liver injury can present as hepatitis, steatosis, sinusoidal obstruction syndrome, and chronic parenchymal damages, molecular targeted therapy-associated liver toxicity ranges from mild liver function test elevation to fulminant life-threatening acute liver failure. The recent arrival of immune checkpoint inhibitors in oncology has introduced a new range of immune-related adverse events, with differing mechanisms of liver toxicity and varied imaging presentation of liver injury. High-dose chemotherapy regimens for haematopoietic stem cell transplantation are associated with sinusoidal obstruction syndrome. Management of hepatic toxicity depends on the clinical scenario, the drug in use, and the severity of the findings. In this article, we will (1) present the most common types of oncological drugs associated with hepatic toxicity and associated liver injuries; (2) illustrate imaging findings of hepatic toxicities and the possible differential diagnosis; and (3) provide a guide for management of these conditions.


Assuntos
Antineoplásicos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico por imagem , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Transplante de Células-Tronco Hematopoéticas , Terapia de Alvo Molecular/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Institutos de Câncer , Doença Hepática Induzida por Substâncias e Drogas/terapia , Árvores de Decisões , Humanos , Ipilimumab , Nivolumabe , Centros de Atenção Terciária
6.
Clin Radiol ; 71(3): e143-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26767544

RESUMO

AIM: To investigate the yield of imaging in patients with relapsed prostate cancer (PC) with a low trigger prostate-specific antigen (PSA). MATERIALS AND METHODS: This institutional review board (IRB)-approved, Health Insurance Portability and Accountability Act (HIPAA)-compliant retrospective study included all 133 patients (mean age 68 years; range 45-88; median 69 months since original diagnosis; interquartile range [IQR]: 32-139) with hormone-sensitive PC (HSPC, n=28) or castration-resistant PC (CRPC, n=105) and trigger PSA <4 ng/ml, who underwent same-day bone scintigraphy and computed tomography (CT; total 224 time points) at Dana-Farber Cancer Institute from January to December 2013. Clinical and pathological data were obtained by manual review of the electronic medical records. All the included bone scintigraphs and CT images were reviewed by a fellowship-trained oncoradiologist to record the metastatic pattern and any clinically significant non-metastatic findings. RESULTS: Ninety-four of the 133 (71%) patients had metastatic disease (18/28 [64%] with HSPC, 76/105 [72%] with CRPC). Forty-one of the 133 (31%) patients developed new metastatic disease and 23/133 (17%) developed new clinically significant non-metastatic findings. The incidence of osseous, nodal, and visceral metastases, and clinically significant non-metastatic findings was similar across the HSPC and CRPC groups (p>0.05 for all). Fifty-seven of the 133 (43%) patients had findings seen only at CT, of which 37 had new extra-osseous findings. Only 2/133 (2%) had findings at bone scintigraphy not seen at CT, both in areas not covered on CT. CONCLUSION: Imaging frequently demonstrated new metastatic and non-metastatic findings in patients with a low trigger PSA. CT is valuable in these patients because extra-osseous findings not visible at bone scintigraphy are frequently seen.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Biomarcadores Tumorais/sangue , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/patologia , Cintilografia , Estudos Retrospectivos
7.
Clin Radiol ; 71(10): 1010-1017, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27267746

RESUMO

AIM: To determine the patterns of metastasis and recurrence in thymic epithelial tumours based on longitudinal imaging studies, and to correlate the patterns with World Health Organization (WHO) histological classifications. MATERIALS AND METHODS: Seventy-seven patients with histopathologically confirmed thymomas (n=62) and thymic carcinomas (n=15) who were followed with cross-sectional follow-up imaging after surgery were retrospectively studied. All cross-sectional imaging studies during the disease course were reviewed to identify metastasis or recurrence. The sites of involvement and the time of involvement measured from surgery were recorded. RESULTS: Metastasis or recurrence was noted in 24 (31%) of the 77 patients. Patients with metastasis or recurrence were significantly younger than those without (median age: 46 versus 60, respectively; p=0.0005), and more commonly had thymic carcinomas than thymomas (p=0.002). The most common site of involvement was the pleura (17/24), followed by the lung (9/24), and thoracic nodes (9/24). Abdominopelvic involvement was noted in 12 patients, most frequently in the liver (n=8). Lung metastasis was more common in thymic carcinomas than thymomas (p=0.0005). Time from surgery to the development of metastasis or recurrence was shortest in thymic carcinoma, followed by high-risk thymomas, and was longest in low-risk thymoma (median time in months: 25.1, 68.8, and not reached, respectively; p=0.0015). CONCLUSIONS: The patterns of metastasis and recurrence of thymic epithelial tumours differ significantly across histological subgroups, with thymic carcinomas more commonly having metastasis with shorter length of time after surgery. The knowledge of different patterns of tumour spread may contribute to further understanding of the biological and clinical behaviours of these tumours.


Assuntos
Diagnóstico por Imagem/métodos , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Pleurais/secundário , Neoplasias Torácicas/secundário , Neoplasias do Timo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Neoplasias Pleurais/diagnóstico por imagem , Estudos Retrospectivos , Neoplasias Torácicas/diagnóstico por imagem , Adulto Jovem
8.
Dis Esophagus ; 28(6): 552-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24635682

RESUMO

Malignant esophageal neoplasms other than squamous cell carcinoma and adenocarcinoma are uncommon and include endocrine tumors, lymphoid malignancies, melanoma, malignant stromal tumors, and secondary tumors (metastases). Imaging, though not diagnostic in many cases, helps in selecting the appropriate treatment strategy by determining the anatomic extent of the tumor and locoregional and distant spread. In this article, we provide a comprehensive review of the imaging features of these uncommon esophageal malignancies.


Assuntos
Diagnóstico por Imagem/métodos , Neoplasias Esofágicas/patologia , Feminino , Tumores do Estroma Gastrointestinal/patologia , Humanos , Linfoma/patologia , Masculino , Melanoma/patologia , Mesenquimoma/patologia , Pessoa de Meia-Idade , Tumores Neuroendócrinos/patologia
9.
Clin Radiol ; 69(12): e463-70, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25240565

RESUMO

There is increasing focus on intrahepatic cholangiocarcinoma (IHCC) due to its rising incidence worldwide and relatively poor prognosis, with the revised TNM classification (2009) introducing a separate staging system for IHCC for the first time. In this article, we comprehensively review the current role of the radiologist in the diagnosis and management of patients with IHCC.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/cirurgia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/cirurgia , Diagnóstico por Imagem/métodos , Ductos Biliares/diagnóstico por imagem , Ductos Biliares/patologia , Ductos Biliares/cirurgia , Colangiografia/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos
10.
Clin Radiol ; 69(2): e100-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24290835

RESUMO

AIM: To study the clinical and multidetector computed tomography (MDCT) features of tumour-bowel fistula (TBF). MATERIALS AND METHODS: Fifty-one patients (27 women; mean age 57.4 years, range 30-77years) with TBF presenting to our institution between January 2005 and February 2012 were identified retrospectively from the radiology database. MDCT images before, at, and subsequent to diagnosis of TBF were reviewed by three radiologists in consensus; clinical presentation, management, and outcome were documented from electronic medical records. RESULTS: Of 51 patients, small bowel (n = 22) was the most common site with gastrointestinal stromal tumour (GIST) being the most common sarcoma subtype (n = 10). TBF was treatment-associated (TTBF) in 40 patients [78%; 22 of whom had received molecular targeted therapy (MTT)], and spontaneous (STBF) in 11 patients (22%). Thirty-one patients (61%) were symptomatic at the time of TBF detection. TTBF was more often asymptomatic (19/40 versus 1/11; Fisher's exact test p = 0.03). In the TTBF group, 16 had a partial response, seven had stable disease, and 17 had progressive disease. Treatment was discontinued or changed to an alternative regimen in 27/40 patients, and 13/40 patients continued with the same regimen. TBF persisted in 27/33 patients (82%) who underwent CT follow-up. Thirty-one of the 51 patients were deceased at the time of analysis. Time from diagnosis of TBF to death was shorter with STBF (1.8 months) than with TTBF (6.4 months). CONCLUSION: TBF is often associated with MTT and can be seen with treatment response or progression. TTBF is more frequently asymptomatic. TBF is usually managed conservatively by discontinuing treatment, but often persists on CT follow-up.


Assuntos
Neoplasias Gastrointestinais/terapia , Tumores do Estroma Gastrointestinal/terapia , Fístula Intestinal/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Adulto , Idoso , Meios de Contraste , Feminino , Neoplasias Gastrointestinais/complicações , Neoplasias Gastrointestinais/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/complicações , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Fístula Intestinal/complicações , Intestino Delgado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Serviço Hospitalar de Oncologia , Intensificação de Imagem Radiográfica/métodos , Estudos Retrospectivos
11.
Clin Radiol ; 69(12): 1219-27, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25308238

RESUMO

AIMS: To study the differences in the imaging features of spread from the three cancer cell lines, namely epithelial, sarcomatoid, and lymphoid, resulting in peritoneal carcinomatosis, peritoneal sarcomatosis, and peritoneal lymphomatosis, respectively. MATERIALS AND METHODS: In this institutional review board-approved Health Insurance Portability and Accountability Act (HIPAA)-compliant retrospective study, an electronic radiology database was searched to identify patients with peritoneal tumour spread who underwent CT imaging at Dana-Farber Cancer Institute, a tertiary cancer institution, between January 2011 and December 2012. Out of 1214 patients with possible peritoneal tumour spread on the radiology reports, 122 patients were included with histopathologically confirmed peritoneal disease (50 randomly selected patients with peritoneal carcinomatosis and sarcomatosis each, and all 22 patients with lymphomatosis). Two blinded, fellowship-trained radiologists in consensus reviewed the CT images in random order and recorded the imaging findings of peritoneal tumour spread. The statistical analysis was performed in two steps: the first comparing incidence of various features in each group and the second step was a pairwise analysis between each cohort. RESULTS: Peritoneal carcinomatosis more frequently had ascites, peritoneal thickening, and omental cake (all p ≤ 0.001). Measurable nodules were less common in peritoneal carcinomatosis (p < 0.001), and when present, were ill-defined and had an irregular outline (p ≤ 0.002). Peritoneal sarcomatosis more often had discrete nodules that were well defined and had a smooth outline and less frequently had ascites, peritoneal thickening, omental caking, serosal implants, and lymphadenopathy (all p ≤ 0.005). Peritoneal lymphomatosis frequently involved the omentum and mesentery, and often had associated lymphadenopathy and splenomegaly (all p ≤ 0.002). CONCLUSION: Peritoneal carcinomatosis, sarcomatosis, and lymphomatosis have distinctive patterns on imaging, which can help the radiologists to differentiate between them.


Assuntos
Carcinoma/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Neoplasias Peritoneais/diagnóstico por imagem , Sarcoma/diagnóstico por imagem , Centros de Atenção Terciária , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Peritônio/diagnóstico por imagem , Estudos Retrospectivos
12.
Clin Radiol ; 69(2): 137-44, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24161459

RESUMO

AIM: To describe the multidetector computed tomography (MDCT) features of primary, locally recurrent, and metastatic duodenal gastrointestinal stromal tumours (GISTs). MATERIALS AND METHODS: In this institutional review board-approved, Health Insurance Portability and Accountability Act of 1996 (HIPAA)-compliant, retrospective study, 25 patients [13 men, 12 women; mean age 56 years (34-74 years)] with histopathologically confirmed duodenal GISTs seen at Dana Farber Cancer Institute and Brigham and Women's Hospital from December 1999 to October 2009 were identified. The MDCT of primary tumours in six patients and follow-up imaging in all the 25 patients was reviewed by two radiologists in consensus. Electronic medical records were reviewed to document the clinical characteristics and management. RESULTS: The mean size of the primary tumour was 3.7 cm (range 2.5-5.6 cm). Three of six primary tumours were in the second and third portions of the duodenum, one in the third portion, one in the third and fourth portions, and one in the fourth portion. Three of six of the tumours were exophytic, two were both exophytic and intraluminal, and one was intramural. The tumours were well-circumscribed, round or oval masses, with few lobulations, and were either homogeneously hyper-enhancing or heterogeneously isodense at MDCT. None of the tumours had necrosis, haemorrhage, calcification, or loco regional lymphadenopathy on imaging. Sixteen of 25 (64%) patients developed metastatic disease, the most common sites being liver (14/16; 87.5%) and peritoneum (5/16; 31%). CONCLUSION: Duodenal GISTs are well-circumscribed, round or oval masses, and occur in the second through fourth portions of the duodenum, without lymphadenopathy or duodenal obstruction. Duodenal GISTS metastasize frequently to the liver and peritoneum.


Assuntos
Neoplasias Duodenais/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Recidiva Local de Neoplasia/diagnóstico por imagem , Adulto , Idoso , Meios de Contraste , Neoplasias Duodenais/patologia , Neoplasias Duodenais/secundário , Duodeno/diagnóstico por imagem , Feminino , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/secundário , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Intensificação de Imagem Radiográfica/métodos , Estudos Retrospectivos
13.
Clin Radiol ; 68(8): e429-37, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23622797

RESUMO

Gastrointestinal stromal tumour resistance to treatment with imatinib occurs due to pre-existing or acquired mutations. Computed tomography and positron-emission tomography play an essential role in prompt recognition of resistance to treatment. Primary resistance to treatment, which is encountered in the first 6 months of treatment, is associated with specific mutations. Imaging of these tumours shows no anatomical or metabolic response to treatment. Secondary resistance to treatment, which develops after an initial response, is associated with a variety of mutations acquired after the start of treatment. Imaging findings of secondary resistance are of disease progression.


Assuntos
Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Piperazinas/uso terapêutico , Tomografia por Emissão de Pósitrons , Pirimidinas/uso terapêutico , Tomografia Computadorizada por Raios X , Meios de Contraste , Progressão da Doença , Fluordesoxiglucose F18 , Tumores do Estroma Gastrointestinal/genética , Humanos , Mesilato de Imatinib , Mutação , Compostos Radiofarmacêuticos
14.
Sci Rep ; 13(1): 16087, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752170

RESUMO

We present experimental results of the trace argon impurity puffing in the ohmic plasmas of Aditya-U tokamak performed to study the argon transport behaviour. Argon line emissions in visible and Vacuum Ultra Violet (VUV) spectral ranges arising from the plasma edge and core respectively are measured simultaneously. During the experiments, space resolved brightness profile of Ar1+ line emissions at 472.69 nm (3p44s 2P3/2-3p44p 2D3/2), 473.59 nm (3p44s 4P5/2-3p44p 4P3/2), 476.49 nm (3p44s 2P1/2-3p44p 2P3/2), 480.60 nm (3p44s 4P5/2-3p44p 4P5/2) are recorded using a high resolution visible spectrometer. Also, a VUV spectrometer has been used to simultaneously observe Ar13+ line emission at 18.79 nm (2s22p 2P3/2-2s2p2 2P3/2) and Ar14+ line emission at 22.11 nm (2s2 1S0-2s2p 1P1). The diffusivity and convective velocity of Ar are obtained by comparing the measured radial emissivity profile of Ar1+ emission and the line intensity ratio of Ar13+ and Ar14+ ions, with those simulated using the impurity transport code, STRAHL. Argon diffusivities ~ 12 m2/s and ~ 0.3 m2/s have been observed in the edge (ρ > 0.85) and core region of the Aditya-U, respectively. The diffusivity values both in the edge and core region are found to be higher than the neo-classical values suggesting that the argon impurity transport is mainly anomalous in the Aditya-U tokamak. Also, an inward pinch of ~ 10 m/s mainly driven by Ware pinch is required to match the measured and simulated data. The measured peaked profile of Ar density suggests impurity accumulation in these discharges.

15.
Rev Sci Instrum ; 93(11): 113552, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461425

RESUMO

Spectroscopy in vacuum ultraviolet (VUV) and visible ranges plays an important role in the investigation and diagnosis of tokamak plasmas. However, under harsh environmental conditions of fusion grade devices, such as ITER, VUV-visible systems encounter many issues due to the degradation of optical components used in such systems. Here, near-infrared (NIR) spectroscopy has become an effective tool in understanding the edge plasma dynamics. Considering its importance, a NIR spectroscopic diagnostic has been developed and installed on the ADITYA-U tokamak. The system consists of a 0.5 m spectrometer having three gratings with different groove densities, and it is coupled with a linear InGaAs photodiode array. Radiation from the ADITYA-U edge plasma has been collected using a collimating lens and optical fiber combination and transported to the spectrometer. The spectrum in the NIR range from the ADITYA-U plasma has been recorded using this system, in which Paß and Paγ along with many spectral lines from neutral and singly ionized impurities have been observed. The influxes of H and C have been estimated from measurements. The H influx value is found to be 2.8 × 1016 and 1.9 × 1016 particles cm-2 s-1 from neutral hydrogen lines Hα and Paß, respectively, and the C influx value is found to be 3.5 × 1015 and 2.9 × 1015 particles cm-2 s-1 from the neutral carbon and singly ionized carbon, respectively. A good agreement is seen between these results and the results obtained by using a routine photomultiplier tube based diagnostic.

16.
Rev Sci Instrum ; 92(6): 063517, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243548

RESUMO

A high-resolution spectroscopic diagnostic for the measurement of spatial profiles of impurity ion toroidal rotation velocities on the ADITYA-U tokamak has been upgraded to cover the complete plasma minor radius. Earlier, the coverage of diagnostics toward the plasma edge was restricted due to the placement of collection optics on the tangential port outside the vacuum vessel. The coverage of the full plasma minor radius, from 0 to 24 cm, has been achieved using the newly designed and developed collection optics that have seven lines of sight to view the tokamak plasma mounted inside a customized re-entrant view port which is installed in the shadow of the limiter inside the vacuum vessel. The upgraded diagnostic also includes a faster charged coupled device detector with a smaller pixel size for the detection of a small wavelength shift. The complete spatial profile has been measured using the Doppler shifted passive change exchange spectral line at 529.0 nm from the C5+ ion. In this article, we present the collection optics' design, installation, calibration, and results obtained using the upgraded diagnostic.

17.
Rev Sci Instrum ; 92(5): 053548, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243287

RESUMO

The spectroscopic studies of medium and high Z impurities have been the subject of interest in fusion research due to their role in mitigating plasma disruption and reducing heat load on the plasma facing components. Line emissions from these impurities provide the rotation velocity and ion temperature measurements along with the understanding of the overall impurity behavior in plasma. In the Aditya-U tokamak, the spatially resolved Ar II line emissions have been observed using a high resolution multi-track spectroscopic diagnostic consisting of a 1 m Czerny-Turner spectrometer coupled with a charge coupled device (CCD) detector using seven lines of sight viewing plasma tangentially along the toroidal direction. The spatially resolved Ar II lines at 458.96 nm have been observed. The singly ionized Ar emission peaks at the radial location of ρ = 0.8 of the plasma having a minor radius of 25 cm. Moreover, a 0.5 m UV-visible spectrometer coupled with a CCD detector and having a line of sight passing through the plasma midplane from the radial port was used to record visible Ar survey spectra within the 670-810 nm wavelength range, and all these lines have been identified for further analysis.

18.
AJNR Am J Neuroradiol ; 41(5): 738-750, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32217548

RESUMO

Treatment options for patients who develop brain metastases secondary to non-small-cell lung cancer have rapidly expanded in recent years. As a key adjunct to surgical and radiation therapy options, systemic therapies are now a critical component of the oncologic management of metastatic CNS disease in many patients with non-small-cell lung cancer. The aim of this review article was to provide a guide for radiologists, outlining the role of systemic therapies in metastatic non-small-cell lung cancer, with a focus on tyrosine kinase inhibitors. The critical role of the blood-brain barrier in the development of systemic therapies will be described. The final sections of this review will provide an overview of current imaging-based guidelines for therapy response. The utility of the Response Assessment in Neuro-Oncology criteria will be discussed, with a focus on how to use the response criteria in the assessment of patients treated with systemic and traditional therapies.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/secundário , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Radiologistas
19.
Eur J Radiol ; 109: 114-123, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30527292

RESUMO

OBJECTIVES: The well-known boost of iodine associated-attenuation in low-keV virtual monoenergetic images (VMI_low) is frequently used to improve visualization of lesions and structures taking up contrast media. This study aimed to evaluate this concept in reverse. Hence to investigate if increased attenuation within the liver allows for improved visualization of little or not-enhancing lesions. METHODS: A 3D-printed phantom mimicking the shape of a human liver exhibiting a lesion in its center was designed and printed. Both, parenchyma- and lesion-mimic were filled with different solutions exhibiting 80/100/120HU and 0/15/40/60HU, respectively. Further, a total of 74 contrast-enhanced studies performed on a spectral detector CT scanner (SDCT) were included in this retrospective study. Patients had MRI or follow-up proven cysts and/or hypodense metastases. VMI of 40-200 keV as well as conventional images (CI) were reconstructed. ROI were placed in lesion and parenchyma(-mimics) on CI and transferred to VMI. Signal- and contrast-to-noise ratio were calculated (S-/CNR). Further, two radiologists independently evaluated image quality. Data was statistically assessed using ANOVA or Wilcoxon-test. RESULTS: In phantoms, S/CNR was significantly higher in VMI_low. The cyst-mimic in highly attenuating parenchyma-mimic on CI yielded a CNR of 6.4 ± 0.8; using VMI_40 keV, mildly hypodense lesion-mimic in poorly attenuating parenchyma-mimic exhibited a similar CNR (5.8 ± 0.9; p ≤ 0.05). The same tendency was observed in patients (cyst in CI/metastasis in VMI_40 keV: 4.4 ± 1.2/3.9 ± 1.8; p ≤ 0.05). Qualitative analysis indicated a benefit of VMI_40 keV (p ≤ 0.05). CONCLUSIONS: VMI_low from SDCT allow for an improved visualization of hypodense focal liver lesions exploiting the concept of contrast blooming in reverse.


Assuntos
Neoplasias Hepáticas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistos/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Doses de Radiação , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Razão Sinal-Ruído , Tomógrafos Computadorizados , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos
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